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• What's New In 11.1.2.1 (Talleyrand SP1)

  - by russ.bishop

  This release is primarily about bug fixes and that's what we spent the most time on, but we also addressed a number of other things: 1. Performance improvements We've done a lot of work to improve the performance of page load and execution times. For example, the View Compare page is about half the size it was previously! We've also done a lot of work on the server to improve performance of queries, exports, action scripts, etc. We implemented some finer-grained locking so fewer operations will block other users while they are in progress. We made some optimizations to improve performance when you have a lot of network or database latency as well. Just a few examples: An Import that previously took 8 GB of memory and hours to complete now runs in about 30 minutes and never takes more than 1 GB of RAM. Searching by exact Node Name now completes within 2 seconds even for a hierarchy with millions of nodes. Another search that was taking 30 seconds to run now completes in less than 5 seconds. 2. Upgrade support This release supports automatic upgrade from previous releases, built right into the console. 3. Console Improvements The Console has been reorganized and made easier to use. It is also much more multi-threaded so it responds quicker without freezing up when you save changes or when it needs to get status. 4. Property Namespaces Properties now have a concept called a Namespace. This is tied into the Application Templates to prevent conflicts with duplicate property names. Right now, if you have an AccountType and you pull in the HFM template, it also has AccountType so you end up creating properties with decorations on the name like "Account Type (HFM)". This is no longer necessary. In addition, properties within a namespace must have unique labels but they can be duplicated across namespaces. So in the Property Grid when you click on the HFM category, you just see "AccountType". When you click on MyCategory, you see "AccountType", but they are different properties with different values. Within formulas, the names are still unique (eg: Custom.AccountType vs HFM.AccountType). I'll write more about this one later. 5. Single Sign On DRM now supports Single Sign-On via HSS. For example, if you are using Oracle's OAM as your SSO solution then you configure HSS to use OAM just like you would before. You also configure DRM to use HSS, again just like before. Then you configure OAM to protect the DRM web app, like you would any other website. However once you do those things, users are no longer prompted to enter their username/password. They simply get redirected to OAM if they don't already have a login token, otherwise they pick their application and sail right into DRM. You can also avoid having to pick an application (see the next item) 6. URL-based navigation You can now specify the application you want to log into via the URL. Combined with SSO and your Intranet, it becomes easy to provide links on our intranet portal that take users directly into a specific DRM application. We also support specifying the Version, Hierarchy, and Node. Again, this can be used on your internal portal, but the scenarios get even more interesting when you are using workflow like Oracle BPEL you can automatically generate links within emails that will take users directly to a specific node in the UI. 7. Job status and cancellation A lot of the jobs now report their status and support true cancellation. Action Scripts also report a progress complete percentage since the amount of work is known ahead of time. 8. Action Script Options Action scripts support Option declarations at the top of the file so a script can self-describe (when specified in the file, the corresponding item in the file is ignored). For example: Option|DetectDelimiter Option|UsePropertyNames|true This will tell DRM to automatically detect the delimiter (a pipe symbol in this case) and that all references to properties are by Name, not by Label. Note that when you load a script in the UI, if you use Labels we automatically try to match them up if they are unique. Any duplicates are indicated and you are presented with a choice to pick which property you actually referred to. This is somewhat similar to Version substitution, but tailored for properties. There are other more minor changes and like I said earlier a lot of bug fixes and performance improvements. Hopefully I will get a chance to dig into some of these things in future blog posts.

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• A little primer on using TFS with a small team

  - by johndoucette

  The scenario; A small team of 3 developers mostly in maintenance mode with traditional ASP.net, classic ASP, .Net integration services and utilities with the company’s third party packages, and a bunch of java-based Coldfusion web applications all under Visual Source Safe (VSS). They are about to embark on a huge SharePoint 2010 new construction project and wanted to use subversion instead VSS. TFS was a foreign word and smelled of “high cost” and of an “over complicated process”. Since they had no preconditions about the old TFS versions (‘05 & ‘08), it was fun explaining how simple it was to install a TFS server and get the ball rolling, with or without all the heavy stuff one sometimes associates with such a huge and powerful application management lifecycle product. So, how does a small team begin using TFS? 1. Start by using source control and migrate current VSS source trees into TFS. You can take the latest version or migrate the entire version history. It’s up to you on whether you want a clean start or need quick access to all the version notes and history of the bits. 2. Since most shops are mainly in maintenance mode with existing applications, begin using bug workitems for everything. When you receive an issue/bug from your current tracking system, manually enter the workitem in TFS right through Visual Studio. You can automate the integration to the current tracking system later or replace it entirely. Believe me, this thing is powerful and can handle even the largest of help desks. 3. With new construction, begin work with requirements and task workitems and follow the traditional sprint-based development lifecycle. Obviously, some minor training will be needed, but don’t fear, this is very intuitive and MSDN has a ton of lesson based labs and videos. 4. For the java developers, use the new Team Explorer Everywhere 2010 plugin (recently known as Teamprise). There is a seamless interface in Eclipse, but also a good command-line utility for other environments such as Dreamweaver. 5. Wait to fully integrate the whole workitem/project management/testing process until your team is familiar with the integrated workitems for bugs and code. After a while, you will see the team wanting more transparency into the work they are all doing and naturally, everyone will want workitems to help them organize the chaos! 6. Management will be limited in the value of the reports until you have a fully blown implementation of project planning, construction, build, deployment and testing. However, there are some basic “bug rate” reports and current backlog listings that can provide good information. Some notable explanations of TFS; Work Item Tracking and Project Management - A workitem represents the unit of work within the system which enables tracking of all activities produced by a user, whether it is a developer, business user, project manager or tester. The properties of a workitem such as linked changesets (checked-in code), who updated the data and when, the states and reasons for change, are all transitioned to a data warehouse within TFS for reporting purposes. A workitem can be defines as a "bug", "requirement", test case", or a "change request". They drive the work effort by the individual assigned to it and also provide a key role in defining what needs to be done. Workitems are the things the team needs to do to accomplish a goal. Test Case Management - Starting with a workitem known as a "test case", a tester (or developer) can now author and manage test cases within a formal test plan subsystem. Although TFS supports the test case workitem type, there is a new product known as the VS Test Professional 2010 which allows a tester to facilitate manual tests including fast forwarding steps in the process to arrive at the assertion point quickly. This repeatable process provides quick regression tests and can be conducted by the business user to ensure completeness during UAT. In addition, developers no longer can provide a response to a bug with the line "cannot reproduce". With every test run, attachments including the recorded session, captured environment configurations and settings, screen shots, intellitrace (debugging history), and in some cases if the lab manager is being used, a snapshot of the tested environment is available. Version Control - A modern system allowing shared check-in/check-out, excellent merge conflict resolution, Shelvesets (personal check-ins), branching/merging visualization, public workspaces, gated check-ins, security hierarchy capabilities, and changeset/workitem tracking. Knowing what was done with the code by any developer has become much easier to picture and resolve issues. Team Build - Automate the compilation process whether you need it to be whenever a developer checks-in code, periodically such as nightly builds for testers in the morning, or manual builds to be deployed into production. Each build can run through pre-determined tests, perform code analysis to see if the developer conforms to the team standards, and reject the build if either fails. Project Portal & Reporting - Provide management with a dashboard with insight into the project(s). "Where are we" in each step of the way including past iterations and the current burndown rate. Enabling this feature is easy as it seamlessly interfaces with existing SharePoint implementations.

