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• Windows Azure Evolution &ndash; Welcome to VS2012

  - by Shaun

  When the Microsoft released the first preview version of Windows 8 and Visual Studio, many people in the community were asking if the windows azure tool is available to it. The answer was “NO”. Microsoft promised that the windows azure tool will only support the Visual Studio 2010 but when the 2012 was final released, windows azure tool should be work. But now alone with the new windows azure platform was published we got the latest Windows Azure SDK 1.7, which is compatible to the Visual Studio 2012 RC.   You can retrieve the latest version of the Windows Azure SDK through Web Platform Installer, which I think it’s the easiest and simplest way to download and install, since besides the SDK itself it also needs some other components. To download the latest windows azure SDK from Web Platform Installer, just go to the windows azure website and clicked the Develop, .NET and click the blue “install” button. Then you need to select which version of Visual Studio you want to use, Visual Studio 2010 or Visual Studio 2012 RC. After selected the current version you will download an EXE file. This file will lead you to install the Web Platform Installer 4.0 (if you haven’t installed) and the latest windows azure SDK. You can see the version name is June 2012, 1.7. Finally the WebPI will detect the dependent components you need to download and begin to install. But if you want to challenge yourself you can download the components and install them manually. The standalone installations are listed in this page with the instruction on how to install them with necessary pre-requirements.   Once you finished the installation you can open the Visual Studio 2012 RC and as usual, it need to be run as administrator. If you clicked the New Project link from the start page, navigated to Cloud category you will find that there no project template available. Is there anything wrong? So, if you changed the target framework from the default .NET 4.5 to .NET 4 you will see the azure project template. This is because, currently the windows azure instance does not support .NET 4.5. After clicked OK you will see the role creation window, which is similar as what you have seen before. But there are some new role templates in this SDK. Firstly you will have ASP.NET MVC 4 web role available, which means you can create ASP.NET MVC 4 applications for internet, intranet, mobile and WebAPI on the cloud. Then there are two new worker role templates, “Cache Worker Role” and “Worker Role with Service Bus Queue”. “Worker Role with Service Bus Queue” is a worker role which had added necessary references to access the Windows Azure Service Bus Queue. It also have some basic sample code in the worker role class which could read messages from the queue when started. The “Cache Worker Role” is a worker role which has the in-memory distributed cache feature enabled by default. This feature is different than the Windows Azure Caching. It allows the role instance to use its memory as a in-memory distributed cache clusters. By using this feature you can have one or more worker roles as some dedicate cache clusters. Alternatively, you can make part of your web role and worker role’s memory as the cache clusters as well. Let’s just create an ASP.NET MVC 4 Web Role, and click F5 to run it under the local emulator. If you have been working with azure for a while you should know that I need to setup the local storage emulator before running locally if it’s a fresh azure SDK installation. But in this version when we started our azure project the Visual Studio will check if the storage emulator had been initialized. If not, it will run the initializer automatically. And as you can see, in this version the storage emulator relies on the SQL Server 2012 Local DB feature. It will create the emulator database and tables in the default local database. You can set the storage emulator to use a standard SQL Server default instance by using the command “dsinit /instance:.”. The “dsinit” tool now is located at %PROGRAM FILES%\Microsoft SDKs\Windows Azure\Emulator\devstore After the Visual Studio complied and deployed the package our website should be shown in the browser. This is the MVC 4 Web Role home page on my Windows 8 machine in IE10. Another thing you might notice is that, in this version the compute emulator utilizes IIS Express to host the web roles instead of the full IIS. You can add breakpoint in the code and debug, and you can use the local storage emulator to test your code for accessing the storage service. All of them are same as what your are doing now on SDK 1.6. You can switch to use IIS to run your web role in local emulator. Just open the windows azure porject property windows, in the Web page select “Use IIS Web Server”. For more information about this please have a look on Nuno’s blog post. In the role property page in Visual Studio there’s no massive changes. You can configure your role settings such as the endpoints, certificates and local storage, etc.. One thing was added is the Caching tab. Here you can specify enable the caching feature or not, and how much memory you want to use as the cache cluster. I will introduce more details about it in the future posts. The publish and package feature are also no change. You can publish your project to azure directly through Visual Studio 2012, while you can create the package and upload manually. Below is the SDK version of my deployment which is 1.7.30602.1703 in the developer portal.   Summary In this post I introduced about the new Windows Azure SDK 1.7 especially on how it works on the latest Visual Studio 2012 RC. There’s no significant changes in the visual studio tool in this version but some small enhancement such as ASP.NET MVC 4, Cache Worker Role, using SQL 2012 Local DB and IIS Express, etc..   Hope this helps, Shaun All documents and related graphics, codes are provided "AS IS" without warranty of any kind. Copyright © Shaun Ziyan Xu. This work is licensed under the Creative Commons License.

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• Community Conversation

  - by ultan o'broin

  Applications User Experience members (Erika Webb, Laurie Pattison, and I) attended the User Assistance Europe Conference in Stockholm, Sweden. We were impressed with the thought leadership and practical application of ideas in Anne Gentle's keynote address "Social Web Strategies for Documentation". After the conference, we spoke with Anne to explore the ideas further. Applications User Experience Senior Director Laurie Pattison (left) with Anne Gentle at the User Assistance Europe Conference In Anne's book called Conversation and Community: The Social Web for Documentation, she explains how user assistance is undergoing a seismic shift. The direction is away from the old print manuals and online help concept towards a web-based, user community-driven solution using social media tools. User experience professionals now have a vast range of such tools to start and nurture this "conversation": blogs, wikis, forums, social networking sites, microblogging systems, image and video sharing sites, virtual worlds, podcasts, instant messaging, mashups, and so on. That user communities are a rich source of user assistance is not a surprise, but the extent of available assistance is. For example, we know from the Consortium for Service Innovation that there has been an 'explosion' of user-generated content on the web. User-initiated community conversations provide as much as 30 times the number of official help desk solutions for consortium members! The growing reliance on user community solutions is clearly a user experience issue. Anne says that user assistance as conversation "means getting closer to users and helping them perform well. User-centered design has been touted as one of the most important ideas developed in the last 20 years of workplace writing. Now writers can take the idea of user-centered design a step further by starting conversations with users and enabling user assistance in interactions." Some of Anne's favorite examples of this paradigm shift from the world of traditional documentation to community conversation include: * Writer Bob Bringhurst's blog about Adobe InDesign and InCopy products and Adobe's community help * The Microsoft Development Network Community Center * ·The former Sun (now Oracle) OpenDS wiki, NetBeans Ruby and other community approaches to engage diverse audiences using screencasts, wikis, and blogs. * Cisco's customer support wiki, EMC's community, as well as Symantec and Intuit's approaches * The efforts of Ubuntu, Mozilla, and the FLOSS community generally Adobe Writer Bob Bringhurst's Blog Oracle is not without a user community conversation too. Besides the community discussions and blogs around documentation offerings, we have the My Oracle Support Community forums, Oracle Technology Network (OTN) communities, wiki, blogs, and so on. We have the great work done by our user groups and customer councils. Employees like David Haimes are reaching out, and enthusiastic non-employee gurus like Chet Justice (OracleNerd), Floyd Teter and Eddie Awad provide great "how-to" information too. But what does this paradigm shift mean for existing technical writers as users turn away from the traditional printable PDF manual deliverables? We asked Anne after the conference. The writer role becomes one of conversation initiator or enabler. The role evolves, along with the process, as the users define their concept of user assistance and terms of engagement with the product instead of having it pre-determined. It is largely a case now of "inventing the job while you're doing it, instead of being hired for it" Anne said. There is less emphasis on formal titles. Anne mentions that her own title "Content Stacker" at OpenStack; others use titles such as "Content Curator" or "Community Lead". However, the role remains one essentially about communications, "but of a new type--interacting with users, moderating, curating content, instead of sitting down to write a manual from start to finish." Clearly then, this role is open to more than professional technical writers. Product managers who write blogs, developers who moderate forums, support professionals who update wikis, rock star programmers with a penchant for YouTube are ideal. Anyone with the product knowledge, empathy for the user, and flair for relationships on the social web can join in. Some even perform these roles already but do not realize it. Anne feels the technical communicator space will move from hiring new community conversation professionals (who are already active in the space through blogging, tweets, wikis, and so on) to retraining some existing writers over time. Our own research reveals that the established proponents of community user assistance even set employee performance objectives for internal content curators about the amount of community content delivered by people outside the organization! To take advantage of the conversations on the web as user assistance, enterprises must first establish where on the spectrum their community lies. "What is the line between community willingness to contribute and the enterprise objectives?" Anne asked. "The relationship with users must be managed and also measured." Anne believes that the process can start with a "just do it" approach. Begin by reaching out to existing user groups, individual bloggers and tweeters, forum posters, early adopter program participants, conference attendees, customer advisory board members, and so on. Use analytical tools to measure the level of conversation about your products and services to show a return on investment (ROI), winning management support. Anne emphasized that success with the community model is dependent on lowering the technical and motivational barriers so that users can readily contribute to the conversation. Simple tools must be provided, and guidelines, if any, must be straightforward but not mandatory. The conversational approach is one where traditional style and branding guides do not necessarily apply. Tools and infrastructure help users to create content easily, to search and find the information online, read it, rate it, translate it, and participate further in the content's evolution. Recognizing contributors by using ratings on forums, giving out Twitter kudos, conference invitations, visits to headquarters, free products, preview releases, and so on, also encourages the adoption of the conversation model. The move to conversation as user assistance is not free, but there is a business ROI. The conversational model means that customer service is enhanced, as user experience moves from a functional to a valued, emotional level. Studies show a positive correlation between loyalty and financial performance (Consortium for Service Innovation, 2010), and as customer experience and loyalty become key differentiators, user experience professionals cannot explore the model's possibilities. The digital universe (measured at 1.2 million petabytes in 2010) is doubling every 12 to 18 months, and 70 percent of that universe consists of user-generated content (IDC, 2010). Conversation as user assistance cannot be ignored but must be embraced. It is a time to manage for abundance, not scarcity. Besides, the conversation approach certainly sounds more interesting, rewarding, and fun than the traditional model! I would like to thank Anne for her time and thoughts, and recommend that all user assistance professionals read her book. You can follow Anne on Twitter at: http://www.twitter.com/annegentle. Oracle's Acrolinx IQ deployment was used to author this article.

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• Building KPIs to monitor your business Its not really about the Technology

  When I have discussions with people about Business Intelligence, one of the questions the inevitably come up is about building KPIs and how to accomplish that. From a technical level the concept of a KPI is very simple, almost too simple in that it is like the tip of an iceberg floating above the water. The key to that iceberg is not really the tip, but the mass of the iceberg that is hidden beneath the surface upon which the tip sits. The analogy of the iceberg is not meant to indicate that the foundation of the KPI is overly difficult or complex. The disparity in size in meant to indicate that the larger thing that needs to be defined is not the technical tip, but the underlying business definition of what the KPI means. From a technical perspective the KPI consists of primarily the following items: Actual Value This is the actual value data point that is being measured. An example would be something like the amount of sales. Target Value This is the target goal for the KPI. This is a number that can be measured against Actual Value. An example would be $10,000 in monthly sales. Target Indicator Range This is the definition of ranges that define what type of indicator the user will see comparing the Actual Value to the Target Value. Most often this is defined by stoplight, but can be any indicator that is going to show a status in a quick fashion to the user. Typically this would be something like: Red Light = Actual Value more than 5% below target; Yellow Light = Within 5% of target either direction; Green Light = More than 5% higher than Target Value Status\Trend Indicator This is an optional attribute of a KPI that is typically used to show some kind of trend. The vast majority of these indicators are used to show some type of progress against a previous period. As an example, the status indicator might be used to show how the monthly sales compare to last month. With this type of indicator there needs to be not only a definition of what the ranges are for your status indictor, but then also what value the number needs to be compared against. So now we have an idea of what data points a KPI consists of from a technical perspective lets talk a bit about tools. As you can see technically there is not a whole lot to them and the choice of technology is not as important as the definition of the KPIs, which we will get to in a minute. There are many different types of tools in the Microsoft BI stack that you can use to expose your KPI to the business. These include Performance Point, SharePoint, Excel, and SQL Reporting Services. There are pluses and minuses to each technology and the right technology is based a lot on your goals and how you want to deliver the information to the users. Additionally, there are other non-Microsoft tools that can be used to expose KPI indicators to your business users. Regardless of the technology used as your front end, the heavy lifting of KPI is in the business definition of the values and benchmarks for that KPI. The discussion about KPIs is very dependent on the history of an organization and how much they are exposed to the attributes of a KPI. Often times when discussing KPIs with a business contact who has not been exposed to KPIs the discussion tends to also be a session educating the business user about what a KPI is and what goes into the definition of a KPI. The majority of times the business user has an idea of what their actual values are and they have been tracking those numbers for some time, generally in Excel and all manually. So they will know the amount of sales last month along with sales two years ago in the same month. Where the conversation tends to get stuck is when you start discussing what the target value should be. The actual value is answering the What and How much questions. When you are talking about the Target values you are asking the question Is this number good or bad. Typically, the user will know whether or not the value is good or bad, but most of the time they are not able to quantify what is good or bad. Their response is usually something like I just know. Because they have been watching the sales quantity for years now, they can tell you that a 5% decrease in sales this month might actually be a good thing, maybe because the salespeople are all waiting until next month when the new versions come out. It can sometimes be very hard to break the business people of this habit. One of the fears generally is that the status indicator is not subjective. Thus, in the scenario above, the business user is going to be fearful that their boss, just looking at a negative red indicator, is going to haul them out to the woodshed for a bad month. But, on the flip side, if all you are displaying is the amount of sales, only a person with knowledge of last month sales and the target amount for this month would have any idea if $10,000 in sales is good or not. Here is where a key point about KPIs needs to be communicated to both the business user and any user who might be viewing the results of that KPI. The KPI is just one tool that is used to report on business performance. The KPI is meant as a quick indicator of one business statistic. It is not meant to tell the entire story. It does not answer the question Why. Its primary purpose is to objectively and quickly expose an area of the business that might warrant more review. There is always going to be the need to do further analysis on any potential negative or neutral KPI. So, hopefully, once you have convinced your business user to come up with some target numbers and ranges for status indicators, you then need to take the next step and help them answer the Why question. The main question here to ask is, Okay, you see the indicator and you need to discover why the number is what is, where do you go?. The answer is usually a combination of sources. A sales manager might have some of the following items at their disposal (Marketing report showing a decrease in the promotional discounts for the month, Pricing Report showing the reduction of prices of older models, an Inventory Report showing the discontinuation of a particular product line, or a memo showing the ending of a large affiliate partnership. The answers to the question Why are never as simple as a single indicator value. Bring able to quickly get to this information is all about designing how a user accesses the KPIs and then also how easily they can get to the additional information they need. This is where a Dashboard mentality can come in handy. For example, the business user can have a dashboard that shows their KPIs, but also has links to some of the common reports that they run regarding Sales Data. The users boss may have the same KPIs on their dashboard, but instead of links to individual reports they are going to have a link to a status report that was created by the user that pulls together all the data about the KPI in a summary format the users boss can review. So some of the key things to think about when building or evaluating KPIs for your organization: Technology should not be the driving factor KPIs are of little value without some indicator for whether a value is good, bad or neutral. KPIs only give an answer to the Is this number good\bad? question Make sure the ability to drill into the Why of a KPI is close at hand and relevant to the user who is viewing the KPI. The KPI is a key business tool when defined properly to help monitor business performance across the enterprise in an objective and consistent manner. At times it might feel like the process of defining the business aspects of a KPI can sometimes be arduous, the payoff in the end can far outweigh the costs. Some of the benefits of going through this process are a better understanding of the key metrics for an organization and the measure of those metrics and a consistent snapshot of business performance that can be utilized across the organization. And I think that these are benefits to any organization regardless of the technology or the implementation.Did you know that DotNetSlackers also publishes .net articles written by top known .net Authors? We already have over 80 articles in several categories including Silverlight. Take a look: here.