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• How to Customize Fonts and Colors for Gnome Panels in Ubuntu Linux

  - by The Geek

  Earlier this week we showed you how to make the Gnome Panels totally transparent, but you really need some customized fonts and colors to make the effect work better. Here’s how to do it. This article is the first part of a multi-part series on how to customize the Ubuntu desktop, written by How-To Geek reader and ubergeek, Omar Hafiz. Changing the Gnome Colors the Easy Way You’ll first need to install Gnome Color Chooser which is available in the default repositories (the package name is gnome-color-chooser). Then go to System > Preferences > Gnome Color Chooser to launch the program. When you see all these tabs you immediately know that Gnome Color Chooser does not only change the font color of the panel, but also the color of the fonts all over Ubuntu, desktop icons, and many other things as well. Now switch to the panel tab, here you can control every thing about your panels. You can change font, font color, background and background color of the panels and start menus. Tick the “Normal” option and choose the color you want for the panel font. If you want you can change the hover color of the buttons on the panel by too. A little below the color option is the font options, this includes the font, font size, and the X and Y positioning of the font. The first two options are pretty straight forward, they change the typeface and the size. The X-Padding and Y-Padding may confuse you but they are interesting, they may give a nice look for your panels by increasing the space between items on your panel like this: X-Padding:   Y-Padding:   The bottom half of the window controls the look of your start menus which is the Applications, Places, and Systems menus. You can customize them just the way you did with the panel.   Alright, this was the easy way to change the font of your panels. Changing the Gnome Theme Colors the Command-Line Way The other hard (not so hard really) way will be changing the configuration files that tell your panel how it should look like. In your Home Folder, press Ctrl+H to show the hidden files, now find the file “.gtkrc-2.0”, open it and insert this line in it. If there are any other lines in the file leave them intact. include “/home/<username>/.gnome2/panel-fontrc” Don’t forget to replace the <user_name> with you user account name. When done close and save the file. Now navigate the folder “.gnome2” from your Home Folder and create a new file and name it “panel-fontrc”. Open the file you just created with a text editor and paste the following in it: style “my_color”{fg[NORMAL] = “#FF0000”}widget “*PanelWidget*” style “my_color”widget “*PanelApplet*” style “my_color” This text will make the font red. If you want other colors you’ll need to replace the Hex value/HTML Notation (in this case #FF0000) with the value of the color you want. To get the hex value you can use GIMP, Gcolor2 witch is available in the default repositories or you can right-click on your panel > Properties > Background tab then click to choose the color you want and copy the Hex value. Don’t change any other thing in the text. When done, save and close. Now press Alt+F2 and enter “killall gnome-panel” to force it to restart or you can log out and login again. Most of you will prefer the first way of changing the font and color for it’s ease of applying and because it gives you much more options but, some may not have the ability/will to download and install a new program on their machine or have reasons of their own for not to using it, that’s why we provided the two way. Latest Features How-To Geek ETC How to Enable User-Specific Wireless Networks in Windows 7 How to Use Google Chrome as Your Default PDF Reader (the Easy Way) How To Remove People and Objects From Photographs In Photoshop Ask How-To Geek: How Can I Monitor My Bandwidth Usage? Internet Explorer 9 RC Now Available: Here’s the Most Interesting New Stuff Here’s a Super Simple Trick to Defeating Fake Anti-Virus Malware The Splendiferous Array of Culinary Tools [Infographic] Add a Real-Time Earth Wallpaper App to Ubuntu with xplanetFX The Citroen GT – An Awesome Video Game Car Brought to Life [Video] Final Man vs. Machine Round of Jeopardy Unfolds; Watson Dominates Give Chromium-Based Browser Desktop Notifications a Native System Look in Ubuntu Chrome Time Track Is a Simple Task Time Tracker

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• Adding a DLL to the GAC in Windows 7

  - by Jim Giercyk

  I recently created a DLL and I wanted to reference it from a project I was developing in Visual Studio.  In previous versions of Windows, doing so was simply a matter of dropping the DLL file in the C:\Windows\assembly folder.  That would add the DLL to the Global Assembly Cache (GAC) and make it accessible in Visual Studio.  However, as is often the case, Window 7 is different.  Even if you have Administrator privileges on your machine, you still do not have permission to drop a file in the assembly folder.  Undaunted, I thought about using the old DOS command line utility gacutil.exe.  Microsoft developed the tool as part of the .Net framework, and it is available in the Windows SDK Framework Tools.  If you have never used gacutil.exe before, you can find out everything you ever wanted to know but were afraid to ask here: http://msdn.microsoft.com/en-us/library/ex0ss12c(v=vs.80).aspx .  Unfortunately, if you do not have the Windows SDK loaded on your development machine, you will need to install it to use gacutil, but it is relatively quick and painless, and the framework tools are very useful.  Look here for your latest SDK: http://www.microsoft.com/download/en/search.aspx?q=Windows%20SDK .   After installing the SDK, I tried installing my DLL to the GAC by running gacutil from a DOS command line: That’s odd.  Microsoft is shipping a tool that cannot be executed even with Administrator rights?  Let me stop here and say that I am by no means a Windows security expert, so I actually did contact my system administrators, and they were not sure how to fix the problem….there must be a super administrator access level, but it isn’t available to your average developer in my company.  The solution outlined here is working within the boundaries of a normal windows Administrator. So, now the hacker in me bubbles to the surface.  What if I were to create a simple BAT file containing the gacutil command?  It’s so crazy it just might work!  Ugh!  I was starting to think this would never work, but then I realized that simply executing a batch program did not change my level of access.  Typically in Windows 7, you would select the “Run As Administrator” option to temporarily act as an administrator for the purpose of executing a process.  However, that option is not available for BAT files run from the command line.  SOLUTION: Create a desktop shortcut to execute the BAT file, which in turn will execute the line command…..are you still with me?  I created a shortcut and pointed it to my batch file.  Theoretically, all I need to do now is right-click on the shortcut and select “Run As Administrator” and we’re good, right?  Well, kinda.  If you notice the syntax of my BAT file, the name of the DLL is passed in as a parameter.  Therefore, I either have to hard-code the file name in the BAT program (YUCK!!), or I can leave the parameter and drag the DLL file to the shortcut and drop it.  Sweet, drag-and-drop works for me…..but if I use the drag-and-drop method, there is no way for me to right-click and select “Run As Administrator”.  That is not a problem…..I simply have to adjust the properties of the shortcut I created and I am in business.  I Right-clicked on the shortcut and select “Properties”.  Under the “Shortcut” tab there is an “Advanced” button…..I clicked it. All I needed to do was check the “Run As Administrator” box: In summary, what I have done is create a BAT file to execute a command line utility, gacutil.exe.  Then, rather than executing the BAT file from the command line, I created a desktop shortcut to run it and set the shortcut properties to “Run As Administrator”.  This will effectively mean I am executing the command line utility with Administrator privileges.  Pretty sneaky. Now, when I drag the DLL file  over to the shortcut, it starts the BAT file and adds the DLL to the assembly cache.  I created another BAT file to remove a DLL from the GAC in case the need should arise.  The code for that is: Give it a try.  I can’t imagine why updating the GAC has been made into such a chore in Windows 7.  Hopefully there is a service pack in the works that will give developers the functionality they had in Windows XP, but in the meantime, this workaround is extremely useful.