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• Diagnosing ADF Mobile iOS deployment problems

  - by Chris Muir

  From time to time I encounter customers who have taken possession of a brand new Apple Mac, have that excited "I've just spent more on a computer then I ever wanted to but it's okay" crazy gleam in their eye, but on pre-loading all the necessary software for Oracle's ADF Mobile to start their mobile campaign, following Oracle's setup instructions and deploying their first app to Apple's XCode iPhone Simulator they hit this error message in the JDeveloper Log-Deployment window: [01:36:46 PM] Deployment cancelled. [01:36:46 PM] ----  Deployment incomplete  ----. [01:36:46 PM] Failed to build the iOS application bundle. [01:36:46 PM] Deployment failed due to one or more errors returned by '/Applications/Xcode.app/Contents/Developer/usr/bin/xcodebuild'.  The following is a summary of the returned error(s): Command-line execution failed (Return code: 69) "Oh, return code 69, I know that well" I hear you say.  Admittedly the error code is less than useful besides drawing some titters from the peanut gallery. Before explaining what's gone wrong, I think it's useful to teach customers how to diagnose these issues themselves.  When ADF Mobile commences a deployment, be it to Apple's iOS or Google's Android platforms, JDeveloper and ADF Mobile do a good job in the Log window of showing you what the deployment process entails.  In the case of deploying to iOS the log window will literally include the XCode commands executed to complete the deployment cycle. As example here's the log output that was produced before the error message was raised.... take the opportunity to read this line by line and note the command line calls highlighted in blue: (Note some of the following lines have been split over multiple lines to suit reading on this blog, each original line is preceded by a timestamp. Ensure to check the exact commands from JDev) [01:36:33 PM] Target platform is (iOS). [01:36:33 PM] Beginning deployment of ADF Mobile application 'LayoutDemo' to iOS using profile 'IOS_MOBILE_NATIVE_archive1'. [01:36:34 PM] Command-line executed: [/Applications/Xcode.app/Contents/Developer/usr/bin/xcodebuild, -version] [01:36:34 PM] Command-line execution succeeded. [01:36:34 PM] Running dependency analysis... [01:36:34 PM] Building... [01:36:34 PM] Deploying 3 profiles... [01:36:35 PM] Wrote Archive Module to /Users/chris/fmw/jdeveloper/jdev/extensions/ oracle.adf.mobile/Samples/PublicSamples/LayoutDemo/ApplicationController/ deploy/ApplicationController.jar [01:36:35 PM] WARNING: No Resource Catalog enabled ADF components found to package [01:36:36 PM] Wrote Archive Module to /Users/chris/fmw/jdeveloper/jdev/extensions/ oracle.adf.mobile/Samples/PublicSamples/LayoutDemo/ViewController/ deploy/ViewController.jar [01:36:36 PM] Verifying existence of the .adf source directory of the ADF Mobile application... [01:36:36 PM] Verifying Application Controller project exists... [01:36:36 PM] Verifying application dependencies... [01:36:36 PM] The application may not function correctly because the following dependent libraries are missing: /Users/chris/jdev/jdeveloper/jdeveloper/jdev/extensions/oracle.adf.mobile/ lib/adfmf.springboard.jar [01:36:36 PM] Verifying project dependencies... [01:36:36 PM] Validating application XML files... [01:36:36 PM] Validating XML files in project ApplicationController... [01:36:36 PM] Validating XML files in project ViewController... [01:36:40 PM] Copying common javascript files... [01:36:41 PM] Copying FARs to the ADF Mobile Framework application... [01:36:41 PM] Extracting Feature Archive file, "ApplicationController.jar" to deployment folder, "ApplicationController". [01:36:42 PM] Extracting Feature Archive file, "ViewController.jar" to deployment folder, "ViewController". [01:36:42 PM] Deploying skinning files... [01:36:43 PM] Copying the CVM SDK files built for the x86 processor... [01:36:43 PM] Copying the CVM JDK files built for the x86 processor... [01:36:43 PM] Command-line executed: [cp, -R, -p, /Users/chris/fmw/jdeveloper/jdev/extensions/oracle.adf.mobile/iOS/jvmti/x86/, /Users/chris/fmw/jdeveloper/jdev/extensions/oracle.adf.mobile/ Samples/PublicSamples/ LayoutDemo/deploy/IOS_MOBILE_NATIVE_archive1/temporary_xcode_project/lib] [01:36:43 PM] Command-line execution succeeded. [01:36:43 PM] Command-line executed: [cp, -R, -p, /Users/chris/fmw/jdeveloper/jdev/extensions/oracle.adf.mobile/iOS/jvmti/jar/, /Users/chris/fmw/jdeveloper/jdev/extensions/oracle.adf.mobile/Samples/ PublicSamples/LayoutDemo/deploy/IOS_MOBILE_NATIVE_archive1/ temporary_xcode_project/lib] [01:36:43 PM] Command-line execution succeeded. [01:36:43 PM] Copying security related files to the ADF Mobile Framework application... [01:36:44 PM] Command-line executed from path: /Users/chris/fmw/jdeveloper/jdev/extensions/oracle.adf.mobile/Samples/ PublicSamples/LayoutDemo/deploy/IOS_MOBILE_NATIVE_archive1/temporary_xcode_project/ [01:36:44 PM] Command-line executed: /Applications/Xcode.app/Contents/Developer/usr/bin/xcodebuild clean install -configuration Debug -sdk /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneSimulator.platform/ Developer/SDKs/iPhoneSimulator6.1.sdk DSTROOT=/Users/chris/fmw/jdeveloper/jdev/extensions/oracle.adf.mobile/Samples/ PublicSamples/LayoutDemo/deploy/IOS_MOBILE_NATIVE_archive1/Destination_Root/ IPHONEOS_DEPLOYMENT_TARGET=5.0 TARGETED_DEVICE_FAMILY=1,2 PRODUCT_NAME=LayoutDemo ADD_SETTINGS_BUNDLE=NO As you can see when we move from JDeveloper undertaking its work, it then passes the code off in the last few lines for Apple's XCode to assemble and deploy the required .ipa file.  From the original error message which followed this complaining about xcodebuild failing with return code 69, we can quickly see the exact command line used to call xcodebuild. As this is the exact command line call with all its options, you're free to open a Terminal window in Mac OSX and execute the same command by simply copying and pasting the command line. And via this you'll then find out what return code actually 69 means.  Unfortunately it's not that exciting. For Macs that have just been installed and configured with XCode, XCode (and for that matter iTunes) which is required by ADF Mobile to deploy must have been run at least once before hand on your brand new Mac (to be clear that's once ever, not once every restart). On doing so you will be presented with a license agreement from Apple that you must accept. Only once you've done this will the command line calls work.  They're currently failing as you haven't accepted the legal terms and conditions. (arguably you an also accept the terms and conditions from the command line too, but ADF Mobile cannot do this on your behalf, so it's just easier to open the tools and confirm the legal requirements that way). Putting aside the error code and its meaning, watching the log window, watching what commands are executed, learning what they do, this will assist you to diagnose issues yourself and solve these sort of issues more relatively quickly.  From my perspective as an Oracle Product Manager, it allows me to say "this is the stuff you don't need to worry about when you use ADF Mobile when it's configured correctly" .... as you can see my salesman qualities shine through. For anyone who is happily using ADF Mobile on a Mac and wondering why you didn't hit these issues, it's quite likely that you already accepted the license conditions before deploying via ADF Mobile.  For instance, though I'm not a fan of iTunes itself, iTunes was one of the first things I loaded on my Mac to access my Justin Bieber albums. Image courtesy of winnond / FreeDigitalPhotos.net

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• SQL SERVER – Faster SQL Server Databases and Applications – Power and Control with SafePeak Caching Options

  - by Pinal Dave

  Update: This blog post is written based on the SafePeak, which is available for free download. Today, I’d like to examine more closely one of my preferred technologies for accelerating SQL Server databases, SafePeak. Safepeak’s software provides a variety of advanced data caching options, techniques and tools to accelerate the performance and scalability of SQL Server databases and applications. I’d like to look more closely at some of these options, as some of these capabilities could help you address lagging database and performance on your systems. To better understand the available options, it is best to start by understanding the difference between the usual “Basic Caching” vs. SafePeak’s “Dynamic Caching”. Basic Caching Basic Caching (or the stale and static cache) is an ability to put the results from a query into cache for a certain period of time. It is based on TTL, or Time-to-live, and is designed to stay in cache no matter what happens to the data. For example, although the actual data can be modified due to DML commands (update/insert/delete), the cache will still hold the same obsolete query data. Meaning that with the Basic Caching is really static / stale cache.  As you can tell, this approach has its limitations. Dynamic Caching Dynamic Caching (or the non-stale cache) is an ability to put the results from a query into cache while maintaining the cache transaction awareness looking for possible data modifications. The modifications can come as a result of: DML commands (update/insert/delete), indirect modifications due to triggers on other tables, executions of stored procedures with internal DML commands complex cases of stored procedures with multiple levels of internal stored procedures logic. When data modification commands arrive, the caching system identifies the related cache items and evicts them from cache immediately. In the dynamic caching option the TTL setting still exists, although its importance is reduced, since the main factor for cache invalidation (or cache eviction) become the actual data updates commands. Now that we have a basic understanding of the differences between “basic” and “dynamic” caching, let’s dive in deeper. SafePeak: A comprehensive and versatile caching platform SafePeak comes with a wide range of caching options. Some of SafePeak’s caching options are automated, while others require manual configuration. Together they provide a complete solution for IT and Data managers to reach excellent performance acceleration and application scalability for  a wide range of business cases and applications. Automated caching of SQL Queries: Fully/semi-automated caching of all “read” SQL queries, containing any types of data, including Blobs, XMLs, Texts as well as all other standard data types. SafePeak automatically analyzes the incoming queries, categorizes them into SQL Patterns, identifying directly and indirectly accessed tables, views, functions and stored procedures; Automated caching of Stored Procedures: Fully or semi-automated caching of all read” stored procedures, including procedures with complex sub-procedure logic as well as procedures with complex dynamic SQL code. All procedures are analyzed in advance by SafePeak’s  Metadata-Learning process, their SQL schemas are parsed – resulting with a full understanding of the underlying code, objects dependencies (tables, views, functions, sub-procedures) enabling automated or semi-automated (manually review and activate by a mouse-click) cache activation, with full understanding of the transaction logic for cache real-time invalidation; Transaction aware cache: Automated cache awareness for SQL transactions (SQL and in-procs); Dynamic SQL Caching: Procedures with dynamic SQL are pre-parsed, enabling easy cache configuration, eliminating SQL Server load for parsing time and delivering high response time value even in most complicated use-cases; Fully Automated Caching: SQL Patterns (including SQL queries and stored procedures) that are categorized by SafePeak as “read and deterministic” are automatically activated for caching; Semi-Automated Caching: SQL Patterns categorized as “Read and Non deterministic” are patterns of SQL queries and stored procedures that contain reference to non-deterministic functions, like getdate(). Such SQL Patterns are reviewed by the SafePeak administrator and in usually most of them are activated manually for caching (point and click activation); Fully Dynamic Caching: Automated detection of all dependent tables in each SQL Pattern, with automated real-time eviction of the relevant cache items in the event of “write” commands (a DML or a stored procedure) to one of relevant tables. A default setting; Semi Dynamic Caching: A manual cache configuration option enabling reducing the sensitivity of specific SQL Patterns to “write” commands to certain tables/views. An optimization technique relevant for cases when the query data is either known to be static (like archive order details), or when the application sensitivity to fresh data is not critical and can be stale for short period of time (gaining better performance and reduced load); Scheduled Cache Eviction: A manual cache configuration option enabling scheduling SQL Pattern cache eviction based on certain time(s) during a day. A very useful optimization technique when (for example) certain SQL Patterns can be cached but are time sensitive. Example: “select customers that today is their birthday”, an SQL with getdate() function, which can and should be cached, but the data stays relevant only until 00:00 (midnight); Parsing Exceptions Management: Stored procedures that were not fully parsed by SafePeak (due to too complex dynamic SQL or unfamiliar syntax), are signed as “Dynamic Objects” with highest transaction safety settings (such as: Full global cache eviction, DDL Check = lock cache and check for schema changes, and more). The SafePeak solution points the user to the Dynamic Objects that are important for cache effectiveness, provides easy configuration interface, allowing you to improve cache hits and reduce cache global evictions. Usually this is the first configuration in a deployment; Overriding Settings of Stored Procedures: Override the settings of stored procedures (or other object types) for cache optimization. For example, in case a stored procedure SP1 has an “insert” into table T1, it will not be allowed to be cached. However, it is possible that T1 is just a “logging or instrumentation” table left by developers. By overriding the settings a user can allow caching of the problematic stored procedure; Advanced Cache Warm-Up: Creating an XML-based list of queries and stored procedure (with lists of parameters) for periodically automated pre-fetching and caching. An advanced tool allowing you to handle more rare but very performance sensitive queries pre-fetch them into cache allowing high performance for users’ data access; Configuration Driven by Deep SQL Analytics: All SQL queries are continuously logged and analyzed, providing users with deep SQL Analytics and Performance Monitoring. Reduce troubleshooting from days to minutes with database objects and SQL Patterns heat-map. The performance driven configuration helps you to focus on the most important settings that bring you the highest performance gains. Use of SafePeak SQL Analytics allows continuous performance monitoring and analysis, easy identification of bottlenecks of both real-time and historical data; Cloud Ready: Available for instant deployment on Amazon Web Services (AWS). As you can see, there are many options to configure SafePeak’s SQL Server database and application acceleration caching technology to best fit a lot of situations. If you’re not familiar with their technology, they offer free-trial software you can download that comes with a free “help session” to help get you started. You can access the free trial here. Also, SafePeak is available to use on Amazon Cloud. Reference: Pinal Dave (http://blog.sqlauthority.com)Filed under: PostADay, SQL, SQL Authority, SQL Performance, SQL Query, SQL Server, SQL Tips and Tricks, T SQL

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• CI Deployment Of Azure Web Roles Using TeamCity

  - by srkirkland

  After recently migrating an important new website to use Windows Azure “Web Roles” I wanted an easier way to deploy new versions to the Azure Staging environment as well as a reliable process to rollback deployments to a certain “known good” source control commit checkpoint.  By configuring our JetBrains’ TeamCity CI server to utilize Windows Azure PowerShell cmdlets to create new automated deployments, I’ll show you how to take control of your Azure publish process. Step 0: Configuring your Azure Project in Visual Studio Before we can start looking at automating the deployment, we should make sure manual deployments from Visual Studio are working properly.  Detailed information for setting up deployments can be found at http://msdn.microsoft.com/en-us/library/windowsazure/ff683672.aspx#PublishAzure or by doing some quick Googling, but the basics are as follows: Install the prerequisite Windows Azure SDK Create an Azure project by right-clicking on your web project and choosing “Add Windows Azure Cloud Service Project” (or by manually adding that project type) Configure your Role and Service Configuration/Definition as desired Right-click on your azure project and choose “Publish,” create a publish profile, and push to your web role You don’t actually have to do step #4 and create a publish profile, but it’s a good exercise to make sure everything is working properly.  Once your Windows Azure project is setup correctly, we are ready to move on to understanding the Azure Publish process. Understanding the Azure Publish Process The actual Windows Azure project is fairly simple at its core—it builds your dependent roles (in our case, a web role) against a specific service and build configuration, and outputs two files: ServiceConfiguration.Cloud.cscfg: This is just the file containing your package configuration info, for example Instance Count, OsFamily, ConnectionString and other Setting information. ProjectName.Azure.cspkg: This is the package file that contains the guts of your deployment, including all deployable files. When you package your Azure project, these two files will be created within the directory ./[ProjectName].Azure/bin/[ConfigName]/app.publish/.  If you want to build your Azure Project from the command line, it’s as simple as calling MSBuild on the “Publish” target: msbuild.exe /target:Publish Windows Azure PowerShell Cmdlets The last pieces of the puzzle that make CI automation possible are the Azure PowerShell Cmdlets (http://msdn.microsoft.com/en-us/library/windowsazure/jj156055.aspx).  These cmdlets are what will let us create deployments without Visual Studio or other user intervention. Preparing TeamCity for Azure Deployments Now we are ready to get our TeamCity server setup so it can build and deploy Windows Azure projects, which we now know requires the Azure SDK and the Windows Azure PowerShell Cmdlets. Installing the Azure SDK is easy enough, just go to https://www.windowsazure.com/en-us/develop/net/ and click “Install” Once this SDK is installed, I recommend running a test build to make sure your project is building correctly.  You’ll want to setup your build step using MSBuild with the “Publish” target against your solution file.  Mine looks like this: Assuming the build was successful, you will now have the two *.cspkg and *cscfg files within your build directory.  If the build was red (failed), take a look at the build logs and keep an eye out for “unsupported project type” or other build errors, which will need to be addressed before the CI deployment can be completed. With a successful build we are now ready to install and configure the Windows Azure PowerShell Cmdlets: Follow the instructions at http://msdn.microsoft.com/en-us/library/windowsazure/jj554332 to install the Cmdlets and configure PowerShell After installing the Cmdlets, you’ll need to get your Azure Subscription Info using the Get-AzurePublishSettingsFile command. Store the resulting *.publishsettings file somewhere you can get to easily, like C:\TeamCity, because you will need to reference it later from your deploy script. Scripting the CI Deploy Process Now that the cmdlets are installed on our TeamCity server, we are ready to script the actual deployment using a TeamCity “PowerShell” build runner.  Before we look at any code, here’s a breakdown of our deployment algorithm: Setup your variables, including the location of the *.cspkg and *cscfg files produced in the earlier MSBuild step (remember, the folder is something like [ProjectName].Azure/bin/[ConfigName]/app.publish/ Import the Windows Azure PowerShell Cmdlets Import and set your Azure Subscription information (this is basically your authentication/authorization step, so protect your settings file Now look for a current deployment, and if you find one Upgrade it, else Create a new deployment Pretty simple and straightforward.  Now let’s look at the code (also available as a gist here: https://gist.github.com/3694398): $subscription = "[Your Subscription Name]" $service = "[Your Azure Service Name]" $slot = "staging" #staging or production $package = "[ProjectName]\bin\[BuildConfigName]\app.publish\[ProjectName].cspkg" $configuration = "[ProjectName]\bin\[BuildConfigName]\app.publish\ServiceConfiguration.Cloud.cscfg" $timeStampFormat = "g" $deploymentLabel = "ContinuousDeploy to $service v%build.number%"   Write-Output "Running Azure Imports" Import-Module "C:\Program Files (x86)\Microsoft SDKs\Windows Azure\PowerShell\Azure\*.psd1" Import-AzurePublishSettingsFile "C:\TeamCity\[PSFileName].publishsettings" Set-AzureSubscription -CurrentStorageAccount $service -SubscriptionName $subscription   function Publish(){ $deployment = Get-AzureDeployment -ServiceName $service -Slot $slot -ErrorVariable a -ErrorAction silentlycontinue   if ($a[0] -ne $null) { Write-Output "$(Get-Date -f $timeStampFormat) - No deployment is detected. Creating a new deployment. " } if ($deployment.Name -ne $null) { #Update deployment inplace (usually faster, cheaper, won't destroy VIP) Write-Output "$(Get-Date -f $timeStampFormat) - Deployment exists in $servicename. Upgrading deployment." UpgradeDeployment } else { CreateNewDeployment } }   function CreateNewDeployment() { write-progress -id 3 -activity "Creating New Deployment" -Status "In progress" Write-Output "$(Get-Date -f $timeStampFormat) - Creating New Deployment: In progress"   $opstat = New-AzureDeployment -Slot $slot -Package $package -Configuration $configuration -label $deploymentLabel -ServiceName $service   $completeDeployment = Get-AzureDeployment -ServiceName $service -Slot $slot $completeDeploymentID = $completeDeployment.deploymentid   write-progress -id 3 -activity "Creating New Deployment" -completed -Status "Complete" Write-Output "$(Get-Date -f $timeStampFormat) - Creating New Deployment: Complete, Deployment ID: $completeDeploymentID" }   function UpgradeDeployment() { write-progress -id 3 -activity "Upgrading Deployment" -Status "In progress" Write-Output "$(Get-Date -f $timeStampFormat) - Upgrading Deployment: In progress"   # perform Update-Deployment $setdeployment = Set-AzureDeployment -Upgrade -Slot $slot -Package $package -Configuration $configuration -label $deploymentLabel -ServiceName $service -Force   $completeDeployment = Get-AzureDeployment -ServiceName $service -Slot $slot $completeDeploymentID = $completeDeployment.deploymentid   write-progress -id 3 -activity "Upgrading Deployment" -completed -Status "Complete" Write-Output "$(Get-Date -f $timeStampFormat) - Upgrading Deployment: Complete, Deployment ID: $completeDeploymentID" }   Write-Output "Create Azure Deployment" Publish   Creating the TeamCity Build Step The only thing left is to create a second build step, after your MSBuild “Publish” step, with the build runner type “PowerShell”.  Then set your script to “Source Code,” the script execution mode to “Put script into PowerShell stdin with “-Command” arguments” and then copy/paste in the above script (replacing the placeholder sections with your values).  This should look like the following:   Wrap Up After combining the MSBuild /target:Publish step (which creates the necessary Windows Azure *.cspkg and *.cscfg files) and a PowerShell script step which utilizes the Azure PowerShell Cmdlets, we have a fully deployable build configuration in TeamCity.  You can configure this step to run whenever you’d like using build triggers – for example, you could even deploy whenever a new master branch deploy comes in and passes all required tests. In the script I’ve hardcoded that every deployment goes to the Staging environment on Azure, but you could deploy straight to Production if you want to, or even setup a deployment configuration variable and set it as desired. After your TeamCity Build Configuration is complete, you’ll see something that looks like this: Whenever you click the “Run” button, all of your code will be compiled, published, and deployed to Windows Azure! One additional enormous benefit of automating the process this way is that you can easily deploy any specific source control changeset by clicking the little ellipsis button next to "Run.”  This will bring up a dialog like the one below, where you can select the last change to use for your deployment.  Since Azure Web Role deployments don’t have any rollback functionality, this is a critical feature.   Enjoy!

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• Security in Software

  The term security has many meanings based on the context and perspective in which it is used. Security from the perspective of software/system development is the continuous process of maintaining confidentiality, integrity, and availability of a system, sub-system, and system data. This definition at a very high level can be restated as the following: Computer security is a continuous process dealing with confidentiality, integrity, and availability on multiple layers of a system. Key Aspects of Software Security Integrity Confidentiality Availability Integrity within a system is the concept of ensuring only authorized users can only manipulate information through authorized methods and procedures. An example of this can be seen in a simple lead management application.  If the business decided to allow each sales member to only update their own leads in the system and sales managers can update all leads in the system then an integrity violation would occur if a sales member attempted to update someone else’s leads. An integrity violation occurs when a team member attempts to update someone else’s lead because it was not entered by the sales member.  This violates the business rule that leads can only be update by the originating sales member. Confidentiality within a system is the concept of preventing unauthorized access to specific information or tools.  In a perfect world the knowledge of the existence of confidential information/tools would be unknown to all those who do not have access. When this this concept is applied within the context of an application only the authorized information/tools will be available. If we look at the sales lead management system again, leads can only be updated by originating sales members. If we look at this rule then we can say that all sales leads are confidential between the system and the sales person who entered the lead in to the system. The other sales team members would not need to know about the leads let alone need to access it. Availability within a system is the concept of authorized users being able to access the system. A real world example can be seen again from the lead management system. If that system was hosted on a web server then IP restriction can be put in place to limit access to the system based on the requesting IP address. If in this example all of the sales members where accessing the system from the 192.168.1.23 IP address then removing access from all other IPs would be need to ensure that improper access to the system is prevented while approved users can access the system from an authorized location. In essence if the requesting user is not coming from an authorized IP address then the system will appear unavailable to them. This is one way of controlling where a system is accessed. Through the years several design principles have been identified as being beneficial when integrating security aspects into a system. These principles in various combinations allow for a system to achieve the previously defined aspects of security based on generic architectural models. Security Design Principles Least Privilege Fail-Safe Defaults Economy of Mechanism Complete Mediation Open Design Separation Privilege Least Common Mechanism Psychological Acceptability Defense in Depth Least Privilege Design PrincipleThe Least Privilege design principle requires a minimalistic approach to granting user access rights to specific information and tools. Additionally, access rights should be time based as to limit resources access bound to the time needed to complete necessary tasks. The implications of granting access beyond this scope will allow for unnecessary access and the potential for data to be updated out of the approved context. The assigning of access rights will limit system damaging attacks from users whether they are intentional or not. This principle attempts to limit data changes and prevents potential damage from occurring by accident or error by reducing the amount of potential interactions with a resource. Fail-Safe Defaults Design PrincipleThe Fail-Safe Defaults design principle pertains to allowing access to resources based on granted access over access exclusion. This principle is a methodology for allowing resources to be accessed only if explicit access is granted to a user. By default users do not have access to any resources until access has been granted. This approach prevents unauthorized users from gaining access to resource until access is given. Economy of Mechanism Design PrincipleThe Economy of mechanism design principle requires that systems should be designed as simple and small as possible. Design and implementation errors result in unauthorized access to resources that would not be noticed during normal use. Complete Mediation Design PrincipleThe Complete Mediation design principle states that every access to every resource must be validated for authorization. Open Design Design PrincipleThe Open Design Design Principle is a concept that the security of a system and its algorithms should not be dependent on secrecy of its design or implementation Separation Privilege Design PrincipleThe separation privilege design principle requires that all resource approved resource access attempts be granted based on more than a single condition. For example a user should be validated for active status and has access to the specific resource. Least Common Mechanism Design PrincipleThe Least Common Mechanism design principle declares that mechanisms used to access resources should not be shared. Psychological Acceptability Design PrincipleThe Psychological Acceptability design principle refers to security mechanisms not make resources more difficult to access than if the security mechanisms were not present Defense in Depth Design PrincipleThe Defense in Depth design principle is a concept of layering resource access authorization verification in a system reduces the chance of a successful attack. This layered approach to resource authorization requires unauthorized users to circumvent each authorization attempt to gain access to a resource. When designing a system that requires meeting a security quality attribute architects need consider the scope of security needs and the minimum required security qualities. Not every system will need to use all of the basic security design principles but will use one or more in combination based on a company’s and architect’s threshold for system security because the existence of security in an application adds an additional layer to the overall system and can affect performance. That is why the definition of minimum security acceptably is need when a system is design because this quality attributes needs to be factored in with the other system quality attributes so that the system in question adheres to all qualities based on the priorities of the qualities. Resources: Barnum, Sean. Gegick, Michael. (2005). Least Privilege. Retrieved on August 28, 2011 from https://buildsecurityin.us-cert.gov/bsi/articles/knowledge/principles/351-BSI.html Saltzer, Jerry. (2011). BASIC PRINCIPLES OF INFORMATION PROTECTION. Retrieved on August 28, 2011 from  http://web.mit.edu/Saltzer/www/publications/protection/Basic.html Barnum, Sean. Gegick, Michael. (2005). Defense in Depth. Retrieved on August 28, 2011 from  https://buildsecurityin.us-cert.gov/bsi/articles/knowledge/principles/347-BSI.html Bertino, Elisa. (2005). Design Principles for Security. Retrieved on August 28, 2011 from  http://homes.cerias.purdue.edu/~bhargav/cs526/security-9.pdf

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• SQL SERVER – Thinking about Deprecated, Discontinued Features and Breaking Changes while Upgrading to SQL Server 2012 – Guest Post by Nakul Vachhrajani

  - by pinaldave

  Nakul Vachhrajani is a Technical Specialist and systems development professional with iGATE having a total IT experience of more than 7 years. Nakul is an active blogger with BeyondRelational.com (150+ blogs), and can also be found on forums at SQLServerCentral and BeyondRelational.com. Nakul has also been a guest columnist for SQLAuthority.com and SQLServerCentral.com. Nakul presented a webcast on the “Underappreciated Features of Microsoft SQL Server” at the Microsoft Virtual Tech Days Exclusive Webcast series (May 02-06, 2011) on May 06, 2011. He is also the author of a research paper on Database upgrade methodologies, which was published in a CSI journal, published nationwide. In addition to his passion about SQL Server, Nakul also contributes to the academia out of personal interest. He visits various colleges and universities as an external faculty to judge project activities being carried out by the students. Disclaimer: The opinions expressed herein are his own personal opinions and do not represent his employer’s view in anyway. Blog | LinkedIn | Twitter | Google+ Let us hear the thoughts of Nakul in first person - Those who have been following my blogs would be aware that I am recently running a series on the database engine features that have been deprecated in Microsoft SQL Server 2012. Based on the response that I have received, I was quite surprised to know that most of the audience found these to be breaking changes, when in fact, they were not! It was then that I decided to write a little piece on how to plan your database upgrade such that it works with the next version of Microsoft SQL Server. Please note that the recommendations made in this article are high-level markers and are intended to help you think over the specific steps that you would need to take to upgrade your database. Refer the documentation – Understand the terms Change is the only constant in this world. Therefore, whenever customer requirements, newer architectures and designs require software vendors to make a change to the keywords, functions, etc; they ensure that they provide their end users sufficient time to migrate over to the new standards before dropping off the old ones. Microsoft does that too with it’s Microsoft SQL Server product. Whenever a new SQL Server release is announced, it comes with a list of the following features: Breaking changes These are changes that would break your currently running applications, scripts or functionalities that are based on earlier version of Microsoft SQL Server These are mostly features whose behavior has been changed keeping in mind the newer architectures and designs Lesson: These are the changes that you need to be most worried about! Discontinued features These features are no longer available in the associated version of Microsoft SQL Server These features used to be “deprecated” in the prior release Lesson: Without these changes, your database would not be compliant/may not work with the version of Microsoft SQL Server under consideration Deprecated features These features are those that are still available in the current version of Microsoft SQL Server, but are scheduled for removal in a future version. These may be removed in either the next version or any other future version of Microsoft SQL Server The features listed for deprecation will compose the list of discontinued features in the next version of SQL Server Lesson: Plan to make necessary changes required to remove/replace usage of the deprecated features with the latest recommended replacements Once a feature appears on the list, it moves from bottom to the top, i.e. it is first marked as “Deprecated” and then “Discontinued”. We know of “Breaking change” comes later on in the product life cycle. What this means is that if you want to know what features would not work with SQL Server 2012 (and you are currently using SQL Server 2008 R2), you need to refer the list of breaking changes and discontinued features in SQL Server 2012. Use the tools! There are a lot of tools and technologies around us, but it is rarely that I find teams using these tools religiously and to the best of their potential. Below are the top two tools, from Microsoft, that I use every time I plan a database upgrade. The SQL Server Upgrade Advisor Ever since SQL Server 2005 was announced, Microsoft provides a small, very light-weight tool called the “SQL Server upgrade advisor”. The upgrade advisor analyzes installed components from earlier versions of SQL Server, and then generates a report that identifies issues to fix either before or after you upgrade. The analysis examines objects that can be accessed, such as scripts, stored procedures, triggers, and trace files. Upgrade Advisor cannot analyze desktop applications or encrypted stored procedures. Refer the links towards the end of the post to know how to get the Upgrade Advisor. The SQL Server Profiler Another great tool that you can use is the one most SQL Server developers & administrators use often – the SQL Server profiler. SQL Server Profiler provides functionality to monitor the “Deprecation” event, which contains: Deprecation announcement – equivalent to features to be deprecated in a future release of SQL Server Deprecation final support – equivalent to features to be deprecated in the next release of SQL Server You can learn more using the links towards the end of the post. A basic checklist There are a lot of finer points that need to be taken care of when upgrading your database. But, it would be worth-while to identify a few basic steps in order to make your database compliant with the next version of SQL Server: Monitor the current application workload (on a test bed) via the Profiler in order to identify usage of features marked as Deprecated If none appear, you are all set! (This almost never happens) Note down all the offending queries and feature usages Run analysis sessions using the SQL Server upgrade advisor on your database Based on the inputs from the analysis report and Profiler trace sessions, Incorporate solutions for the breaking changes first Next, incorporate solutions for the discontinued features Revisit and document the upgrade strategy for your deployment scenarios Revisit the fall-back, i.e. rollback strategies in case the upgrades fail Because some programming changes are dependent upon the SQL server version, this may need to be done in consultation with the development teams Before any other enhancements are incorporated by the development team, send out the database changes into QA QA strategy should involve a comparison between an environment running the old version of SQL Server against the new one Because minimal application changes have gone in (essential changes for SQL Server version compliance only), this would be possible As an ongoing activity, keep incorporating changes recommended as per the deprecated features list As a DBA, update your coding standards to ensure that the developers are using ANSI compliant code – this code will require a change only if the ANSI standard changes Remember this: Change management is a continuous process. Keep revisiting the product release notes and incorporate recommended changes to stay prepared for the next release of SQL Server. May the power of SQL Server be with you! Links Referenced in this post Breaking changes in SQL Server 2012: Link Discontinued features in SQL Server 2012: Link Get the upgrade advisor from the Microsoft Download Center at: Link Upgrade Advisor page on MSDN: Link Profiler: Review T-SQL code to identify objects no longer supported by Microsoft: Link Upgrading to SQL Server 2012 by Vinod Kumar: Link Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology Tagged: Upgrade

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• Expert iptables help needed?

  - by Asad Moeen

  After a detailed analysis, I collected these details. I am under a UDP Flood which is more of application dependent. I run a Game-Server and an attacker is flooding me with "getstatus" query which makes the GameServer respond by making the replies to the query which cause output to the attacker's IP as high as 30mb/s and server lag. Here are the packet details, Packet starts with 4 bytes 0xff and then getstatus. Theoretically, the packet is like "\xff\xff\xff\xffgetstatus " Now that I've tried a lot of iptables variations like state and rate-limiting along side but those didn't work. Rate Limit works good but only when the Server is not started. As soon as the server starts, no iptables rule seems to block it. Anyone else got more solutions? someone asked me to contact the provider and get it done at the Network/Router but that looks very odd and I believe they might not do it since that would also affect other clients. Responding to all those answers, I'd say: Firstly, its a VPS so they can't do it for me. Secondly, I don't care if something is coming in but since its application generated so there has to be a OS level solution to block the outgoing packets. At least the outgoing ones must be stopped. Secondly, its not Ddos since just 400kb/s input generates 30mb/s output from my GameServer. That never happens in a D-dos. Asking the provider/hardware level solution should be used in that case but this one is different. And Yes, Banning his IP stops the flood of outgoing packets but he has many more IP-Addresses as he spoofs his original so I just need something to block him automatically. Even tried a lot of Firewalls but as you know they are just front-ends to iptables so if something doesn't work on iptables, what would the firewalls do? These were the rules I tried, iptables -A INPUT -p udp -m state --state NEW -m recent --set --name DDOS --rsource iptables -A INPUT -p udp -m state --state NEW -m recent --update --seconds 1 --hitcount 5 --name DDOS --rsource -j DROP It works for the attacks on un-used ports but when the server is listening and responding to the incoming queries by the attacker, it never works. Okay Tom.H, your rules were working when I modified them somehow like this: iptables -A INPUT -p udp -m length --length 1:1024 -m recent --set --name XXXX --rsource iptables -A INPUT -p udp -m string --string "xxxxxxxxxx" --algo bm --to 65535 -m recent --update --seconds 1 --hitcount 15 --name XXXX --rsource -j DROP They worked for about 3 days very good where the string "xxxxxxxxx" would be rate-limited, blocked if someone flooded and also didn't affect the clients. But just today, I tried updating the chain to try to remove a previously blocked IP so for that I had to flush the chain and restore this rule ( iptables -X and iptables -F ), some clients were already connected to servers including me. So restoring the rules now would also block some of the clients string completely while some are not affected. So does this mean I need to restart the server or why else would this happen because the last time the rules were working, there was no one connected?