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• PASS: 2013 Summit Location

  - by Bill Graziano

  HQ recently posted a brief update on our search for a location for 2013.  It includes links to posts by four Board members and two community members. I’d like to add my thoughts to the mix and ask you a question.  But I can’t give you a real understanding without telling you some history first. So far we’ve had the Summit in Chicago, San Francisco, Orlando, Dallas, Denver and Seattle.  Each has a little different feel and distinct memories.  I enjoyed getting drinks by the pool in Orlando after the sessions ended.  I didn’t like that our location in Dallas was so far away from all the nightlife.  Denver was in downtown but we had real challenges with hotels.  I enjoyed the different locations.  I always enjoyed the announcement during the third keynote with the location of the next Summit. There are two big events that impacted my thinking on the Summit location.  The first was our transition to the new management company in early 2007.  The event that September in Denver was put on with a six month planning cycle by a brand new headquarters staff.  It wasn’t perfect but came off much better than I had dared to hope.  It also moved us out of the cookie cutter conferences that we used to do into a model where we have a lot more control.  I think you’ll all agree that the production values of our last few Summits have been fantastic.  That Summit also led to our changing relationship with Microsoft.  Microsoft holds two seats on the PASS Board.  All the PASS Board members face the same challenge: we all have full-time jobs and PASS comes in second place professionally (or sometimes further back).  Starting in 2008 we were assigned a liaison from Microsoft that had a much larger block of time to coordinate with us.  That changed everything between PASS and Microsoft.  Suddenly we were talking to product marketing, Microsoft PR, their event team, the Tech*Ed team, the education division, their user group team and their field sales team – locally and internationally.  We strengthened our relationship with CSS, SQLCAT and the engineering teams.  We had exposure at the executive level that we’d never had before.  And their level of participation at the Summit changed from under 100 people to 400-500 people.  I think those 400+ Microsoft employees have value at a conference on Microsoft SQL Server.  For the first time, Seattle had a real competitive advantage over other cities. I’m one that looked very hard at staying in Seattle for a long, long time.  I think those Microsoft engineers have value to our attendees.  I think the increased support that Microsoft can provide when we’re in Seattle has value to our attendees.  But that doesn’t tell the whole story.  There’s a significant (and vocal!) percentage of our membership that wants the Summit outside Seattle.  Post-2007 PASS doesn’t know what it’s like to have a Summit outside of Seattle.  I think until we have a Summit in another city we won’t really know the trade-offs. I think a model where we move every third or every other year is interesting.  But until we have another Summit outside Seattle and we can evaluate the logistics and how important it is to have depth and variety in our Microsoft participation we won’t really know. Another benefit that comes with a move is variety or diversity.  I learn more when I’m exposed to new things and new people.  I believe that moving the Summit will give a different set of people an opportunity to attend. Grant Fritchey writes “It seems that the board is leaning, extremely heavily, towards making it a permanent fixture in Seattle.”  I don’t believe that’s true.  I know there was discussion of that earlier but I don’t believe it’s true now. And that brings me to my question.  Do we announce the city now or do we wait until the 2012 Summit?  I’m happy to announce Seattle vs. not-Seattle as soon as we sign the contract.  But I’d like to leave the actual city announcement until the 2011 Summit.  I like the drama and mystery of it.  I also like that it doesn’t give you a reason to skip a Summit and wait for the next one if it’s closer or back in Seattle.  The other side of the coin is that your planning is easier if you know where it is.  What do you think?

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• How to Achieve Real-Time Data Protection and Availabilty....For Real

  - by JoeMeeks

  There is a class of business and mission critical applications where downtime or data loss have substantial negative impact on revenue, customer service, reputation, cost, etc. Because the Oracle Database is used extensively to provide reliable performance and availability for this class of application, it also provides an integrated set of capabilities for real-time data protection and availability. Active Data Guard, depicted in the figure below, is the cornerstone for accomplishing these objectives because it provides the absolute best real-time data protection and availability for the Oracle Database. This is a bold statement, but it is supported by the facts. It isn’t so much that alternative solutions are bad, it’s just that their architectures prevent them from achieving the same levels of data protection, availability, simplicity, and asset utilization provided by Active Data Guard. Let’s explore further. Backups are the most popular method used to protect data and are an essential best practice for every database. Not surprisingly, Oracle Recovery Manager (RMAN) is one of the most commonly used features of the Oracle Database. But comparing Active Data Guard to backups is like comparing apples to motorcycles. Active Data Guard uses a hot (open read-only), synchronized copy of the production database to provide real-time data protection and HA. In contrast, a restore from backup takes time and often has many moving parts - people, processes, software and systems – that can create a level of uncertainty during an outage that critical applications can’t afford. This is why backups play a secondary role for your most critical databases by complementing real-time solutions that can provide both data protection and availability. Before Data Guard, enterprises used storage remote-mirroring for real-time data protection and availability. Remote-mirroring is a sophisticated storage technology promoted as a generic infrastructure solution that makes a simple promise – whatever is written to a primary volume will also be written to the mirrored volume at a remote site. Keeping this promise is also what causes data loss and downtime when the data written to primary volumes is corrupt – the same corruption is faithfully mirrored to the remote volume making both copies unusable. This happens because remote-mirroring is a generic process. It has no  intrinsic knowledge of Oracle data structures to enable advanced protection, nor can it perform independent Oracle validation BEFORE changes are applied to the remote copy. There is also nothing to prevent human error (e.g. a storage admin accidentally deleting critical files) from also impacting the remote mirrored copy. Remote-mirroring tricks users by creating a false impression that there are two separate copies of the Oracle Database. In truth; while remote-mirroring maintains two copies of the data on different volumes, both are part of a single closely coupled system. Not only will remote-mirroring propagate corruptions and administrative errors, but the changes applied to the mirrored volume are a result of the same Oracle code path that applied the change to the source volume. There is no isolation, either from a storage mirroring perspective or from an Oracle software perspective.  Bottom line, storage remote-mirroring lacks both the smarts and isolation level necessary to provide true data protection. Active Data Guard offers much more than storage remote-mirroring when your objective is protecting your enterprise from downtime and data loss. Like remote-mirroring, an Active Data Guard replica is an exact block for block copy of the primary. Unlike remote-mirroring, an Active Data Guard replica is NOT a tightly coupled copy of the source volumes - it is a completely independent Oracle Database. Active Data Guard’s inherent knowledge of Oracle data block and redo structures enables a separate Oracle Database using a different Oracle code path than the primary to use the full complement of Oracle data validation methods before changes are applied to the synchronized copy. These include: physical check sum, logical intra-block checking, lost write validation, and automatic block repair. The figure below illustrates the stark difference between the knowledge that remote-mirroring can discern from an Oracle data block and what Active Data Guard can discern. An Active Data Guard standby also provides a range of additional services enabled by the fact that it is a running Oracle Database - not just a mirrored copy of data files. An Active Data Guard standby database can be open read-only while it is synchronizing with the primary. This enables read-only workloads to be offloaded from the primary system and run on the active standby - boosting performance by utilizing all assets. An Active Data Guard standby can also be used to implement many types of system and database maintenance in rolling fashion. Maintenance and upgrades are first implemented on the standby while production runs unaffected at the primary. After the primary and standby are synchronized and all changes have been validated, the production workload is quickly switched to the standby. The only downtime is the time required for user connections to transfer from one system to the next. These capabilities further expand the expectations of availability offered by a data protection solution beyond what is possible to do using storage remote-mirroring. So don’t be fooled by appearances.  Storage remote-mirroring and Active Data Guard replication may look similar on the surface - but the devil is in the details. Only Active Data Guard has the smarts, the isolation, and the simplicity, to provide the best data protection and availability for the Oracle Database. Stay tuned for future blog posts that dive into the many differences between storage remote-mirroring and Active Data Guard along the dimensions of data protection, data availability, cost, asset utilization and return on investment. For additional information on Active Data Guard, see: Active Data Guard Technical White Paper Active Data Guard vs Storage Remote-Mirroring Active Data Guard Home Page on the Oracle Technology Network

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• Organization &amp; Architecture UNISA Studies &ndash; Chap 5

  - by MarkPearl

  Learning Outcomes Describe the operation of a memory cell Explain the difference between DRAM and SRAM Discuss the different types of ROM Explain the concepts of a hard failure and a soft error respectively Describe SDRAM organization Semiconductor Main Memory The two traditional forms of RAM used in computers are DRAM and SRAM DRAM (Dynamic RAM) Divided into two technologies… Dynamic Static Dynamic RAM is made with cells that store data as charge on capacitors. The presence or absence of charge in a capacitor is interpreted as a binary 1 or 0. Because capacitors have natural tendency to discharge, dynamic RAM requires periodic charge refreshing to maintain data storage. The term dynamic refers to the tendency of the stored charge to leak away, even with power continuously applied. Although the DRAM cell is used to store a single bit (0 or 1), it is essentially an analogue device. The capacitor can store any charge value within a range, a threshold value determines whether the charge is interpreted as a 1 or 0. SRAM (Static RAM) SRAM is a digital device that uses the same logic elements used in the processor. In SRAM, binary values are stored using traditional flip flop logic configurations. SRAM will hold its data as along as power is supplied to it. Unlike DRAM, no refresh is required to retain data. SRAM vs. DRAM DRAM is simpler and smaller than SRAM. Thus it is more dense and less expensive than SRAM. The cost of the refreshing circuitry for DRAM needs to be considered, but if the machine requires a large amount of memory, DRAM turns out to be cheaper than SRAM. SRAMS are somewhat faster than DRAM, thus SRAM is generally used for cache memory and DRAM is used for main memory. Types of ROM Read Only Memory (ROM) contains a permanent pattern of data that cannot be changed. ROM is non volatile meaning no power source is required to maintain the bit values in memory. While it is possible to read a ROM, it is not possible to write new data into it. An important application of ROM is microprogramming, other applications include library subroutines for frequently wanted functions, System programs, Function tables. A ROM is created like any other integrated circuit chip, with the data actually wired into the chip as part of the fabrication process. To reduce costs of fabrication, we have PROMS. PROMS are… Written only once Non-volatile Written after fabrication Another variation of ROM is the read-mostly memory, which is useful for applications in which read operations are far more frequent than write operations, but for which non volatile storage is required. There are three common forms of read-mostly memory, namely… EPROM EEPROM Flash memory Error Correction Semiconductor memory is subject to errors, which can be classed into two categories… Hard failure – Permanent physical defect so that the memory cell or cells cannot reliably store data Soft failure – Random error that alters the contents of one or more memory cells without damaging the memory (common cause includes power supply issues, etc.) Most modern main memory systems include logic for both detecting and correcting errors. Error detection works as follows… When data is to be read into memory, a calculation is performed on the data to produce a code Both the code and the data are stored When the previously stored word is read out, the code is used to detect and possibly correct errors The error checking provides one of 3 possible results… No errors are detected – the fetched data bits are sent out An error is detected, and it is possible to correct the error. The data bits plus error correction bits are fed into a corrector, which produces a corrected set of bits to be sent out An error is detected, but it is not possible to correct it. This condition is reported Hamming Code See wiki for detailed explanation. We will probably need to know how to do a hemming code – refer to the textbook (pg. 188 – 189) Advanced DRAM organization One of the most critical system bottlenecks when using high-performance processors is the interface to main memory. This interface is the most important pathway in the entire computer system. The basic building block of main memory remains the DRAM chip. In recent years a number of enhancements to the basic DRAM architecture have been explored, and some of these are now on the market including… SDRAM (Synchronous DRAM) DDR-DRAM RDRAM SDRAM (Synchronous DRAM) SDRAM exchanges data with the processor synchronized to an external clock signal and running at the full speed of the processor/memory bus without imposing wait states. SDRAM employs a burst mode to eliminate the address setup time and row and column line precharge time after the first access In burst mode a series of data bits can be clocked out rapidly after the first bit has been accessed SDRAM has a multiple bank internal architecture that improves opportunities for on chip parallelism SDRAM performs best when it is transferring large blocks of data serially There is now an enhanced version of SDRAM known as double data rate SDRAM or DDR-SDRAM that overcomes the once-per-cycle limitation of SDRAM

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• Design Pattern for Complex Data Modeling