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• Use a Fake Http Channel to Unit Test with HttpClient

  - by Steve Michelotti

  Applications get data from lots of different sources. The most common is to get data from a database or a web service. Typically, we encapsulate calls to a database in a Repository object and we create some sort of IRepository interface as an abstraction to decouple between layers and enable easier unit testing by leveraging faking and mocking. This works great for database interaction. However, when consuming a RESTful web service, this is is not always the best approach. The WCF Web APIs that are available on CodePlex (current drop is Preview 3) provide a variety of features to make building HTTP REST services more robust. When you download the latest bits, you’ll also find a new HttpClient which has been updated for .NET 4.0 as compared to the one that shipped for 3.5 in the original REST Starter Kit. The HttpClient currently provides the best API for consuming REST services on the .NET platform and the WCF Web APIs provide a number of extension methods which extend HttpClient and make it even easier to use. Let’s say you have a client application that is consuming an HTTP service – this could be Silverlight, WPF, or any UI technology but for my example I’ll use an MVC application: 1: using System; 2: using System.Net.Http; 3: using System.Web.Mvc; 4: using FakeChannelExample.Models; 5: using Microsoft.Runtime.Serialization; 6:   7: namespace FakeChannelExample.Controllers 8: { 9: public class HomeController : Controller 10: { 11: private readonly HttpClient httpClient; 12:   13: public HomeController(HttpClient httpClient) 14: { 15: this.httpClient = httpClient; 16: } 17:   18: public ActionResult Index() 19: { 20: var response = httpClient.Get("Person(1)"); 21: var person = response.Content.ReadAsDataContract<Person>(); 22:   23: this.ViewBag.Message = person.FirstName + " " + person.LastName; 24: 25: return View(); 26: } 27: } 28: } On line #20 of the code above you can see I’m performing an HTTP GET request to a Person resource exposed by an HTTP service. On line #21, I use the ReadAsDataContract() extension method provided by the WCF Web APIs to serialize to a Person object. In this example, the HttpClient is being passed into the constructor by MVC’s dependency resolver – in this case, I’m using StructureMap as an IoC and my StructureMap initialization code looks like this: 1: using StructureMap; 2: using System.Net.Http; 3:   4: namespace FakeChannelExample 5: { 6: public static class IoC 7: { 8: public static IContainer Initialize() 9: { 10: ObjectFactory.Initialize(x => 11: { 12: x.For<HttpClient>().Use(() => new HttpClient("http://localhost:31614/")); 13: }); 14: return ObjectFactory.Container; 15: } 16: } 17: } My controller code currently depends on a concrete instance of the HttpClient. Now I *could* create some sort of interface and wrap the HttpClient in this interface and use that object inside my controller instead – however, there are a few why reasons that is not desirable: For one thing, the API provided by the HttpClient provides nice features for dealing with HTTP services. I don’t really *want* these to look like C# RPC method calls – when HTTP services have REST features, I may want to inspect HTTP response headers and hypermedia contained within the message so that I can make intelligent decisions as to what to do next in my workflow (although I don’t happen to be doing these things in my example above) – this type of workflow is common in hypermedia REST scenarios. If I just encapsulate HttpClient behind some IRepository interface and make it look like a C# RPC method call, it will become difficult to take advantage of these types of things. Second, it could get pretty mind-numbing to have to create interfaces all over the place just to wrap the HttpClient. Then you’re probably going to have to hard-code HTTP knowledge into your code to formulate requests rather than just “following the links” that the hypermedia in a message might provide. Third, at first glance it might appear that we need to create an interface to facilitate unit testing, but actually it’s unnecessary. Even though the code above is dependent on a concrete type, it’s actually very easy to fake the data in a unit test. The HttpClient provides a Channel property (of type HttpMessageChannel) which allows you to create a fake message channel which can be leveraged in unit testing. In this case, what I want is to be able to write a unit test that just returns fake data. I also want this to be as re-usable as possible for my unit testing. I want to be able to write a unit test that looks like this: 1: [TestClass] 2: public class HomeControllerTest 3: { 4: [TestMethod] 5: public void Index() 6: { 7: // Arrange 8: var httpClient = new HttpClient("http://foo.com"); 9: httpClient.Channel = new FakeHttpChannel<Person>(new Person { FirstName = "Joe", LastName = "Blow" }); 10:   11: HomeController controller = new HomeController(httpClient); 12:   13: // Act 14: ViewResult result = controller.Index() as ViewResult; 15:   16: // Assert 17: Assert.AreEqual("Joe Blow", result.ViewBag.Message); 18: } 19: } Notice on line #9, I’m setting the Channel property of the HttpClient to be a fake channel. I’m also specifying the fake object that I want to be in the response on my “fake” Http request. I don’t need to rely on any mocking frameworks to do this. All I need is my FakeHttpChannel. The code to do this is not complex: 1: using System; 2: using System.IO; 3: using System.Net.Http; 4: using System.Runtime.Serialization; 5: using System.Threading; 6: using FakeChannelExample.Models; 7:   8: namespace FakeChannelExample.Tests 9: { 10: public class FakeHttpChannel<T> : HttpClientChannel 11: { 12: private T responseObject; 13:   14: public FakeHttpChannel(T responseObject) 15: { 16: this.responseObject = responseObject; 17: } 18:   19: protected override HttpResponseMessage Send(HttpRequestMessage request, CancellationToken cancellationToken) 20: { 21: return new HttpResponseMessage() 22: { 23: RequestMessage = request, 24: Content = new StreamContent(this.GetContentStream()) 25: }; 26: } 27:   28: private Stream GetContentStream() 29: { 30: var serializer = new DataContractSerializer(typeof(T)); 31: Stream stream = new MemoryStream(); 32: serializer.WriteObject(stream, this.responseObject); 33: stream.Position = 0; 34: return stream; 35: } 36: } 37: } The HttpClientChannel provides a Send() method which you can override to return any HttpResponseMessage that you want. You can see I’m using the DataContractSerializer to serialize the object and write it to a stream. That’s all you need to do. In the example above, the only thing I’ve chosen to do is to provide a way to return different response objects. But there are many more features you could add to your own re-usable FakeHttpChannel. For example, you might want to provide the ability to add HTTP headers to the message. You might want to use a different serializer other than the DataContractSerializer. You might want to provide custom hypermedia in the response as well as just an object or set HTTP response codes. This list goes on. This is the just one example of the really cool features being added to the next version of WCF to enable various HTTP scenarios. The code sample for this post can be downloaded here.

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• H1 Visa interview tips–What you must know before attending the interview?

  - by Gopinath

  USA’s H1 visa allows highly qualified professionals from other countries to work in America. Many IT professionals in India aspire to go to USA on H1 and work for their clients. Recently I had a chance to study H1 visa process to help one of my friends and I would like to share what I learned. With the assumption that your H1 petition is approved and you got an interview scheduled at US Embassy for your visa stamping, here are tips you must know before attending the interview Dress Code – Formals Say no to casuals or any fancy dress when you attend the interview. It’s not a party or friends home you are visiting. Consider H1 Visa interview as your job interview and dress up in formals. There is no option B for your, you must be in formals. A plain formal shirt with a matching pant is suggested for men. Tie and Suit would not be required, but if you are a professional at management level you can consider wearing suit. Women can wear either formal Salwar or formal pant-shirt. Avoid heavy jewellery, wear what is must as per your tradition or culture. Body Language -  Smile on your face Your body language reflects what you are and what’s going on in your mind. Don’t be nervous or restless, be relaxed and wear a beautiful smile on your face. A smile is a curve that sets everything straight. When you are called for the interview, greet the interviewer with a beautiful smile. Say Good Morning/Afternoon/Evening depending on time you are visiting them. Whenever appropriate say Thank You. Generally American professionals are very friendly people and they reciprocate for your greetings. Make sure that you make them comfortable to start the interview. Carry original documents in a separate folder I don’t want to talk much about the documents that are required for your H1B interview as it’s big subject on it’s own and it requires a separate post. I assume that your consultant or employer helped you in gathering all the required documents like – petition, DS 160 forms, education & job related documents, resume, interview call letters, client letters, etc. For all the documents you are going to submit at the interview make sure that you have originals in a separate folder.  If required interviewer may ask you show the originals of any of the document you submitted for visa processing. Don’t mix the original documents with the documents you need to submit for interview. Have a separate folder for them. For those who are going to stamping along with their spouse and children, they need to carry few extra original documents like – marriage certificate, marriage photos(30 numbers)/album, birth certificates, passports, education and profession related certificates of the spouse and children. Know your role & responsibilities The interviewer will ask you questions on your roles and responsibilities at client location. Be clear what is your day to day tasks at client place and prepared to face detailed questions on the same. When asked explain clearly and also make sure what you say is inline with what is mentioned in your petition and client invitation letter. At times they may ask you questions specific to the project/technology you are going to work. So doing some homework in this area will help you easily answer the questions. Failing to answer basic questions on your role & responsibilities may result in rejection. You work for your Employer at Client location but NOT FOR CLIENT One of the important things to keep in mind that you work for your employer and you are being deputed to client location on a work visa.  Your employer is going to be solely responsible for your salary, work, promotion, pay hikes or what so ever during your stay at USA. Your client will not be responsible for anything. Lets say you are employed with Company X in India and they are applying for H1B to work at your client(ex: Microsoft) in USA, you must keep in my mind that Microsoft is not your employer. Microsoft will not pay your salaries or responsible for any employment related activities. Company X will be solely responsible for all your employer related activities. If you don’t get this correctly and say to Visa interviewer that your client is responsible, then you may get into troubles. Know your client It’s always good to know the clients with whom you are going to work in USA and their business. If your client is a well know organisation then you may not get many questions from interviewer else you need to be well prepared to provide details like – nature of business, location, size of the organisation, etc.  Get to know the basic details about your client and be confident while providing those details to the interviewer. Also make sure that you never talk about any confidential details of your client projects and business. Revealing confidential details of your client may land your job itself in soup. Make sure that your spouse is also in sync with you If you’ve applied a H4 visa for your spouse along with your H1, make sure that spouse is in sync with you. Your spouse also should know the basic details of your job, your employer, client and location where you will be travelling. Your spouse should also be prepared to answers questions related to marriage, their profession(if working), kids, education, etc. Interviewers will try to asses your spouse communication skills, whereabouts while staying in USA and would they prefer to work USA or not. On H4, which is a dependent visa, your spouse is not allowed to work in USA and at any point your spouse should not show the intentions to search for work in USA. Less luggage more comfort You would have definitely heard that there are lot of restrictions on what you can carry along with you to an US Embassy while attending the interview. To be frank it’s not good to say there are many restrictions, but there are a hell a lot of restrictions. There are unbelievable restrictions and it’s for the safety of everyone. You are not allowed to carry mobile phones, CD/DVDs, USBs, bank cards, cameras, cosmetics, food(except baby food), water, wallets, backpacks, sealed covers, etc. Trust me most of the things we carry with us regularly every day are not allowed inside. As there are 100s of restrictions, it would be easier if you understand what you can carry along with you and just carry them alone. Ask your employer/consultant to provide you a checklist of items that you can carry. Most what you would require are H1B related documents provided by the employer/consultant Photographs All original documents supporting your H1B Passports Some cash for your travel expenses (avoid coins) Any important phone number / details written in a paper(like your cab driver number, etc.) If you carry restricted stuff then you will be stopped at security checks, you have to find people who can safely keep all the restricted items. Due to heavy restrictions in and around the US Embassy you will not find any  place to keep your luggage. So just carry the bare minimum things required so that you feel more comfortable. Useful Links THE U.S. NON IMMIGRANT VISA APPLICATION PROCESS U.S VISA SECURITY REGULATIONS GENERAL FAQS Hope this information is helpful to you and best of luck for your interview. Creative commons Image credit: Flickr/ alexfrance, vinothchandar. hughelectronic, architratan, striatic

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• NUMA-aware placement of communication variables

  - by Dave

  For classic NUMA-aware programming I'm typically most concerned about simple cold, capacity and compulsory misses and whether we can satisfy the miss by locally connected memory or whether we have to pull the line from its home node over the coherent interconnect -- we'd like to minimize channel contention and conserve interconnect bandwidth. That is, for this style of programming we're quite aware of where memory is homed relative to the threads that will be accessing it. Ideally, a page is collocated on the node with the thread that's expected to most frequently access the page, as simple misses on the page can be satisfied without resorting to transferring the line over the interconnect. The default "first touch" NUMA page placement policy tends to work reasonable well in this regard. When a virtual page is first accessed, the operating system will attempt to provision and map that virtual page to a physical page allocated from the node where the accessing thread is running. It's worth noting that the node-level memory interleaving granularity is usually a multiple of the page size, so we can say that a given page P resides on some node N. That is, the memory underlying a page resides on just one node. But when thinking about accesses to heavily-written communication variables we normally consider what caches the lines underlying such variables might be resident in, and in what states. We want to minimize coherence misses and cache probe activity and interconnect traffic in general. I don't usually give much thought to the location of the home NUMA node underlying such highly shared variables. On a SPARC T5440, for instance, which consists of 4 T2+ processors connected by a central coherence hub, the home node and placement of heavily accessed communication variables has very little impact on performance. The variables are frequently accessed so likely in M-state in some cache, and the location of the home node is of little consequence because a requester can use cache-to-cache transfers to get the line. Or at least that's what I thought. Recently, though, I was exploring a simple shared memory point-to-point communication model where a client writes a request into a request mailbox and then busy-waits on a response variable. It's a simple example of delegation based on message passing. The server polls the request mailbox, and having fetched a new request value, performs some operation and then writes a reply value into the response variable. As noted above, on a T5440 performance is insensitive to the placement of the communication variables -- the request and response mailbox words. But on a Sun/Oracle X4800 I noticed that was not the case and that NUMA placement of the communication variables was actually quite important. For background an X4800 system consists of 8 Intel X7560 Xeons . Each package (socket) has 8 cores with 2 contexts per core, so the system is 8x8x2. Each package is also a NUMA node and has locally attached memory. Every package has 3 point-to-point QPI links for cache coherence, and the system is configured with a twisted ladder "mobius" topology. The cache coherence fabric is glueless -- there's not central arbiter or coherence hub. The maximum distance between any two nodes is just 2 hops over the QPI links. For any given node, 3 other nodes are 1 hop distant and the remaining 4 nodes are 2 hops distant. Using a single request (client) thread and a single response (server) thread, a benchmark harness explored all permutations of NUMA placement for the two threads and the two communication variables, measuring the average round-trip-time and throughput rate between the client and server. In this benchmark the server simply acts as a simple transponder, writing the request value plus 1 back into the reply field, so there's no particular computation phase and we're only measuring communication overheads. In addition to varying the placement of communication variables over pairs of nodes, we also explored variations where both variables were placed on one page (and thus on one node) -- either on the same cache line or different cache lines -- while varying the node where the variables reside along with the placement of the threads. The key observation was that if the client and server threads were on different nodes, then the best placement of variables was to have the request variable (written by the client and read by the server) reside on the same node as the client thread, and to place the response variable (written by the server and read by the client) on the same node as the server. That is, if you have a variable that's to be written by one thread and read by another, it should be homed with the writer thread. For our simple client-server model that means using split request and response communication variables with unidirectional message flow on a given page. This can yield up to twice the throughput of less favorable placement strategies. Our X4800 uses the QPI 1.0 protocol with source-based snooping. Briefly, when node A needs to probe a cache line it fires off snoop requests to all the nodes in the system. Those recipients then forward their response not to the original requester, but to the home node H of the cache line. H waits for and collects the responses, adjudicates and resolves conflicts and ensures memory-model ordering, and then sends a definitive reply back to the original requester A. If some node B needed to transfer the line to A, it will do so by cache-to-cache transfer and let H know about the disposition of the cache line. A needs to wait for the authoritative response from H. So if a thread on node A wants to write a value to be read by a thread on node B, the latency is dependent on the distances between A, B, and H. We observe the best performance when the written-to variable is co-homed with the writer A. That is, we want H and A to be the same node, as the writer doesn't need the home to respond over the QPI link, as the writer and the home reside on the very same node. With architecturally informed placement of communication variables we eliminate at least one QPI hop from the critical path. Newer Intel processors use the QPI 1.1 coherence protocol with home-based snooping. As noted above, under source-snooping a requester broadcasts snoop requests to all nodes. Those nodes send their response to the home node of the location, which provides memory ordering, reconciles conflicts, etc., and then posts a definitive reply to the requester. In home-based snooping the snoop probe goes directly to the home node and are not broadcast. The home node can consult snoop filters -- if present -- and send out requests to retrieve the line if necessary. The 3rd party owner of the line, if any, can respond either to the home or the original requester (or even to both) according to the protocol policies. There are myriad variations that have been implemented, and unfortunately vendor terminology doesn't always agree between vendors or with the academic taxonomy papers. The key is that home-snooping enables the use of a snoop filter to reduce interconnect traffic. And while home-snooping might have a longer critical path (latency) than source-based snooping, it also may require fewer messages and less overall bandwidth. It'll be interesting to reprise these experiments on a platform with home-based snooping. While collecting data I also noticed that there are placement concerns even in the seemingly trivial case when both threads and both variables reside on a single node. Internally, the cores on each X7560 package are connected by an internal ring. (Actually there are multiple contra-rotating rings). And the last-level on-chip cache (LLC) is partitioned in banks or slices, which with each slice being associated with a core on the ring topology. A hardware hash function associates each physical address with a specific home bank. Thus we face distance and topology concerns even for intra-package communications, although the latencies are not nearly the magnitude we see inter-package. I've not seen such communication distance artifacts on the T2+, where the cache banks are connected to the cores via a high-speed crossbar instead of a ring -- communication latencies seem more regular.