  - by Aaron Hayman

  I'm developing a program that has a SQL database as a backing store. As a very broad description, the program itself allows a user to generate records in any number of user-defined tables and make connections between them. As for specs: Any record generated must be able to be connected to any other record in any other user table (excluding itself...the record, not the table). These "connections" are directional, and the list of connections a record has is user ordered. Moreover, a record must "know" of connections made from it to others as well as connections made to it from others. The connections are kind of the point of this program, so there is a strong possibility that the number of connections made is very high, especially if the user is using the software as intended. A record's field can also include aggregate information from it's connections (like obtaining average, sum, etc) that must be updated on change from another record it's connected to. To conserve memory, only relevant information must be loaded at any one time (can't load the entire database in memory at load and go from there). I cannot assume the backing store is local. Right now it is, but eventually this program will include syncing to a remote db. Neither the user tables, connections or records are known at design time as they are user generated. I've spent a lot of time trying to figure out how to design the backing store and the object model to best fit these specs. In my first design attempt on this, I had one object managing all a table's records and connections. I attempted this first because it kept the memory footprint smaller (records and connections were simple dicts), but maintaining aggregate and link information between tables became....onerous (ie...a huge spaghettified mess). Tracing dependencies using this method almost became impossible. Instead, I've settled on a distributed graph model where each record and connection is 'aware' of what's around it by managing it own data and connections to other records. Doing this increases my memory footprint but also let me create a faulting system so connections/records aren't loaded into memory until they're needed. It's also much easier to code: trace dependencies, eliminate cycling recursive updates, etc. My biggest problem is storing/loading the connections. I'm not happy with any of my current solutions/ideas so I wanted to ask and see if anybody else has any ideas of how this should be structured. Connections are fairly simple. They contain: fromRecordID, fromTableID, fromRecordOrder, toRecordID, toTableID, toRecordOrder. Here's what I've come up with so far: Store all the connections in one big table. If I do this, either I load all connections at once (one big db call) or make a call every time a user table is loaded. The big issue here: the size of the connections table has the potential to be huge, and I'm afraid it would slow things down. Store in separate tables all the outgoing connections for each user table. This is probably the worst idea I've had. Now my connections are 'spread out' over multiple tables (one for each user table), which means I have to make a separate DB called to each table (or make a huge join) just to find all the incoming connections for a particular user table. I've avoided making "one big ass table", but I'm not sure the cost is worth it. Store in separate tables all outgoing AND incoming connections for each user table (using a flag to distinguish between incoming vs outgoing). This is the idea I'm leaning towards, but it will essentially double the total DB storage for all the connections (as each connection will be stored in two tables). It also means I have to make sure connection information is kept in sync in both places. This is obviously not ideal but it does mean that when I load a user table, I only need to load one 'connection' table and have all the information I need. This also presents a separate problem, that of connection object creation. Since each user table has a list of all connections, there are two opportunities for a connection object to be made. However, connections objects (designed to facilitate communication between records) should only be created once. This means I'll have to devise a common caching/factory object to make sure only one connection object is made per connection. Does anybody have any ideas of a better way to do this? Once I've committed to a particular design pattern I'm pretty much stuck with it, so I want to make sure I've come up with the best one possible.

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• Implications of Java 6 End of Public Updates for EBS Users

  - by Steven Chan (Oracle Development)

  The Support Roadmap for Oracle Java is published here: Oracle Java SE Support Roadmap The latest updates to that page (as of Sept. 19, 2012) state (emphasis added): Java SE 6 End of Public Updates Notice After February 2013, Oracle will no longer post updates of Java SE 6 to its public download sites. Existing Java SE 6 downloads already posted as of February 2013 will remain accessible in the Java Archive on Oracle Technology Network. Developers and end-users are encouraged to update to more recent Java SE versions that remain available for public download. For enterprise customers, who need continued access to critical bug fixes and security fixes as well as general maintenance for Java SE 6 or older versions, long term support is available through Oracle Java SE Support . What does this mean for Oracle E-Business Suite users? EBS users fall under the category of "enterprise users" above.  Java is an integral part of the Oracle E-Business Suite technology stack, so EBS users will continue to receive Java SE 6 updates after February 2013. In other words, nothing will change for EBS users after February 2013.  EBS users will continue to receive critical bug fixes and security fixes as well as general maintenance for Java SE 6. These Java SE 6 updates will be made available to EBS users for the Extended Support periods documented in the Oracle Lifetime Support policy document for Oracle Applications (PDF): EBS 11i Extended Support ends November 2013 EBS 12.0 Extended Support ends January 2015 EBS 12.1 Extended Support ends December 2018 Will EBS users be forced to upgrade to JRE 7 for Windows desktop clients? No. This upgrade will be highly recommended but currently remains optional. JRE 6 will be available to Windows users to run with EBS for the duration of your respective EBS Extended Support period.  Updates will be delivered via My Oracle Support, where you can continue to receive critical bug fixes and security fixes as well as general maintenance for JRE 6 desktop clients.  The certification of Oracle E-Business Suite with JRE 7 (for desktop clients accessing EBS Forms-based content) is in its final stages.  If you plan to upgrade your EBS desktop clients to JRE 7 when that certification is released, you can get a head-start on that today. Coexistence of JRE 6 and JRE 7 on Windows desktops The upgrade to JRE 7 will be highly recommended for EBS users, but some users may need to run both JRE 6 and 7 on their Windows desktops for reasons unrelated to the E-Business Suite. Most EBS configurations with IE and Firefox use non-static versioning by default. JRE 7 will be invoked instead of JRE 6 if both are installed on a Windows desktop. For more details, see "Appendix B: Static vs. Non-static Versioning and Set Up Options" in Notes 290801.1 and 393931.1. Applying Updates to JRE 6 and JRE 7 to Windows desktops Auto-update will keep JRE 7 up-to-date for Windows users with JRE 7 installed. Auto-update will only keep JRE 7 up-to-date for Windows users with both JRE 6 and 7 installed.  JRE 6 users are strongly encouraged to apply the latest Critical Patch Updates as soon as possible after each release. The Jave SE CPUs will be available via My Oracle Support.  EBS users can find more information about JRE 6 and 7 updates here: Information Center: Installation & Configuration for Oracle Java SE (Note 1412103.2) The dates for future Java SE CPUs can be found on the Critical Patch Updates, Security Alerts and Third Party Bulletin.  An RSS feed is available on that site for those who would like to be kept up-to-date. What will Mac users need? Oracle will provide updates to JRE 7 for Mac OS X users. EBS users running Macs will need to upgrade to JRE 7 to receive JRE updates. The certification of Oracle E-Business Suite with JRE 7 for Mac-based desktop clients accessing EBS Forms-based content is underway. Mac users waiting for that certification may find this article useful: How to Reenable Apple Java 6 Plug-in for Mac EBS Users Will EBS users be forced to upgrade to JDK 7 for EBS application tier servers? No. This upgrade will be highly recommended but will be optional for EBS application tier servers running on Windows, Linux, and Solaris.  You can choose to remain on JDK 6 for the duration of your respective EBS Extended Support period.  If you remain on JDK 6, you will continue to receive critical bug fixes and security fixes as well as general maintenance for JDK 6. The certification of Oracle E-Business Suite with JDK 7 for EBS application tier servers on Windows, Linux, and Solaris as well as other platforms such as IBM AIX and HP-UX is planned.  Customers running platforms other than Windows, Linux, and Solaris should refer to their Java vendors's sites for more information about their support policies. Related Articles Planning Bulletin for JRE 7: What EBS Customers Can Do Today EBS 11i and 12.1 Support Timeline Changes Frequently Asked Questions about Latest EBS Support Changes Critical Patch Updates During EBS 11i Exception to Sustaining Support Period

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• Drawing on a webpage – HTML5 - IE9

  - by nmarun

  So I upgraded to IE9 and continued exploring HTML5. Now there’s this ‘thing’ called Canvas in HTML5 with which you can do some cool stuff. Alright what IS this Canvas thing anyways? The Web Hypertext Application Technology Working Group says this: “The canvas element provides scripts with a resolution-dependent bitmap canvas, which can be used for rendering graphs, game graphics, or other visual images on the fly.” The Canvas element has two only attributes – width and height and when not specified they take up the default values of 300 and 150 respectively. Below is what my HTML file looks like: 1: <!DOCTYPE html> 2: <html lang="en-US"> 3: <head> 4: <script type="text/javascript" src="CustomScript.js"></script> 5: <script src="jquery-1.4.4.js" type="text/javascript"></script 6:  7: <title>Draw on a webpage</title> 8: </head> 9: <body> 10: <canvas id="canvas" width="500" height="500"></canvas> 11: <br /> 12: <input type="submit" id="submit" value="Clear" /> 13: <h4 id="currentPosition"> 14: 0, 0 15: </h4> 16: <div id="mousedownCoords"></div> 17: </body> 18: </html> In case you’re wondering, this is not a MVC or any kind of web application. This is plain ol’ HTML even though I’m writing all this in VS 2010. You see this is a very simple, ‘gimmicks-free’ html page. I have declared a Canvas element on line 10 and a button on line 11 to clear the drawing board. I’m using jQuery / JavaScript show the current position of the mouse on the screen. This will get updated in the ‘currentPosition’ <h4> tag and I’m using the ‘mousedownCoords’ to write all the places where the mouse was clicked. This is what my page renders as: The rectangle with a background is our canvas. The coloring is due to some javascript (which we’ll see in a moment). Now let’s get to our CustomScript.js file. 1: jQuery(document).ready(function () { 2: var isFirstClick = true; 3: var canvas = document.getElementById("canvas"); 4: // getContext: Returns an object that exposes an API for drawing on the canvas 5: var canvasContext = canvas.getContext("2d"); 6: fillBackground(); 7:  8: $("#submit").click(function () { 9: clearCanvas(); 10: fillBackground(); 11: }); 12:  13: $(document).mousemove(function (e) { 14: $('#currentPosition').html(e.pageX + ', ' + e.pageY); 15: }); 16: $(document).mouseup(function (e) { 17: // on the first click 18: // set the moveTo 19: if (isFirstClick == true) { 20: canvasContext.beginPath(); 21: canvasContext.moveTo(e.pageX - 7, e.pageY - 7); 22: isFirstClick = false; 23: } 24: else { 25: // on subsequent clicks, draw a line 26: canvasContext.lineTo(e.pageX - 7, e.pageY - 7); 27: canvasContext.stroke(); 28: } 29:  30: $('#mousedownCoords').text($('#mousedownCoords').text() + '(' + e.pageX + ',' + e.pageY + ')'); 31: }); 32:  33: function fillBackground() { 34: canvasContext.fillStyle = '#a1b1c3'; 35: canvasContext.fillRect(0, 0, 500, 500); 36: canvasContext.fill(); 37: } 38:  39: function clearCanvas() { 40: // wipe-out the canvas 41: canvas.width = canvas.width; 42: // set the isFirstClick to true 43: // so the next shape can begin 44: isFirstClick = true; 45: // clear the text 46: $('#mousedownCoords').text(''); 47: } 48: })   The script only looks long and complicated, but is not. I’ll go over the main steps. Get a ‘hold’ of your canvas object and retrieve the ‘2d’ context out of it. On mousemove event, write the current x and y coordinates to the ‘currentPosition’ element. On mouseup event, check if this is the first time the user has clicked on the canvas. The coloring of the canvas is done in the fillBackground() function. We first need to start a new path. This is done by calling the beginPath() function on our context. The moveTo() function sets the starting point of our path. The lineTo() function sets the end point of the line to be drawn. The stroke() function is the one that actually draws the line on our canvas. So if you want to play with the demo, here’s how you do it. First click on the canvas (nothing visible happens on the canvas). The second click draws a line from the first click to the current coordinates and so on and so forth. Click on the ‘Clear’ button, to reset the canvas and to give your creativity a clean slate. Here’s a sample output: Happy drawing! Verdict: HTML5 and IE9 – I think we’re on to something big and great here!

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• Configuring Application/User Settings in WPF the easy way.

  - by mbcrump

  In this tutorial, we are going to configure the application/user settings in a WPF application the easy way. Most example that I’ve seen on the net involve the ConfigurationManager class and involve creating your own XML file from scratch. I am going to show you a easier way to do it. (in my humble opinion) First, the definitions: User Setting – is designed to be something specific to the user. For example, one user may have a requirement to see certain stocks, news articles or local weather. This can be set at run-time. Application Setting – is designed to store information such as a database connection string. These settings are read-only at run-time. 1) Lets create a new WPF Project and play with a few settings. Once you are inside VS, then paste the following code snippet inside the <Grid> tags. <Grid> <TextBox Height="23" HorizontalAlignment="Left" Margin="12,11,0,0" Name="textBox1" VerticalAlignment="Top" Width="285" Grid.ColumnSpan="2" /> <Button Content="Set Title" Name="button2" Click="button2_Click" Margin="108,40,96,114" /> <TextBlock Height="23" Name="textBlock1" Text="TextBlock" VerticalAlignment="Bottom" Width="377" /> </Grid> Basically, its just a Textbox, Button and TextBlock. The main Window should look like the following:   2) Now we are going to setup our Configuration Settings. Look in the Solution Explorer and double click on the Settings.settings file. Make sure that your settings file looks just like mine included below:   What just happened was the designer created an XML file and created the Settings.Designer.cs file which looks like this: //------------------------------------------------------------------------------ // <auto-generated> // This code was generated by a tool. // Runtime Version:4.0.30319.1 // // Changes to this file may cause incorrect behavior and will be lost if // the code is regenerated. // </auto-generated> //------------------------------------------------------------------------------ namespace WPFExam.Properties { [global::System.Runtime.CompilerServices.CompilerGeneratedAttribute()] [global::System.CodeDom.Compiler.GeneratedCodeAttribute("Microsoft.VisualStudio.Editors.SettingsDesigner.SettingsSingleFileGenerator", "10.0.0.0")] internal sealed partial class Settings : global::System.Configuration.ApplicationSettingsBase { private static Settings defaultInstance = ((Settings)(global::System.Configuration.ApplicationSettingsBase.Synchronized(new Settings()))); public static Settings Default { get { return defaultInstance; } } [global::System.Configuration.UserScopedSettingAttribute()] [global::System.Diagnostics.DebuggerNonUserCodeAttribute()] [global::System.Configuration.DefaultSettingValueAttribute("ApplicationName")] public string ApplicationName { get { return ((string)(this["ApplicationName"])); } set { this["ApplicationName"] = value; } } [global::System.Configuration.ApplicationScopedSettingAttribute()] [global::System.Diagnostics.DebuggerNonUserCodeAttribute()] [global::System.Configuration.DefaultSettingValueAttribute("SQL_SRV342")] public string DatabaseServerName { get { return ((string)(this["DatabaseServerName"])); } } } } The XML File is named app.config and looks like this: <?xml version="1.0" encoding="utf-8" ?> <configuration> <configSections> <sectionGroup name="userSettings" type="System.Configuration.UserSettingsGroup, System, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" > <section name="WPFExam.Properties.Settings" type="System.Configuration.ClientSettingsSection, System, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" allowExeDefinition="MachineToLocalUser" requirePermission="false" /> </sectionGroup> <sectionGroup name="applicationSettings" type="System.Configuration.ApplicationSettingsGroup, System, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" > <section name="WPFExam.Properties.Settings" type="System.Configuration.ClientSettingsSection, System, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" requirePermission="false" /> </sectionGroup> </configSections> <userSettings> <WPFExam.Properties.Settings> <setting name="ApplicationName" serializeAs="String"> <value>ApplicationName</value> </setting> </WPFExam.Properties.Settings> </userSettings> <applicationSettings> <WPFExam.Properties.Settings> <setting name="DatabaseServerName" serializeAs="String"> <value>SQL_SRV342</value> </setting> </WPFExam.Properties.Settings> </applicationSettings> </configuration> 3) The only left now is the code behind the button. Double click the button and replace the MainWindow() method with the following code snippet. public MainWindow() { InitializeComponent(); this.Title = Properties.Settings.Default.ApplicationName; textBox1.Text = Properties.Settings.Default.ApplicationName; textBlock1.Text = Properties.Settings.Default.DatabaseServerName; } private void button2_Click(object sender, RoutedEventArgs e) { Properties.Settings.Default.ApplicationName = textBox1.Text.ToString(); Properties.Settings.Default.Save(); } Run the application and type something in the textbox and hit the Set Title button. Now, restart the application and you should see the text that you entered earlier.   If you look at the button2 click event, you will see that it was actually 2 lines of codes to save to the configuration file. I hope this helps, for more information consult MSDN.