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• We've completed the first iteration

  - by CliveT

  There are a lot of features in C# that are implemented by the compiler and not by the underlying platform. One such feature is a lambda expression. Since local variables cannot be accessed once the current method activation finishes, the compiler has to go out of its way to generate a new class which acts as a home for any variable whose lifetime needs to be extended past the activation of the procedure. Take the following example:     Random generator = new Random();     Func func = () = generator.Next(10); In this case, the compiler generates a new class called c_DisplayClass1 which is marked with the CompilerGenerated attribute. [CompilerGenerated] private sealed class c__DisplayClass1 {     // Fields     public Random generator;     // Methods     public int b__0()     {         return this.generator.Next(10);     } } Two quick comments on this: (i)    A display was the means that compilers for languages like Algol recorded the various lexical contours of the nested procedure activations on the stack. I imagine that this is what has led to the name. (ii)    It is a shame that the same attribute is used to mark all compiler generated classes as it makes it hard to figure out what they are being used for. Indeed, you could imagine optimisations that the runtime could perform if it knew that classes corresponded to certain high level concepts. We can see that the local variable generator has been turned into a field in the class, and the body of the lambda expression has been turned into a method of the new class. The code that builds the Func object simply constructs an instance of this class and initialises the fields to their initial values.     c__DisplayClass1 class2 = new c__DisplayClass1();     class2.generator = new Random();     Func func = new Func(class2.b__0); Reflector already contains code to spot this pattern of code and reproduce the form containing the lambda expression, so this is example is correctly decompiled. The use of compiler generated code is even more spectacular in the case of iterators. C# introduced the idea of a method that could automatically store its state between calls, so that it can pick up where it left off. The code can express the logical flow with yield return and yield break denoting places where the method should return a particular value and be prepared to resume.         {             yield return 1;             yield return 2;             yield return 3;         } Of course, there was already a .NET pattern for expressing the idea of returning a sequence of values with the computation proceeding lazily (in the sense that the work for the next value is executed on demand). This is expressed by the IEnumerable interface with its Current property for fetching the current value and the MoveNext method for forcing the computation of the next value. The sequence is terminated when this method returns false. The C# compiler links these two ideas together so that an IEnumerator returning method using the yield keyword causes the compiler to produce the implementation of an Iterator. Take the following piece of code.         IEnumerable GetItems()         {             yield return 1;             yield return 2;             yield return 3;         } The compiler implements this by defining a new class that implements a state machine. This has an integer state that records which yield point we should go to if we are resumed. It also has a field that records the Current value of the enumerator and a field for recording the thread. This latter value is used for optimising the creation of iterator instances. [CompilerGenerated] private sealed class d__0 : IEnumerable, IEnumerable, IEnumerator, IEnumerator, IDisposable {     // Fields     private int 1__state;     private int 2__current;     public Program 4__this;     private int l__initialThreadId; The body gets converted into the code to construct and initialize this new class. private IEnumerable GetItems() {     d__0 d__ = new d__0(-2);     d__.4__this = this;     return d__; } When the class is constructed we set the state, which was passed through as -2 and the current thread. public d__0(int 1__state) {     this.1__state = 1__state;     this.l__initialThreadId = Thread.CurrentThread.ManagedThreadId; } The state needs to be set to 0 to represent a valid enumerator and this is done in the GetEnumerator method which optimises for the usual case where the returned enumerator is only used once. IEnumerator IEnumerable.GetEnumerator() {     if ((Thread.CurrentThread.ManagedThreadId == this.l__initialThreadId)               && (this.1__state == -2))     {         this.1__state = 0;         return this;     } The state machine itself is implemented inside the MoveNext method. private bool MoveNext() {     switch (this.1__state)     {         case 0:             this.1__state = -1;             this.2__current = 1;             this.1__state = 1;             return true;         case 1:             this.1__state = -1;             this.2__current = 2;             this.1__state = 2;             return true;         case 2:             this.1__state = -1;             this.2__current = 3;             this.1__state = 3;             return true;         case 3:             this.1__state = -1;             break;     }     return false; } At each stage, the current value of the state is used to determine how far we got, and then we generate the next value which we return after recording the next state. Finally we return false from the MoveNext to signify the end of the sequence. Of course, that example was really simple. The original method body didn't have any local variables. Any local variables need to live between the calls to MoveNext and so they need to be transformed into fields in much the same way that we did in the case of the lambda expression. More complicated MoveNext methods are required to deal with resources that need to be disposed when the iterator finishes, and sometimes the compiler uses a temporary variable to hold the return value. Why all of this explanation? We've implemented the de-compilation of iterators in the current EAP version of Reflector (7). This contrasts with previous version where all you could do was look at the MoveNext method and try to figure out the control flow. There's a fair amount of things we have to do. We have to spot the use of a CompilerGenerated class which implements the Enumerator pattern. We need to go to the class and figure out the fields corresponding to the local variables. We then need to go to the MoveNext method and try to break it into the various possible states and spot the state transitions. We can then take these pieces and put them back together into an object model that uses yield return to show the transition points. After that Reflector can carry on optimising using its usual optimisations. The pattern matching is currently a little too sensitive to changes in the code generation, and we only do a limited analysis of the MoveNext method to determine use of the compiler generated fields. In some ways, it is a pity that iterators are compiled away and there is no metadata that reflects the original intent. Without it, we are always going to dependent on our knowledge of the compiler's implementation. For example, we have noticed that the Async CTP changes the way that iterators are code generated, so we'll have to do some more work to support that. However, with that warning in place, we seem to do a reasonable job of decompiling the iterators that are built into the framework. Hopefully, the EAP will give us a chance to find examples where we don't spot the pattern correctly or regenerate the wrong code, and we can improve things. Please give it a go, and report any problems.

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• How I Work: Staying Productive Whilst Traveling

  - by BuckWoody

  I travel a lot. Not like some folks that are gone every week, mind you, although in the last month I’ve been to: Cambridge, UK; Anchorage, AK; San Jose, CA; Copenhagen, DK, Boston, MA; and I’m currently en-route to Anaheim, CA.  While this many places in a month is a bit unusual for me, I would say I travel frequently. I’ve travelled most of my 28+ years in IT, and at one time was a consultant traveling weekly.   With that much time away from my primary work location, I have to find ways to stay productive. Some might say “just rest – take a nap!” – but I’m not able to do that. For one thing, I’m a very light sleeper and I’ve never slept on a plane - even a 30+ hour trip to New Zealand in Business Class - so that just isn’t option. I also am not always in the plane, of course. There’s the hotel, the taxi/bus/train, the airport and then all that over again when I arrive. Since my regular jobs have many demands, I have to get work done.   Note: No, I’m not always focused on work. I need downtime just like everyone else. Sometimes I just think, watch a movie or listen to tunes – and I give myself permission to do that anytime – sometimes the whole trip. I have too fewheartbeats left in life to only focus on work – it’s just not that important, and neither am I. Some of these tasks are letters to friends and family, or other personal things. What I’m talking about here is a plan, not some task list I have to follow. When I get to the location I’m traveling to, I always build in as much time as I can to ensure I enjoy those sights and the people I’m with. I would find traveling to be a waste if not for that.   The Unrealistic Expectation As I would evaluate the trip I was taking – say a 6-8 hour flight – I would expect to get 10-12 hours of work done. After all, there’s the time at the airport, the taxi and so on, and then of course the time in the air with all of the room, power, internet and everything else I needed to get my work done. I would pile up tasks at home, pack my bags, and head happily to the magical land of the TSA.   Right. On return from the trip, I had accomplished little, had more e-mails and other work that had piled up, and I was tired, hungry, and unorganized. This had to change. So, I decided to do three things: Segment my work Set realistic expectations Plan accordingly  Segmenting By Available Resources The first task was to decide what kind of work I could do in each location – if any. I found that I was dependent on a few things to get work done, such as power, the Internet, and a place to sit down. Before I fly, I take some time at home to get all of the work I’d like to accomplish while away segmented into these areas, and print that out on paper, which goes in my suit-coat pocket along with a mechanical pencil. I print my tickets, and I’m all set for the adventure ahead. Then I simply do each kind of work whenever I’m in that situation. No power There are certain times when I don’t have power available. But not only that, I might not even be able to use most of my electronics. So I now schedule as many phone calls as I can for the taxi/bus/train ride and the airports as I can. I have a paper notebook (Moleskine, of course) and a pencil and I print out any notes or numbers I need prior to the trip. Once I’m airborne or at the airport, I work on my laptop. I check and respond to e-mails, create slides, write code, do architecture, whatever I can.  If I can’t use any electronics, or once the power runs out, I schedule time for reading. I can read at the airport or anywhere, actually, even in-flight or any other transport. I “read with a pencil”, meaning I take a lot of notes, which I liketo put in OneNote, but since in most cases I don’t have power, I use the Moleskine to do that. Speaking of which, sometimes as I’m thinking I come up with new topics, ideas, blog posts, or things to teach in my classes. Once again I take out the notebook and write it down. All of these notes get a check-mark when I get back to the office and transfer the writing to OneNote. I’ve tried those “smart pens” and so on to automate this, but it just never works out. Pencil and paper are just fine. As I mentioned, sometime I just need to think. I’ll do nothing, and let my mind wander, thinking of nothing in particular, or some math problem or science question I’m interested in. My only issue with this is that I communicate tothink, and I don’t want to drive people crazy by being that guy that won’t shut up, so I think in a different way. Power, but no Internet or Phone If I have power but no Internet or phone, I focus on the laptop and the tablet as before, and I also recharge my other gadgets. Power, Internet, Phone and a Place to Work At first I thought that when I arrived at the hotel or event I could get the same amount of work done that I do at the office. Not so. There’s simply too many distractions, things you need, or other issues that allow this. Of course, Ican work on any device, read, think, write or whatever, but I am simply not as productive as I am in my home office. So I plan for about 25-50% as much work getting done in this environment as I think I could really do. I’ve done some measurements, and this holds out to be true almost every time. The key is that I re-set my expectations (and my co-worker’s expectations as well) that this is the case. I use the Out-Of-Office notices to let people know that I’m just not going to be 100% at this time – it’s hard for everyone, but it’s more honest and realistic, and I’d rather they know that – and that I realize that – than to let them think I’m totally available. Because I’m not – I’m traveling. I don’t tend to put too much detail, because after all I don’t necessarily want to let people know when I’m not home :) but I do think it’s important to let people that depend on my know that I’ll get back with them later. I hope this helps you think through your own methodology of staying productive when you travel. Or perhaps you just go offline, and don’t worry about any of this – good for you! That’s completely valid as well.   (Oh, and yes, I wrote this at 35K feet, on Alaska Airlines on a trip. :)  Practice what you preach, Buck.)

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• DBA Best Practices - A Blog Series: Episode 1 - Backups

  - by Argenis

    This blog post is part of the DBA Best Practices series, on which various topics of concern for daily database operations are discussed. Your feedback and comments are very much welcome, so please drop by the comments section and be sure to leave your thoughts on the subject. Morning Coffee When I was a DBA, the first thing I did when I sat down at my desk at work was checking that all backups had completed successfully. It really was more of a ritual, since I had a dual system in place to check for backup completion: 1) the scheduled agent jobs to back up the databases were set to alert the NOC in failure, and 2) I had a script run from a central server every so often to check for any backup failures. Why the redundancy, you might ask. Well, for one I was once bitten by the fact that database mail doesn't work 100% of the time. Potential causes for failure include issues on the SMTP box that relays your server email, firewall problems, DNS issues, etc. And so to be sure that my backups completed fine, I needed to rely on a mechanism other than having the servers do the taking - I needed to interrogate the servers and ask each one if an issue had occurred. This is why I had a script run every so often. Some of you might have monitoring tools in place like Microsoft System Center Operations Manager (SCOM) or similar 3rd party products that would track all these things for you. But at that moment, we had no resort but to write our own Powershell scripts to do it. Now it goes without saying that if you don't have backups in place, you might as well find another career. Your most sacred job as a DBA is to protect the data from a disaster, and only properly safeguarded backups can offer you peace of mind here. "But, we have a cluster...we don't need backups" Sadly I've heard this line more than I would have liked to. You need to understand that a cluster is comprised of shared storage, and that is precisely your single point of failure. A cluster will protect you from an issue at the Operating System level, and also under an outage of any SQL-related service or dependent devices. But it will most definitely NOT protect you against corruption, nor will it protect you against somebody deleting data from a table - accidentally or otherwise. Backup, fine. How often do I take a backup? The answer to this is something you will hear frequently when working with databases: it depends. What does it depend on? For one, you need to understand how much data your business is willing to lose. This is what's called Recovery Point Objective, or RPO. If you don't know how much data your business is willing to lose, you need to have an honest and realistic conversation about data loss expectations with your customers, internal or external. From my experience, their first answer to the question "how much data loss can you withstand?" will be "zero". In that case, you will need to explain how zero data loss is very difficult and very costly to achieve, even in today's computing environments. Do you want to go ahead and take full backups of all your databases every hour, or even every day? Probably not, because of the impact that taking a full backup can have on a system. That's what differential and transaction log backups are for. Have I answered the question of how often to take a backup? No, and I did that on purpose. You need to think about how much time you have to recover from any event that requires you to restore your databases. This is what's called Recovery Time Objective. Again, if you go ask your customer how long of an outage they can withstand, at first you will get a completely unrealistic number - and that will be your starting point for discussing a solution that is cost effective. The point that I'm trying to get across is that you need to have a plan. This plan needs to be practiced, and tested. Like a football playbook, you need to rehearse the moves you'll perform when the time comes. How often is up to you, and the objective is that you feel better about yourself and the steps you need to follow when emergency strikes. A backup is nothing more than an untested restore Backups are files. Files are prone to corruption. Put those two together and realize how you feel about those backups sitting on that network drive. When was the last time you restored any of those? Restoring your backups on another box - that, by the way, doesn't have to match the specs of your production server - will give you two things: 1) peace of mind, because now you know that your backups are good and 2) a place to offload your consistency checks with DBCC CHECKDB or any of the other DBCC commands like CHECKTABLE or CHECKCATALOG. This is a great strategy for VLDBs that cannot withstand the additional load created by the consistency checks. If you choose to offload your consistency checks to another server though, be sure to run DBCC CHECKDB WITH PHYSICALONLY on the production server, and if you're using SQL Server 2008 R2 SP1 CU4 and above, be sure to enable traceflags 2562 and/or 2549, which will speed up the PHYSICALONLY checks further - you can read more about this enhancement here. Back to the "How Often" question for a second. If you have the disk, and the network latency, and the system resources to do so, why not backup the transaction log often? As in, every 5 minutes, or even less than that? There's not much downside to doing it, as you will have to clear the log with a backup sooner than later, lest you risk running out space on your tlog, or even your drive. The one drawback to this approach is that you will have more files to deal with at restore time, and processing each file will add a bit of extra time to the entire process. But it might be worth that time knowing that you minimized the amount of data lost. Again, test your plan to make sure that it matches your particular needs. Where to back up to? Network share? Locally? SAN volume? This is another topic where everybody has a favorite choice. So, I'll stick to mentioning what I like to do and what I consider to be the best practice in this regard. I like to backup to a SAN volume, i.e., a drive that actually lives in the SAN, and can be easily attached to another server in a pinch, saving you valuable time - you wouldn't need to restore files on the network (slow) or pull out drives out a dead server (been there, done that, it’s also slow!). The key is to have a copy of those backup files made quickly, and, if at all possible, to a remote target on a different datacenter - or even the cloud. There are plenty of solutions out there that can help you put such a solution together. That right there is the first step towards a practical Disaster Recovery plan. But there's much more to DR, and that's material for a different blog post in this series.