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• Extending Blend for Visual Studio 2013

  - by Chris Skardon

  Originally posted on: http://geekswithblogs.net/cskardon/archive/2013/11/01/extending-blend-for-visual-studio-2013.aspxSo, I got a comment yesterday on my post about Extending Blend 4 and Blend for Visual Studio 2012 asking if I knew how to get it working for Blend for Visual Studio 2013.. My initial thoughts were, just change the location to get the blend dlls from Visual Studio 11.0 to 12.0 and you’re all set, so I went to do that, only to discover that the dlls I normally reference, well – they don’t exist. So… I’ve made a presumption that the actual process of using MEF etc is still the same. I was wrong. So, the route to discovery – required DotPeek and opening a few of blends dlls.. Browsing through the Blend install directory (./Microsoft Visual Studio 12.0/Blend/) I notice the .addin files: So I decide to peek into the SketchFlow dll, then promptly remember SketchFlow is quite a big thing, and hunting through there is not ideal, luckily there is another dll using an .addin file, ‘Microsoft.Expression.Importers.Host’, so we’ll go for that instead. We can see it’s still using the ‘IPackage’ formula, but where is that sucker? Well, we just press F12 on the ‘IPackage’ bit and DotPeek takes us there, with a very handy comment at the top: // Type: Microsoft.Expression.Framework.IPackage // Assembly: Microsoft.Expression.Framework, Version=12.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a // MVID: E092EA54-4941-463C-BD74-283FD36478E2 // Assembly location: C:\Program Files (x86)\Microsoft Visual Studio 12.0\Blend\Microsoft.Expression.Framework.dll Now we know where the IPackage interface is defined, so let’s just try writing a control. Last time I did a separate dll for the control, this time I’m not, but it still works if you want to do it that way. Let’s build a control! STEP 1 Create a new WPF application Naming doesn’t matter any more! I have gone with ‘Hello2013’ (see what I did there?) STEP 2 Delete: App.Config App.xaml MainWindow.xaml We won’t be needing them STEP 3 Change your application to be a Class Library instead. (You might also want to delete the ‘vshost’ stuff in your output directory now, as they only exist for hosting the WPF app, and just cause clutter) STEP 4 Add a reference to the ‘Microsoft.Expression.Framework.dll’ (which you can find in ‘C:\Program Files\Microsoft Visual Studio 12.0\Blend’ – that’s Program Files (x86) if you’re on an x64 machine!). STEP 5 Add a User Control, I’m going with ‘Hello2013Control’, and following from last time, it’s just a TextBlock in a Grid: <UserControl x:Class="Hello2013.Hello2013Control" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" xmlns:d="http://schemas.microsoft.com/expression/blend/2008" mc:Ignorable="d" d:DesignHeight="300" d:DesignWidth="300"> <Grid> <TextBlock>Hello Blend for VS 2013</TextBlock> </Grid> </UserControl> STEP 6 Add a class to load the package – I’ve called it – yes you guessed – Hello2013Package, which will look like this: namespace Hello2013 { using Microsoft.Expression.Framework; using Microsoft.Expression.Framework.UserInterface; public class Hello2013Package : IPackage { private Hello2013Control _hello2013Control; private IWindowService _windowService; public void Load(IServices services) { _windowService = services.GetService<IWindowService>(); Initialize(); } private void Initialize() { _hello2013Control = new Hello2013Control(); if (_windowService.PaletteRegistry["HelloPanel"] == null) _windowService.RegisterPalette("HelloPanel", _hello2013Control, "Hello Window"); } public void Unload(){} } } You might note that compared to the 2012 version we’re no longer [Exporting(typeof(IPackage))]. The file you create in STEP 7 covers this for us. STEP 7 Add a new file called: ‘<PROJECT_OUTPUT_NAME>.addin’ – in reality you can call it anything and it’ll still read it in just fine, it’s just nicer if it all matches up, so I have ‘Hello2013.addin’. Content wise, we need to have: <?xml version="1.0" encoding="utf-8"?> <AddIn AssemblyFile="Hello2013.dll" /> obviously, replacing ‘Hello2013.dll’ with whatever your dll is called. STEP 8 We set the ‘addin’ file to be copied to the output directory: STEP 9 Build! STEP 10 Go to your output directory (./bin/debug) and copy the 3 files (Hello2013.dll, Hello2013.pdb, Hello2013.addin) and then paste into the ‘Addins’ folder in your Blend directory (C:\Program Files\Microsoft Visual Studio 12.0\Blend\Addins) STEP 11 Start Blend for Visual Studio 2013 STEP 12 Go to the ‘Window’ menu and select ‘Hello Window’ STEP 13 Marvel at your new control! Feel free to email me / comment with any problems!