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• DBA Best Practices - A Blog Series: Episode 1 - Backups

  - by Argenis

    This blog post is part of the DBA Best Practices series, on which various topics of concern for daily database operations are discussed. Your feedback and comments are very much welcome, so please drop by the comments section and be sure to leave your thoughts on the subject. Morning Coffee When I was a DBA, the first thing I did when I sat down at my desk at work was checking that all backups have completed successfully. It really was more of a ritual, since I had a dual system in place to check for backup completion: 1) the scheduled agent jobs to back up the databases were set to alert the NOC in failure, and 2) I had a script run from a central server every so often to check for any backup failures. Why the redundancy, you might ask. Well, for one I was once bitten by the fact that database mail doesn't work 100% of the time. Potential causes for failure include issues on the SMTP box that relays your server email, firewall problems, DNS issues, etc. And so to be sure that my backups completed fine, I needed to rely on a mechanism other than having the servers do the taking - I needed to interrogate the servers and ask each one if an issue had occurred. This is why I had a script run every so often. Some of you might have monitoring tools in place like Microsoft System Center Operations Manager (SCOM) or similar 3rd party products that would track all these things for you. But at that moment, we had no resort but to write our own Powershell scripts to do it. Now it goes without saying that if you don't have backups in place, you might as well find another career. Your most sacred job as a DBA is to protect the data from a disaster, and only properly safeguarded backups can offer you peace of mind here. "But, we have a cluster...we don't need backups" Sadly I've heard this line more than I would have liked to. You need to understand that a cluster is comprised of shared storage, and that is precisely your single point of failure. A cluster will protect you from an issue at the Operating System level, and also under an outage of any SQL-related service or dependent devices. But it will most definitely NOT protect you against corruption, nor will it protect you against somebody deleting data from a table - accidentally or otherwise. Backup, fine. How often do I take a backup? The answer to this is something you will hear frequently when working with databases: it depends. What does it depend on? For one, you need to understand how much data your business is willing to lose. This is what's called Recovery Point Objective, or RPO. If you don't know how much data your business is willing to lose, you need to have an honest and realistic conversation about data loss expectations with your customers, internal or external. From my experience, their first answer to the question "how much data loss can you withstand?" will be "zero". In that case, you will need to explain how zero data loss is very difficult and very costly to achieve, even in today's computing environments. Do you want to go ahead and take full backups of all your databases every hour, or even every day? Probably not, because of the impact that taking a full backup can have on a system. That's what differential and transaction log backups are for. Have I answered the question of how often to take a backup? No, and I did that on purpose. You need to think about how much time you have to recover from any event that requires you to restore your databases. This is what's called Recovery Time Objective. Again, if you go ask your customer how long of an outage they can withstand, at first you will get a completely unrealistic number - and that will be your starting point for discussing a solution that is cost effective. The point that I'm trying to get across is that you need to have a plan. This plan needs to be practiced, and tested. Like a football playbook, you need to rehearse the moves you'll perform when the time comes. How often is up to you, and the objective is that you feel better about yourself and the steps you need to follow when emergency strikes. A backup is nothing more than an untested restore Backups are files. Files are prone to corruption. Put those two together and realize how you feel about those backups sitting on that network drive. When was the last time you restored any of those? Restoring your backups on another box - that, by the way, doesn't have to match the specs of your production server - will give you two things: 1) peace of mind, because now you know that your backups are good and 2) a place to offload your consistency checks with DBCC CHECKDB or any of the other DBCC commands like CHECKTABLE or CHECKCATALOG. This is a great strategy for VLDBs that cannot withstand the additional load created by the consistency checks. If you choose to offload your consistency checks to another server though, be sure to run DBCC CHECKDB WITH PHYSICALONLY on the production server, and if you're using SQL Server 2008 R2 SP1 CU4 and above, be sure to enable traceflags 2562 and/or 2549, which will speed up the PHYSICALONLY checks further - you can read more about this enhancement here. Back to the "How Often" question for a second. If you have the disk, and the network latency, and the system resources to do so, why not backup the transaction log often? As in, every 5 minutes, or even less than that? There's not much downside to doing it, as you will have to clear the log with a backup sooner than later, lest you risk running out space on your tlog, or even your drive. The one drawback to this approach is that you will have more files to deal with at restore time, and processing each file will add a bit of extra time to the entire process. But it might be worth that time knowing that you minimized the amount of data lost. Again, test your plan to make sure that it matches your particular needs. Where to back up to? Network share? Locally? SAN volume? This is another topic where everybody has a favorite choice. So, I'll stick to mentioning what I like to do and what I consider to be the best practice in this regard. I like to backup to a SAN volume, i.e., a drive that actually lives in the SAN, and can be easily attached to another server in a pinch, saving you valuable time - you wouldn't need to restore files on the network (slow) or pull out drives out a dead server (been there, done that, it’s also slow!). The key is to have a copy of those backup files made quickly, and, if at all possible, to a remote target on a different datacenter - or even the cloud. There are plenty of solutions out there that can help you put such a solution together. That right there is the first step towards a practical Disaster Recovery plan. But there's much more to DR, and that's material for a different blog post in this series.

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• Recursion in the form of a Recursive Func&lt;T, T&gt;

  - by ToStringTheory

  I gotta admit, I am kind of surprised that I didn’t realize I could do this sooner.  I recently had a problem which required a recursive function call to come up with the answer.  After some time messing around with a recursive method, and creating an API that I was not happy with, I was able to create an API that I enjoy, and seems intuitive. Introduction To bring it to a simple example, consider the summation to n: A mathematically identical formula is: In a .NET function, this can be represented by a function: Func<int, int> summation = x => x*(x+1)/2 Calling summation with an input integer will yield the summation to that number: var sum10 = summation(4); //sum10 would be equal to 10 But what if I wanted to get a second level summation…  First some to n, and then use that argument as the input to the same function, to find the second level summation: So as an easy example, calculate the summation to 3, which yields 6.  Then calculate the summation to 6 which yields 21. Represented as a mathematical formula - So what if I wanted to represent this as .NET functions.  I can always do: //using the summation formula from above var sum3 = summation(3); //sets sum3 to 6 var sum3_2 = summation(sum3); //sets sum3 to 21 I could always create a while loop to perform the calculations too: Func<int, int> summation = x => x*(x+1)/2; //for the interests of a smaller example, using shorthand int sumResultTo = 3; int level = 2; while(level-- > 0) { sumResultTo = summation(sumResultTo); } //sumResultTo is equal to 21 now. Or express it as a for-loop, method calls, etc…  I really didn’t like any of the options that I tried.  Then it dawned on me – since I was using a Func<T, T> anyways, why not use the Func’s output from one call as the input as another directly. Some Code So, I decided that I wanted a recursion class.  Something that I would be generic and reusable in case I ever wanted to do something like this again. It is limited to only the Func<T1, T2> level of Func, and T1 must be the same as T2. The first thing in this class is a private field for the function: private readonly Func<T, T> _functionToRecurse; So, I since I want the function to be unchangeable, I have defined it as readonly.  Therefore my constructor looks like: public Recursion(Func<T, T> functionToRecurse) { if (functionToRecurse == null) { throw new ArgumentNullException("functionToRecurse", "The function to recurse can not be null"); } _functionToRecurse = functionToRecurse; } Simple enough.  If you have any questions, feel free to post them in the comments, and I will be sure to answer them. Next, I want enough. If be able to get the result of a function dependent on how many levels of recursion: private Func<T, T> GetXLevel(int level) { if (level < 1) { throw new ArgumentOutOfRangeException("level", level, "The level of recursion must be greater than 0"); } if (level == 1) return _functionToRecurse; return _GetXLevel(level - 1, _functionToRecurse); } So, if you pass in 1 for the level, you get just the Func<T,T> back.  If you say that you want to go deeper down the rabbit hole, it calls a method which accepts the level it is at, and the function which it needs to use to recurse further: private Func<T, T> _GetXLevel(int level, Func<T, T> prevFunc) { if (level == 1) return y => prevFunc(_functionToRecurse(y)); return _GetXLevel(level - 1, y => prevFunc(_functionToRecurse(y))); } That is really all that is needed for this class. If I exposed the GetXLevel function publicly, I could use that to get the function for a level, and pass in the argument..  But I wanted something better.  So, I used the ‘this’ array operator for the class: public Func<T,T> this[int level] { get { if (level < 1) { throw new ArgumentOutOfRangeException("level", level, "The level of recursion must be greater than 0"); } return this.GetXLevel(level); } } So, using the same example above of finding the second recursion of the summation of 3: var summator = new Recursion<int>(x => (x * (x + 1)) / 2); var sum_3_level2 = summator[2](3); //yields 21 You can even find just store the delegate to the second level summation, and use it multiple times: var summator = new Recursion<int>(x => (x * (x + 1)) / 2); var sum_level2 = summator[2]; var sum_3_level2 = sum_level2(3); //yields 21 var sum_4_level2 = sum_level2(4); //yields 55 var sum_5_level2 = sum_level2(5); //yields 120 Full Code Don’t think I was just going to hold off on the full file together and make you do the hard work…  Copy this into a new class file: public class Recursion<T> { private readonly Func<T, T> _functionToRecurse; public Recursion(Func<T, T> functionToRecurse) { if (functionToRecurse == null) { throw new ArgumentNullException("functionToRecurse", "The function to recurse can not be null"); } _functionToRecurse = functionToRecurse; } public Func<T,T> this[int level] { get { if (level < 1) { throw new ArgumentOutOfRangeException("level", level, "The level of recursion must be greater than 0"); } return this.GetXLevel(level); } } private Func<T, T> GetXLevel(int level) { if (level < 1) { throw new ArgumentOutOfRangeException("level", level, "The level of recursion must be greater than 0"); } if (level == 1) return _functionToRecurse; return _GetXLevel(level - 1, _functionToRecurse); } private Func<T, T> _GetXLevel(int level, Func<T, T> prevFunc) { if (level == 1) return y => prevFunc(_functionToRecurse(y)); return _GetXLevel(level - 1, y => prevFunc(_functionToRecurse(y))); } } Conclusion The great thing about this class, is that it can be used with any function with same input/output parameters.  I strived to find an implementation that I found clean and useful, and I finally settled on this.  If you have feedback – good or bad, I would love to hear it!

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• "Service Unavailable" when browsing to static HTML page in non-application IIS website on Windows 2003 (possibly SharePoint WSS 2.0 related?)

  - by Jordan Rieger

  Background: My client has an old Pentium III Windows 2003 server whose 16/36 GB disks are dying. On it he has a database-driven web site and email application that needs further customization by a developer (me). First we need to get it working on the new server. The original developer is no longer available to provide a system setup guide. So my client got a tech who imaged the old drives over to the new server and managed to get it booting. But the IIS-driven site no longer works. In fact it seems that IIS itself does not work. Problem: Service Unavailable when attempting to browse from the server itself to the URL for a local Web Site called test which I setup in IIS to serve a single static index.htm file. This I did to isolate the problem, and eliminate the client's application from the equation. The site is setup on port 80 with the host header "test.myclientsdomain.com", and I used the etc\hosts file to point that host at the local IP. I know the host entry took effect because I can ping it. When doing an iisreset, I get: Attempting start... Restart attempt failed. IIS Admin Service or a service dependent on IIS Admin is not active. It most likely failed to start, which may mean that it's disabled. Despite this message, the services all stay in the Started state. The only relevant System event logs I found are: Event Type: Error Event Source: W3SVC Event Category: None Event ID: 1002 Date: 11/4/2012 Time: 11:04:47 PM User: N/A Computer: ALPHA1 Description: Application pool 'DefaultAppPool' is being automatically disabled due to a series of failures in the process(es) serving that application pool. Event Type: Error Event Source: W3SVC Event Category: None Event ID: 1039 Date: 11/4/2012 Time: 11:13:12 PM User: N/A Computer: ALPHA1 Description: A process serving application pool 'DefaultAppPool' reported a failure. The process id was '5636'. The data field contains the error number. Data: 0000: 7e 00 07 80 ~.. And one Application event log: Event Type: Error Event Source: Windows SharePoint Services 2.0 Event Category: None Event ID: 1000 Date: 11/4/2012 Time: 11:34:04 PM User: N/A Computer: ALPHA1 Description: #50070: Unable to connect to the database STS_Config on ALPHA2\SharePoint. Check the database connection information and make sure that the database server is running. That last log tells me that the tech may have initially tried to have both the old and the new server running, by renaming the new server from ALPHA1 to ALPHA2. And perhaps SharePoint grabbed onto that change, and now can't tell that the machine name has been switched back to the old ALPHA1. But why would SharePoint interfere with a static IIS web site serving a single HTML file? The test site is not even within an Application pool (I clicked the Remove button.) What I have tried/eliminated: No relevant services seem to be disabled: IIS Admin, WWW Publishing, Sharepoint Timer Giving Full Control to All Users/Everyone on the c:\inetpub\test folder serving my test site. I can connect to and query the local SharePoint config database (ALPHA1\SHAREPOINT\STS_CONFIG) from SSMS. But when I try to do stsadm -o setconfigdb -connect -databaseserver ALPHA1\SHAREPOINT it tells me The SharePoint admininstration port does not exist. Please use stsadm.exe to create it. And when I do that, using the port 9487 specified in the IIS SharePoint Admin site config, it tells me the port is already in use. Needless to say, simply browsing to the admin site gives me a similar error about being unable to reach the config database. I didn't want to go further down the SharePoint path as it may be completed unrelated to my IIS issue, and I don't even know yet if SharePoint is required for this application to work. The app itself is ASP.Net/C#/Silverlight and a little MS Word integration (maybe that's where the SharePoint stuff comes in.)

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• x11vnc working in Ubuntu 10.10

  - by pablorc

  I'm trying to start x11vnc in a Ubuntu 10.10 (my server is in Amazon EC2), but I have the next error $ sudo x11vnc -forever -usepw -httpdir /usr/share/vnc-java/ -httpport 5900 -auth /usr/sbin/gdm 25/11/2010 13:29:51 passing arg to libvncserver: -httpport 25/11/2010 13:29:51 passing arg to libvncserver: 5900 25/11/2010 13:29:51 -usepw: found /home/ubuntu/.vnc/passwd 25/11/2010 13:29:51 x11vnc version: 0.9.10 lastmod: 2010-04-28 pid: 3504 25/11/2010 13:29:51 XOpenDisplay(":0.0") failed. 25/11/2010 13:29:51 Trying again with XAUTHLOCALHOSTNAME=localhost ... 25/11/2010 13:29:51 *************************************** 25/11/2010 13:29:51 *** XOpenDisplay failed (:0.0) *** x11vnc was unable to open the X DISPLAY: ":0.0", it cannot continue. *** There may be "Xlib:" error messages above with details about the failure. Some tips and guidelines: ** An X server (the one you wish to view) must be running before x11vnc is started: x11vnc does not start the X server. (however, see the -create option if that is what you really want). ** You must use -display <disp>, -OR- set and export your $DISPLAY environment variable to refer to the display of the desired X server. - Usually the display is simply ":0" (in fact x11vnc uses this if you forget to specify it), but in some multi-user situations it could be ":1", ":2", or even ":137". Ask your administrator or a guru if you are having difficulty determining what your X DISPLAY is. ** Next, you need to have sufficient permissions (Xauthority) to connect to the X DISPLAY. Here are some Tips: - Often, you just need to run x11vnc as the user logged into the X session. So make sure to be that user when you type x11vnc. - Being root is usually not enough because the incorrect MIT-MAGIC-COOKIE file may be accessed. The cookie file contains the secret key that allows x11vnc to connect to the desired X DISPLAY. - You can explicitly indicate which MIT-MAGIC-COOKIE file should be used by the -auth option, e.g.: x11vnc -auth /home/someuser/.Xauthority -display :0 x11vnc -auth /tmp/.gdmzndVlR -display :0 you must have read permission for the auth file. See also '-auth guess' and '-findauth' discussed below. ** If NO ONE is logged into an X session yet, but there is a greeter login program like "gdm", "kdm", "xdm", or "dtlogin" running, you will need to find and use the raw display manager MIT-MAGIC-COOKIE file. Some examples for various display managers: gdm: -auth /var/gdm/:0.Xauth -auth /var/lib/gdm/:0.Xauth kdm: -auth /var/lib/kdm/A:0-crWk72 -auth /var/run/xauth/A:0-crWk72 xdm: -auth /var/lib/xdm/authdir/authfiles/A:0-XQvaJk dtlogin: -auth /var/dt/A:0-UgaaXa Sometimes the command "ps wwwwaux | grep auth" can reveal the file location. Starting with x11vnc 0.9.9 you can have it try to guess by using: -auth guess (see also the x11vnc -findauth option.) Only root will have read permission for the file, and so x11vnc must be run as root (or copy it). The random characters in the filenames will of course change and the directory the cookie file resides in is system dependent. See also: http://www.karlrunge.com/x11vnc/faq.html I've already tried with some -auth options but the error persist. I have gdm running. Thank you in advance

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• squid3 auth thru samba using ntlm to AD doesn't work

  - by derty

  some users here are spending to much time exploring the WWW. So big boss whats to get this under control. We use a squid3 just for some security reason and chace benefits. and now i'm trying to set up a new proxy on a different server (Debian 6) Permissions are defined in AC and the squid3 should get the auth thru samba/winbind by using the ntlm protocol. but i'll get all the time Access, denited. it only works by using LDAP but thats not the way i need it. here some log and confs squid access.log 1326878095.784 1 192.168.15.27 TCP_DENIED/407 4049 GET http://at.msn.com/? -NONE/- text/html 1326878095.791 1 192.168.15.27 TCP_DENIED/407 4294 GET http://at.msn.com/? - NONE/- text/html 1326878095.803 9 192.168.15.27 TCP_DENIED/403 4028 GET http://at.msn.com/? kavan NONE/- text/html 1326878095.848 0 192.168.15.27 TCP_DENIED/403 3881 GET http://www.squid-cache.org/Artwork/SN.png kavan NONE/- text/html 1326878100.279 0 192.168.15.27 TCP_DENIED/403 3735 GET http://www.google.at/ kavan NONE/- text/html 1326878100.296 0 192.168.15.27 TCP_DENIED/403 3870 GET http://www.squid-cache.org/Artwork/SN.png kavan NONE/- text/html 1326878155.700 0 192.168.15.27 TCP_DENIED/407 4072 GET http://ie9cvlist.ie.microsoft.com/IE9CompatViewList.xml - NONE/- text/html 1326878155.705 2 192.168.15.27 TCP_DENIED/407 4317 GET http://ie9cvlist.ie.microsoft.com/IE9CompatViewList.xml - NONE/- text/html 1326878155.709 3 192.168.15.27 TCP_DENIED/403 4026 GET http://ie9cvlist.ie.microsoft.com/IE9CompatViewList.xml kavan NONE/- text/html squid chace 2012/01/18 10:12:49| Creating Swap Directories 2012/01/18 10:12:49| Starting Squid Cache version 3.1.6 for x86_64-pc-linux-gnu... 2012/01/18 10:12:49| Process ID 17236 2012/01/18 10:12:49| With 65535 file descriptors available 2012/01/18 10:12:49| Initializing IP Cache... 2012/01/18 10:12:49| DNS Socket created at [::], FD 7 2012/01/18 10:12:49| DNS Socket created at 0.0.0.0, FD 8 2012/01/18 10:12:49| Adding nameserver 192.168.15.2 from /etc/resolv.conf 2012/01/18 10:12:49| Adding nameserver 192.168.15.19 from /etc/resolv.conf 2012/01/18 10:12:49| Adding nameserver 192.168.15.1 from /etc/resolv.conf 2012/01/18 10:12:49| Adding domain schoenbrunn.local from /etc/resolv.conf 2012/01/18 10:12:49| helperOpenServers: Starting 5/5 'squid_ldap_auth' processes 2012/01/18 10:12:49| helperOpenServers: Starting 10/10 'ntlm_auth' processes 2012/01/18 10:12:49| helperOpenServers: Starting 10/10 'squid_kerb_auth' processes 2012/01/18 10:12:49| squid_kerb_auth: INFO: Starting version 1.0.5 2012/01/18 10:12:49| squid_kerb_auth: INFO: Starting version 1.0.5 2012/01/18 10:12:49| squid_kerb_auth: INFO: Starting version 1.0.5 2012/01/18 10:12:49| squid_kerb_auth: INFO: Starting version 1.0.5 2012/01/18 10:12:49| squid_kerb_auth: INFO: Starting version 1.0.5 2012/01/18 10:12:49| squid_kerb_auth: INFO: Starting version 1.0.5 2012/01/18 10:12:49| squid_kerb_auth: INFO: Starting version 1.0.5 2012/01/18 10:12:49| squid_kerb_auth: INFO: Starting version 1.0.5 2012/01/18 10:12:49| helperOpenServers: Starting 5/5 'squid_ldap_group' processes 2012/01/18 10:12:49| squid_kerb_auth: INFO: Starting version 1.0.5 2012/01/18 10:12:49| squid_kerb_auth: INFO: Starting version 1.0.5 2012/01/18 10:12:49| Unlinkd pipe opened on FD 73 2012/01/18 10:12:49| Local cache digest enabled; rebuild/rewrite every 3600/3600 sec 2012/01/18 10:12:49| Store logging disabled 2012/01/18 10:12:49| Swap maxSize 0 + 262144 KB, estimated 20164 objects 2012/01/18 10:12:49| Target number of buckets: 1008 2012/01/18 10:12:49| Using 8192 Store buckets 2012/01/18 10:12:49| Max Mem size: 262144 KB 2012/01/18 10:12:49| Max Swap size: 0 KB 2012/01/18 10:12:49| Using Least Load store dir selection 2012/01/18 10:12:49| Set Current Directory to /var/spool/squid3 2012/01/18 10:12:49| Loaded Icons. 2012/01/18 10:12:49| Accepting HTTP connections at [::]:3128, FD 74. 2012/01/18 10:12:49| HTCP Disabled. 2012/01/18 10:12:49| Squid modules loaded: 0 2012/01/18 10:12:49| Adaptation support is off. 2012/01/18 10:12:49| Ready to serve requests. 2012/01/18 10:12:50| storeLateRelease: released 0 objects smb.conf # Domain Authntication Settings workgroup = <WORKGROUP> security = ads password server = <DOMAINNAME>.LOCAL realm = <DOMAINNAME>.LOCAL ldap ssl = no # logging log level = 5 max log size = 50 # logs split per machine log file = /var/log/samba/%m.log # max 50KB per log file, then rotate ; max log size = 50 # User settings username map = /etc/samba/smbusers idmap uid = 10000-20000000 idmap gid = 10000-20000000 idmap backend = ad ; template primary group = <ad group> template shell = /sbin/nologin # Winbind Settings winbind separator = + winbind enum users = Yes winbind enum groups = Yes winbind netsted groups = Yes winbind nested groups = Yes winbind cache time = 10 winbind use default domain = Yes #Other Globals unix charset = LOCALE server string = <SERVERNAME> load printers = no printing = cups cups options = raw ; printcap name = /etc/printcap #obtain list of printers automatically on SystemV ; printcap name = lpstat ; printing = cups squid.conf auth_param ntlm program /usr/bin/ntlm_auth --require-membership-of=<DOMAINNAME>\\INTERNETZ --helper-protocol=squid-2.5-ntlmssp auth_param ntlm children 10 auth_param basic program /usr/lib/squid3/squid_ldap_auth -R -b "dc=<dcname>,dc=local" -D "cn=administrator,cn=Users,dc=<domainname>,dc=local" -w "******" -f sAMAccountName=%s -h 192.168.15.19:3268 auth_param basic realm "Proxy Authentifizierung. Bitte geben Sie Ihren Benutzername und Ihr Passwort ein!" #means insert you PW in an other language - # external_acl_type InetGroup %LOGIN /usr/lib/squid3/squid_ldap_group -R -b "dc=<domainname>,dc=local" -D "cn=administrator,cn=Users,dc=<domainname>,dc=local" -w "******" -f "(&(objectclass=person)(sAMAccountName=%v) (memberof=cn=%a,cn=internetz,dc=<domainname>,dc=local))" -h 192.168.15.19:3268 auth_param negotiate program /usr/lib/squid3/squid_kerb_auth -d auth_param negotiate children 10 auth_param negotiate keep_alive on acl localnet proxy_auth REQUIRED acl InetAccess external InetGroup Internetz http_access allow InetAccess http_access deny all acl auth proxy_auth REQUIRED http_access allow auth and a very suspicious is that by adding the proxy server to the Domain i see 2 new entries in the PC one with the original computer-name leopoldine and one with leopoldine CNF:f8efa4c4-ff0e-4217-939d-f1523b43464d ?!? I tried a lot, really... but i stuck on this problem... i actually i even reinstalled all dependent programs and reconfigured them from default. Group exists and has me in it. Firefox running on the old proxy and i use IE for testing the new one. But i'll get all the time Access-Denited and to be honest i'm quite a beginner, so please don't be to prude. I'll interested in improving, i'll get the information we need to fix this but i started working 2 month ago and got only 1 1/2 year's training and not a single sec. in linux ;)

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• Best Method to SFTP or FTPS Files via SSIS

  - by Registered User

  What is the best method using SSIS (SQL Server Integration Services) to upload a file to either a remote SFTP (secure FTP with SSH2 protocal) or FTPS (FTP over SSL) site? I've used the following methods, but each has short-comings I would like to avoid: COZYROC LIBRARY Method: Install the CozyRoc library on each development and production server and use the SFTP task to upload the files. Pros: Easy to use. It looks, smells, and feels like a normal SSIS task. SSIS also recognizes the password as sensitive information and allows you all the normal options for protecting the sensitive information instead of just storing it in clear text in a non-secure manner. Works well with other SSIS tasks such as ForEach Loop Containers. Errors out when uploads and downloads fail. Works well when you don't know the names of the files on the remote FTP site to download or when you won't know the name of the file to upload until run-time. Cons: Costs money to license in a production environment. Makes you dependent upon the vendor to update their libraries between each version. Although they already have a 2008 version, this caused me a problem during the CTP's of 2008. Requires installing the libraries on each development and production machine. COMMAND LINE SFTP PROGRAM Method: Install a free command-line SFTP application such as Putty and execute it either by running a batch file or operating system process task. Pros: Free, free, and free. You can be sure it is secure if you are using Putty since numerous GUI FTP clients appear to use Putty under the covers. You DEFINATELY know you are using SSH2 and not SSH. Cons: The two command-line utilities I tried (Putty and Cygwin) required storing the SFTP password in a non-secure location. I haven't found a good way to capture failures or errors when uploading files. The process doesn't look and smell like SSIS. Most of the code is encapsulated in text files instead of SSIS itself. Difficult to use if you don't know the exact name of the file you are uploading or downloading. A 3RD PARTY C# or VB.NET LIBRARY Method: Install a SFTP or FTPS library and use a Script Task that references the library to upload the files. (I've never tried this, so I'm going to guess at the pros and cons) Pros: Probably easy to capture errors. Should work well with variables, so it would probably be easy to use even when you don't know the exact name of the file you are uploading or downloading. Cons: It's a script task combined with .NET libraries. If you are using SSIS, then you probably are more comfortable with SSIS tasks then .NET code. Script tasks are also difficult to troubleshoot since they don't have the same debugging tools and features as regular .NET projects. Creates a dependency on 3rd party code that may not work between different versions of SQL Server. To be fair, it is probably MORE likely to work between different versions of SQL Server than a 3rd party SSIS task library. Another huge con -- I haven't found a free C# or VB.NET library that does this as of yet. So if anyone knows of one, then please let me know!

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• Bug Triage

  In this blog post brain dump, I'll attempt to describe the process my team tries to follow when dealing with new bug reports (specifically, code defect reports). This is not official Microsoft policy, just the way we do things… if you do things differently and want to share, you can do so at the bottom in the comments (or on your blog).Feature Triage TeamA subset of the feature crew, the triage team (which has representations from the PM, Dev and QA disciplines), looks at all unassigned bugs at regular intervals. This can be weekly or daily (or other frequency) dependent on which part of the product cycle we are in and what the untriaged bug load looks like. They discuss each bug considering the evidence and make a decision of whether the bug goes from Not Yet Assigned to Assigned (plus the name of the DEV to fix this) or whether it goes from Active to Resolved (which means it gets assigned back to the requestor for closure or further debate if they were not present at the triage meeting). Close to critical milestones, the feature triage team needs to further justify bugs they take to additional higher-level triage teams.Bug Opened = Not Yet AssignedSomeone (typically an SDET from the QA team) creates the bug item (e.g. in TFS), ensuring they populate all the relevant fields including: Title, Description, Repro Steps (including the Actual Result at the end of the steps), attachments of code and/or screenshots, Build number that they observed the issue in, regression details if applicable, how it was found, if a test case exists or needs to be created etc. They also indicate their opinion on the Priority and Severity. The bug status is left as Not Yet Assigned."Issue" versus "Fix for issue"The solution to some bugs is easy to determine, e.g. "bug: the column name is misspelled". Obviously the fix is to correct the spelling – still, the triage team should be explicit and enter the correct spelling in the bug's Description. Note that a bad bug name here would be "bug: fix the spelling of the column" (it describes the solution, rather than the problem).Other solutions are trickier to establish, e.g. "bug: the column header is not accessible (can only be clicked on with the mouse, not reached via keyboard)". What is the correct solution here? The last thing to do is leave this undetermined and just assign it to a developer. The solution has to be entered in the description. Behind this type of a bug usually hides a spec defect or a new feature request.The person opening the bug should focus on describing the issue, rather than the solution. The person indicates what the fix is in their opinion by stating the Expected Result (immediately after stating the Actual Result). If they have a complex suggested solution, that should be split out in a separate part, but the triage team has the final say before assigning it. If the solution is lengthy/complicated to describe, the bug can be assigned to the PM. Note: the strict interpretation suggests that any bug with no clear, obvious solution is always a hole in the spec and should always go to the PM. This also ensures the spec gets updated.Not Yet Assigned - Not Yet Assigned (on someone else's plate)If the bug is observed in our feature, but the cause is actually another team, we change the Area Path (which is the way we identify teams in TFS) and leave it as Not Yet Assigned. The triage team may add more comments as appropriate including potentially changing the repro steps. In some cases, we may even resolve the bug in our area path and open a new bug in the area path of the other team.Even though there is no action on a dev on the team, the bug still needs to be tracked. One way of doing this is to implement some notification system that informs the team when the tracked bug changed status; another way is to occasionally run a global query (against all area paths) for bugs that have been opened by a member of the team and follow up with the current owners for stale bugs.Not Yet Assigned - ResolvedThis state transition can only be made by the Feature Triage Team.0. Sometimes the bug description is not clear and in that case it gets Resolved as More Information Needed, so the original requestor can provide it.After understanding what the bug item is about, the first decision is to determine whether it needs to go to a dev.1. If it is a known bug, it gets resolved as "Duplicate" and linked to the existing bug.2. If it is "By Design" it gets resolved as such, indicating that the triage team does not think this is a bug.3. If the bug does not repro on latest bits, it is resolved as "No Repro"4. The most painful: If it is decided that we cannot fix it for this release it gets resolved as "Postponed" or "Won't Fix". The former is typically due to resources and time constraints, while the latter is due to deciding that it is not important enough to consume our resources in any release (yes, not all bugs must be fixed!). For both cases, there are other factors that contribute to the decision such as: existence of a reasonable workaround, frequency we expect users to encounter the issue, dependencies on other team to offer a solution, whether it breaks a core scenario, whether it prohibits customer feedback on a major feature, is it a regression from a previous release, impact of the fix on other partner teams (e.g. User Education, User Experience, Localization/Globalization), whether this is the right fix, does the fix impact performance goals, and last but not least, severity of bug (e.g. loss of customer data, security threat, crash, hang). The bar for fixing a bug goes up as the release date approaches. The triage team becomes hardnosed about which bugs to take, while the developers are busy resolving assigned bugs thus everyone drives for Zero Bug Bounce (ZBB). ZBB is when you have 0 active bugs older than 48 hours.Not Yet Assigned - AssignedIf the bug is something we decide to fix in this release and the solution is known, then it is assigned to a DEV. This is either the developer that will do the work, or a Lead that can further assign it to one of his developer team based on a load balancing algorithm of their choosing.Sometimes, the triage team needs the dev to do some investigation work before deciding whether to take the fix; similarly, the checkin for the fix may be gated on code review by the triage team. In these cases, these instructions are provided in the comments section of the bug and when the developer is done they notify the triage team for final decision.Additionally, a Priority and Severity (from 0 to 4) has to be entered, e.g. a P0 means "drop anything you are doing and fix this now" whereas a P4 is something you get to after all P0,1,2,3 bugs are fixed.From a testing perspective, if the bug was found through ad-hoc testing or an external team, the decision is made whether test cases should be added to avoid future regressions. This is communicated to the QA team.Assigned - ResolvedWhen the developer receives the bug (they should be checking daily for new bugs on their plate looking at bugs in order of priority and from older to newer) they can send it back to triage if the information is not clear. Otherwise, they investigate the bug, setting the Sub Status to "Investigating"; if they cannot make progress, they set the Sub Status to "Blocked" and discuss this with triage or whoever else can help them get unblocked. Once they are unblocked, they set the Sub Status to "Working on Solution"; once they are code complete they send a code review request, setting the Sub Status to "Fix Available". After the iterative code review process is over and everyone is happy with the fix, the developer checks it in and changes the state of the bug from Active (and Assigned to them) to Resolved (and Assigned to someone else).The developer needs to ensure that when the status is changed to Resolved that it is assigned to a QA person. For example, maybe the PM opened the bug, but it should be a QA person that will verify the fix - the developer needs to manually change the assignee in that case. Typically the QA person will send an email to the original requestor notifying them that the fix is verified.Resolved - ??In all cases above, note that the final state was Resolved. What happens after that? The final step should be Closed. The bug is closed once the QA person verifying the fix is happy with it. If the person is not happy, then they change the state from Resolved to Active, thus sending it back to the developer. If the developer and QA person cannot reach agreement, then triage can be brought into it. An easy way to do that is change the status back to Not Yet Assigned with appropriate comments so the triage team can re-review.It is important to note that only QA can close a bug. That means that if the opener of the bug was a PM, when the bug gets resolved by the dev it may land on the PM's plate and after a quick review, the PM would re-assign to an SDET, which is the only role that can close bugs. One exception to this is if the person that filed the bug is external: in that case, we leave it Resolved and assigned to them and also send them a notification that they need to verify the fix. Another exception is if specialized developer knowledge is needed for verifying the bug fix (e.g. it was a refactoring suggestion bug typically not observable by the user) in which case it is fine to have a developer verify the fix, and ideally a different developer to the one that opened the bug.Other links on bug triageA quick search reveals that others have talked about this subject, e.g. here, here, here, here and here.Your take?If you have other best practices your team uses to deal with incoming bug reports, feel free to share in the comments below or on your blog. Comments about this post welcome at the original blog.

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• Parallelism in .NET – Part 2, Simple Imperative Data Parallelism

  - by Reed

  In my discussion of Decomposition of the problem space, I mentioned that Data Decomposition is often the simplest abstraction to use when trying to parallelize a routine.  If a problem can be decomposed based off the data, we will often want to use what MSDN refers to as Data Parallelism as our strategy for implementing our routine.  The Task Parallel Library in .NET 4 makes implementing Data Parallelism, for most cases, very simple. Data Parallelism is the main technique we use to parallelize a routine which can be decomposed based off data.  Data Parallelism refers to taking a single collection of data, and having a single operation be performed concurrently on elements in the collection.  One side note here: Data Parallelism is also sometimes referred to as the Loop Parallelism Pattern or Loop-level Parallelism.  In general, for this series, I will try to use the terminology used in the MSDN Documentation for the Task Parallel Library.  This should make it easier to investigate these topics in more detail. Once we’ve determined we have a problem that, potentially, can be decomposed based on data, implementation using Data Parallelism in the TPL is quite simple.  Let’s take our example from the Data Decomposition discussion – a simple contrast stretching filter.  Here, we have a collection of data (pixels), and we need to run a simple operation on each element of the pixel.  Once we know the minimum and maximum values, we most likely would have some simple code like the following: for (int row=0; row < pixelData.GetUpperBound(0); ++row) { for (int col=0; col < pixelData.GetUpperBound(1); ++col) { pixelData[row, col] = AdjustContrast(pixelData[row, col], minPixel, maxPixel); } } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } This simple routine loops through a two dimensional array of pixelData, and calls the AdjustContrast routine on each pixel. As I mentioned, when you’re decomposing a problem space, most iteration statements are potentially candidates for data decomposition.  Here, we’re using two for loops – one looping through rows in the image, and a second nested loop iterating through the columns.  We then perform one, independent operation on each element based on those loop positions. This is a prime candidate – we have no shared data, no dependencies on anything but the pixel which we want to change.  Since we’re using a for loop, we can easily parallelize this using the Parallel.For method in the TPL: Parallel.For(0, pixelData.GetUpperBound(0), row => { for (int col=0; col < pixelData.GetUpperBound(1); ++col) { pixelData[row, col] = AdjustContrast(pixelData[row, col], minPixel, maxPixel); } }); Here, by simply changing our first for loop to a call to Parallel.For, we can parallelize this portion of our routine.  Parallel.For works, as do many methods in the TPL, by creating a delegate and using it as an argument to a method.  In this case, our for loop iteration block becomes a delegate creating via a lambda expression.  This lets you write code that, superficially, looks similar to the familiar for loop, but functions quite differently at runtime. We could easily do this to our second for loop as well, but that may not be a good idea.  There is a balance to be struck when writing parallel code.  We want to have enough work items to keep all of our processors busy, but the more we partition our data, the more overhead we introduce.  In this case, we have an image of data – most likely hundreds of pixels in both dimensions.  By just parallelizing our first loop, each row of pixels can be run as a single task.  With hundreds of rows of data, we are providing fine enough granularity to keep all of our processors busy. If we parallelize both loops, we’re potentially creating millions of independent tasks.  This introduces extra overhead with no extra gain, and will actually reduce our overall performance.  This leads to my first guideline when writing parallel code: Partition your problem into enough tasks to keep each processor busy throughout the operation, but not more than necessary to keep each processor busy. Also note that I parallelized the outer loop.  I could have just as easily partitioned the inner loop.  However, partitioning the inner loop would have led to many more discrete work items, each with a smaller amount of work (operate on one pixel instead of one row of pixels).  My second guideline when writing parallel code reflects this: Partition your problem in a way to place the most work possible into each task. This typically means, in practice, that you will want to parallelize the routine at the “highest” point possible in the routine, typically the outermost loop.  If you’re looking at parallelizing methods which call other methods, you’ll want to try to partition your work high up in the stack – as you get into lower level methods, the performance impact of parallelizing your routines may not overcome the overhead introduced. Parallel.For works great for situations where we know the number of elements we’re going to process in advance.  If we’re iterating through an IList<T> or an array, this is a typical approach.  However, there are other iteration statements common in C#.  In many situations, we’ll use foreach instead of a for loop.  This can be more understandable and easier to read, but also has the advantage of working with collections which only implement IEnumerable<T>, where we do not know the number of elements involved in advance. As an example, lets take the following situation.  Say we have a collection of Customers, and we want to iterate through each customer, check some information about the customer, and if a certain case is met, send an email to the customer and update our instance to reflect this change.  Normally, this might look something like: foreach(var customer in customers) { // Run some process that takes some time... DateTime lastContact = theStore.GetLastContact(customer); TimeSpan timeSinceContact = DateTime.Now - lastContact; // If it's been more than two weeks, send an email, and update... if (timeSinceContact.Days > 14) { theStore.EmailCustomer(customer); customer.LastEmailContact = DateTime.Now; } } Here, we’re doing a fair amount of work for each customer in our collection, but we don’t know how many customers exist.  If we assume that theStore.GetLastContact(customer) and theStore.EmailCustomer(customer) are both side-effect free, thread safe operations, we could parallelize this using Parallel.ForEach: Parallel.ForEach(customers, customer => { // Run some process that takes some time... DateTime lastContact = theStore.GetLastContact(customer); TimeSpan timeSinceContact = DateTime.Now - lastContact; // If it's been more than two weeks, send an email, and update... if (timeSinceContact.Days > 14) { theStore.EmailCustomer(customer); customer.LastEmailContact = DateTime.Now; } }); Just like Parallel.For, we rework our loop into a method call accepting a delegate created via a lambda expression.  This keeps our new code very similar to our original iteration statement, however, this will now execute in parallel.  The same guidelines apply with Parallel.ForEach as with Parallel.For. The other iteration statements, do and while, do not have direct equivalents in the Task Parallel Library.  These, however, are very easy to implement using Parallel.ForEach and the yield keyword. Most applications can benefit from implementing some form of Data Parallelism.  Iterating through collections and performing “work” is a very common pattern in nearly every application.  When the problem can be decomposed by data, we often can parallelize the workload by merely changing foreach statements to Parallel.ForEach method calls, and for loops to Parallel.For method calls.  Any time your program operates on a collection, and does a set of work on each item in the collection where that work is not dependent on other information, you very likely have an opportunity to parallelize your routine.

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• Visual Studio 2010 Extension Manager (and the new VS 2010 PowerCommands Extension)

  - by ScottGu

  This is the twenty-third in a series of blog posts I’m doing on the VS 2010 and .NET 4 release. Today’s blog post covers some of the extensibility improvements made in VS 2010 – as well as a cool new "PowerCommands for Visual Studio 2010” extension that Microsoft just released (and which can be downloaded and used for free). [In addition to blogging, I am also now using Twitter for quick updates and to share links. Follow me at: twitter.com/scottgu] Extensibility in VS 2010 VS 2010 provides a much richer extensibility model than previous releases.  Anyone can build extensions that add, customize, and light-up the Visual Studio 2010 IDE, Code Editors, Project System and associated Designers. VS 2010 Extensions can be created using the new MEF (Managed Extensibility Framework) which is built-into .NET 4.  You can learn more about how to create VS 2010 extensions from this this blog post from the Visual Studio Team Blog. VS 2010 Extension Manager Developers building extensions can distribute them on their own (via their own web-sites or by selling them).  Visual Studio 2010 also now includes a built-in “Extension Manager” within the IDE that makes it much easier for developers to find, download, and enable extensions online.  You can launch the “Extension Manager” by selecting the Tools->Extension Manager menu option: This loads an “Extension Manager” dialog which accesses an “online gallery” at Microsoft, and then populates a list of available extensions that you can optionally download and enable within your copy of Visual Studio: There are already hundreds of cool extensions populated within the online gallery.  You can browse them by category (use the tree-view on the top-left to filter them).  Clicking “download” on any of the extensions will download, install, and enable it. PowerCommands for Visual Studio 2010 This weekend Microsoft released the free PowerCommands for Visual Studio 2010 extension to the online gallery.  You can learn more about it here, and download and install it via the “Extension Manager” above (search for PowerCommands to find it). The PowerCommands download adds dozens of useful commands to Visual Studio 2010.  Below is a screen-shot of just a few of the useful commands that it adds to the Solution Explorer context menus: Below is a list of all the commands included with this weekend’s PowerCommands for Visual Studio 2010 release: Enable/Disable PowerCommands in Options dialog This feature allows you to select which commands to enable in the Visual Studio IDE. Point to the Tools menu, then click Options. Expand the PowerCommands options, then click Commands. Check the commands you would like to enable. Note: All power commands are initially defaulted Enabled. Format document on save / Remove and Sort Usings on save The Format document on save option formats the tabs, spaces, and so on of the document being saved. It is equivalent to pointing to the Edit menu, clicking Advanced, and then clicking Format Document. The Remove and sort usings option removes unused using statements and sorts the remaining using statements in the document being saved. Note: The Remove and sort usings option is only available for C# documents. Format document on save and Remove and sort usings both are initially defaulted OFF. Clear All Panes This command clears all output panes. It can be executed from the button on the toolbar of the Output window. Copy Path This command copies the full path of the currently selected item to the clipboard. It can be executed by right-clicking one of these nodes in the Solution Explorer: The solution node; A project node; Any project item node; Any folder. Email CodeSnippet To email the lines of text you select in the code editor, right-click anywhere in the editor and then click Email CodeSnippet. Insert Guid Attribute This command adds a Guid attribute to a selected class. From the code editor, right-click anywhere within the class definition, then click Insert Guid Attribute. Show All Files This command shows the hidden files in all projects displayed in the Solution Explorer when the solution node is selected. It enhances the Show All Files button, which normally shows only the hidden files in the selected project node. Undo Close This command reopens a closed document , returning the cursor to its last position. To reopen the most recently closed document, point to the Edit menu, then click Undo Close. Alternately, you can use the CtrlShiftZ shortcut. To reopen any other recently closed document, point to the View menu, click Other Windows, and then click Undo Close Window. The Undo Close window appears, typically next to the Output window. Double-click any document in the list to reopen it. Collapse Projects This command collapses a project or projects in the Solution Explorer starting from the root selected node. Collapsing a project can increase the readability of the solution. This command can be executed from three different places: solution, solution folders and project nodes respectively. Copy Class This command copies a selected class entire content to the clipboard, renaming the class. This command is normally followed by a Paste Class command, which renames the class to avoid a compilation error. It can be executed from a single project item or a project item with dependent sub items. Paste Class This command pastes a class entire content from the clipboard, renaming the class to avoid a compilation error. This command is normally preceded by a Copy Class command. It can be executed from a project or folder node. Copy References This command copies a reference or set of references to the clipboard. It can be executed from the references node, a single reference node or set of reference nodes. Paste References This command pastes a reference or set of references from the clipboard. It can be executed from different places depending on the type of project. For CSharp projects it can be executed from the references node. For Visual Basic and Website projects it can be executed from the project node. Copy As Project Reference This command copies a project as a project reference to the clipboard. It can be executed from a project node. Edit Project File This command opens the MSBuild project file for a selected project inside Visual Studio. It combines the existing Unload Project and Edit Project commands. Open Containing Folder This command opens a Windows Explorer window pointing to the physical path of a selected item. It can be executed from a project item node Open Command Prompt This command opens a Visual Studio command prompt pointing to the physical path of a selected item. It can be executed from four different places: solution, project, folder and project item nodes respectively. Unload Projects This command unloads all projects in a solution. This can be useful in MSBuild scenarios when multiple projects are being edited. This command can be executed from the solution node. Reload Projects This command reloads all unloaded projects in a solution. It can be executed from the solution node. Remove and Sort Usings This command removes and sort using statements for all classes given a project. It is useful, for example, in removing or organizing the using statements generated by a wizard. This command can be executed from a solution node or a single project node. Extract Constant This command creates a constant definition statement for a selected text. Extracting a constant effectively names a literal value, which can improve readability. This command can be executed from the code editor by right-clicking selected text. Clear Recent File List This command clears the Visual Studio recent file list. The Clear Recent File List command brings up a Clear File dialog which allows any or all recent files to be selected. Clear Recent Project List This command clears the Visual Studio recent project list. The Clear Recent Project List command brings up a Clear File dialog which allows any or all recent projects to be selected. Transform Templates This command executes a custom tool with associated text templates items. It can be executed from a DSL project node or a DSL folder node. Close All This command closes all documents. It can be executed from a document tab. How to temporarily disable extensions Extensions provide a great way to make Visual Studio even more powerful, and can help improve your overall productivity.  One thing to keep in mind, though, is that extensions run within the Visual Studio process (DevEnv.exe) and so a bug within an extension can impact both the stability and performance of Visual Studio.  If you ever run into a situation where things seem slower than they should, or if you crash repeatedly, please temporarily disable any installed extensions and see if that fixes the problem.  You can do this for extensions that were installed via the online gallery by re-running the extension manager (using the Tools->Extension Manager menu option) and by selecting the “Installed Extensions” node on the top-left of the dialog – and then by clicking “Disable” on any of the extensions within your installed list: Hope this helps, Scott

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• AuthSub token from Google/YouTube API is always returned as invalid

  - by Miriam Raphael Roberts

  Anyone out there have experience with the YouTube/Google API? I am trying to login to Google/Youtube using clientLogin, retrieve an AuthSub token, exchange it for a multi-session token and then use it in our upload form. Just a note that we are not going to have other users logging into our (secure) website, this is for our use only (no multi-users). We just want a way to upload videos to our YT account via our own website without having to login/upload to YouTube. Ultimately, everything is dependent on the first step. My AuthSub token is always being returned as invalid (Error '403'). All the steps I used are below with username/password changed. Anyone have an insight on why my AuthSub is always invalid? I am spending an enormous amount of time trying to get this to work. STEP 1: Getting the authsub token from Youtube/Google POST /youtube/accounts/ClientLogin HTTP/1.1 User-Agent: curl/7.10.6 (i386-redhat-linux-gnu) libcurl/7.10.6 OpenSSL/0.9.7a ipv6 zlib/1.1.4 Host: www.google.com Pragma: no-cache Accept: image/gif, image/x-xbitmap, image/jpeg, image/pjpeg, */* Content-Type:application/x-www-form-urlencoded Content-Length: 86 Email=MyGoogleUsername&Passwd=MyGooglePasswd&accountType=GOOGLE&service=youtube&source=Test RESPONSE RECEIVED: Auth=AIwbFAR99f3iACfkT-5PXCB-1tN4vlyP_1CiNZ8JOn6P-......yv4d4zeGRemNm4il1e-M6czgfDXAR0w9fQ YouTubeUser=MyYouTubeUsername CURL COMMAND USED: /usr/bin/curl -S -v --location https://www.google.com/youtube/accounts/ClientLogin --data Email=MyGoogleUsername&Passwd=MyGooglePasswd&accountType=GOOGLE&service=youtube&source=Test --header Content-Type:application/x-www-form-urlencoded STEP 2: Exchanging the AuthSub token for a multi-use token GET /accounts/AuthSubSessionToken HTTP/1.1 User-Agent: curl/7.10.6 (i386-redhat-linux-gnu) libcurl/7.10.6 OpenSSL/0.9.7a ipv6 zlib/1.1.4 Host: www.google.com Pragma: no-cache Accept: image/gif, image/x-xbitmap, image/jpeg, image/pjpeg, */* Content-Type:application/x-www-form-urlencoded Authorization: AuthSub token="AIwbFASiRR3XDKs......p5Oy_VA_9U2yV1enxJoVGSgMlZqTcjKw9mS861vlc9GWTH9D9sQ" Response received: 403 Invalid AuthSub token. curl command used: /usr/bin/curl -S -v --location https://www.google.com/accounts/AuthSubSessionToken --header Content-Type:application/x-www-form-urlencoded -H Authorization: AuthSub token="AIwbFAQR_4xG2g.....vp3BQZW5XEMyIj_wFozHSTEQ-BQRfYuIY-1CyqLeQ" STEP 3: Checking to see if the token is good/valid GET /accounts/AuthSubTokenInfo HTTP/1.1 User-Agent: curl/7.10.6 (i386-redhat-linux-gnu) libcurl/7.10.6 OpenSSL/0.9.7a ipv6 zlib/1.1.4 Host: www.google.com Pragma: no-cache Accept: image/gif, image/x-xbitmap, image/jpeg, image/pjpeg, */* Content-Type:application/x-www-form-urlencoded Authorization: AuthSub token="AIwbFASiRR3XDKsNkaIoPaujN5RQhKs3u.....A_9U2yV1enxJoVGSgMlZqTcjKw9mS861vlc9GWTH9D9sQ" Received response: 403 Invalid AuthSub token. curl command used: /usr/bin/curl -S -v --location https://www.google.com/accounts/AuthSubTokenInfo --header Content-Type:application/x-www-form-urlencoded -H Authorization: AuthSub token="AIwbFAQR_4xG2gHoAKDsNdFqdZdwWjGeNquOLpvp3BQZW5XEMyIj_wFozHSTEQ-BQRfYuIY-1CyqLeQ" STEP 4: Trying to get the upload token using the authsub token POST /action/GetUploadToken HTTP/1.1 User-Agent: curl/7.10.6 (i386-redhat-linux-gnu) libcurl/7.10.6 OpenSSL/0.9.7a ipv6 zlib/1.1.4 Host: gdata.youtube.com Pragma: no-cache Accept: image/gif, image/x-xbitmap, image/jpeg, image/pjpeg, */* Content-Type:application/atom+xml Authorization: AuthSub token="AIwbFASiRR3XDKsNkaIoPaujN5RQhp5Oy_VA_9U2yV1enxJoVGSgMlZqTcjKw9mS861vlc9GWTH9D9sQ" X-Gdata-Key:key="AI39si5EQyo-TZPFAnmGjxJGFKpxd_7a6hEERh_3......R82AShoQ" Content-Length:0 GData-Version:2 Recevied Response: 401 Token invalid - Invalid AuthSub token. Curl command used: /usr/bin/curl -S -v --location http://gdata.youtube.com/action/GetUploadToken -H Content-Type:application/atom+xml -H Authorization: AuthSub token="AIwbFASiRR3XDKs....sYDp5Oy_VA_9U2yV1enxJoVGSgMlZqTcjKw9mS861vlc9GWTH9D9sQ" -H X-Gdata-Key:key="AI39si5EQyo-TZPFAnmGjxJGF......Kpxd6dN2J1oHFQYTj_7a6hEERh_3E48R82AShoQ" -H Content-Length:0 -H GData-Version:2

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