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• The Joy Of Hex

  - by Jim Giercyk

  While working on a mainframe integration project, it occurred to me that some basic computer concepts are slipping into obscurity. For example, just about anyone can tell you that a 64-bit processor is faster than a 32-bit processer. A grade school child could tell you that a computer “speaks” in ‘1’s and ‘0’s. Some people can even tell you that there are 8 bits in a byte. However, I have found that even the most seasoned developers often can’t explain the theory behind those statements. That is not a knock on programmers; in the age of IntelliSense, what reason do we have to work with data at the bit level? Many computer theory classes treat bit-level programming as a thing of the past, no longer necessary now that storage space is plentiful. The trouble with that mindset is that the world is full of legacy systems that run programs written in the 1970’s.  Today our jobs require us to extract data from those systems, regardless of the format, and that often involves low-level programming. Because it seems knowledge of the low-level concepts is waning in recent times, I thought a review would be in order.       CHARACTER: See Spot Run HEX: 53 65 65 20 53 70 6F 74 20 52 75 6E DECIMAL: 83 101 101 32 83 112 111 116 32 82 117 110 BINARY: 01010011 01100101 01100101 00100000 01010011 01110000 01101111 01110100 00100000 01010010 01110101 01101110 In this example, I have broken down the words “See Spot Run” to a level computers can understand – machine language.     CHARACTER:  The character level is what is rendered by the computer.  A “Character Set” or “Code Page” contains 256 characters, both printable and unprintable.  Each character represents 1 BYTE of data.  For example, the character string “See Spot Run” is 12 Bytes long, exclusive of the quotation marks.  Remember, a SPACE is an unprintable character, but it still requires a byte.  In the example I have used the default Windows character set, ASCII, which you can see here:  http://www.asciitable.com/ HEX:  Hex is short for hexadecimal, or Base 16.  Humans are comfortable thinking in base ten, perhaps because they have 10 fingers and 10 toes; fingers and toes are called digits, so it’s not much of a stretch.  Computers think in Base 16, with numeric values ranging from zero to fifteen, or 0 – F.  Each decimal place has a possible 16 values as opposed to a possible 10 values in base 10.  Therefore, the number 10 in Hex is equal to the number 16 in Decimal.  DECIMAL:  The Decimal conversion is strictly for us humans to use for calculations and conversions.  It is much easier for us humans to calculate that [30 – 10 = 20] in decimal than it is for us to calculate [1E – A = 14] in Hex.  In the old days, an error in a program could be found by determining the displacement from the entry point of a module.  Since those values were dumped from the computers head, they were in hex. A programmer needed to convert them to decimal, do the equation and convert back to hex.  This gets into relative and absolute addressing, a topic for another day.  BINARY:  Binary, or machine code, is where any value can be expressed in 1s and 0s.  It is really Base 2, because each decimal place can have a possibility of only 2 characters, a 1 or a 0.  In Binary, the number 10 is equal to the number 2 in decimal. Why only 1s and 0s?  Very simply, computers are made up of lots and lots of transistors which at any given moment can be ON ( 1 ) or OFF ( 0 ).  Each transistor is a bit, and the order that the transistors fire (or not fire) is what distinguishes one value from  another in the computers head (or CPU).  Consider 32 bit vs 64 bit processing…..a 64 bit processor has the capability to read 64 transistors at a time.  A 32 bit processor can only read half as many at a time, so in theory the 64 bit processor should be much faster.  There are many more factors involved in CPU performance, but that is the fundamental difference.    DECIMAL HEX BINARY 0 0 0000 1 1 0001 2 2 0010 3 3 0011 4 4 0100 5 5 0101 6 6 0110 7 7 0111 8 8 1000 9 9 1001 10 A 1010 11 B 1011 12 C 1100 13 D 1101 14 E 1110 15 F 1111   Remember that each character is a BYTE, there are 2 HEX characters in a byte (called nibbles) and 8 BITS in a byte.  I hope you enjoyed reading about the theory of data processing.  This is just a high-level explanation, and there is much more to be learned.  It is safe to say that, no matter how advanced our programming languages and visual studios become, they are nothing more than a way to interpret bits and bytes.  There is nothing like the joy of hex to get the mind racing.

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• Some New .NET Downloads and Resources

  - by Kevin Grossnicklaus

  Last week I was fortunate enough to spend time in Redmond on Microsoft’s campus for the 2011 Microsoft MVP Summit.  It was great to hang out with a number of old friends and get the opportunity to talk tech with the various product teams up at Microsoft.  The weather wasn’t exactly sunny but Microsoft always does a great job with the Summit and everyone had a blast (heck, I even got to run the bases at SafeCo field) While much of what we saw is covered under NDA, there a ton of great things in the pipeline from Microsoft and many things that are already available (or just became so) that I wasn’t necessarily aware of.  The purpose of this post is to share some of the info I learned on resources and tools available to .NET developers today.  Please let me know if you have any questions (or if you know of something else cool which might benefit others). Enjoy! Visual Studio 2010 SP1 Microsoft has issued the RTM release of Visual Studio 2010 SP1.  You can download the full SP1 on MSDN as of today (March 10th to the general public) and take advantage of such things as: Silverlight 4 is included in the box (as opposed to a separate install) Silverlight 4 Profiling WCF RIA Services SP1 Intellitrace for 64-bit and SharePoint ASP.NET now easily supports IIS Express and SQL CE Want a description of all that’s new beyond the above biased list (which arguably only contains items I think are important)?  Check out this KB article. Portable Library Tools CTP Without much fanfare Microsoft has released a CTP of a new add-in to Visual Studio 2010 which simplifies code sharing between projects targeting different runtimes (i.e. Silverlight, WPF, Win7 Phone, XBox).   With this Add-In installed you can add a new project of type “Portable Library” and specify which platforms you wish to target.  Once that is done, any code added to this library will be limited to use only features which are common to all selected frameworks.  Other projects can now reference this portable library and be provided assemblies custom built to their environment.  This greatly simplifies the current process of sharing linked files between platforms like WPF and Silverlight.  You can find out more about this CTP and how it works on this great blog post. Visual Studio Async CTP Microsoft has also released a CTP of a set of language and framework enhancements to provide a much more powerful asynchronous programming model.   Due to the focus on async programming in all types of platforms (and it being the ONLY option in Silverlight and Win7 phone) a move towards a simpler and more understandable model is always a good thing. This CTP (called Visual Studio Async CTP) can be downloaded here.  You can read more about this CTP on this blog post. MSDN Code Samples Gallery Microsoft has also launched new code samples gallery on their MSDN site: http://code.msdn.microsoft.com/.   This site allows you to easily search for small samples of code related to a particular technology or platform.  If a sample of code you are looking for is not found, you can request one via the site and other developers can see your request and provide a sample to the site to suit your needs.  You can also peruse requested samples and, if you find a scenario where you can provide value, upload your own sample for the benefit of others.  Samples are packaged into the VS .vsix format and include any necessary references/dependencies.  By using .vsix as the deployment mechanism, as samples are installed from the site they are kept in your Visual Studio 2010 Samples Gallery and kept for your future reference. If you get a chance, check out the site and see how it is done.  Although a somewhat simple concept, I was very impressed with their implementation and the way they went about trying to suit a need.  I’ll definitely be looking there in the future as need something or want to share something. MSDN Search Capabilities Another item I learned recently and was not aware of (that might seem trivial to some) is the power of the MSDN site’s search capabilities.  Between the Code Samples Gallery described above and the search enhancements on MSDN, Microsoft is definitely investing in their platform to help provide developers of all skill levels the tools and resources they need to be successful. What do I mean by the MSDN search capability and why should you care? If you go to the MSDN home page (http://msdn.microsoft.com) and use the “Search MSDN with Big” box at the very top of the page you will see some very interesting results.  First, the search actually doesn’t just search the MSDN library it searches: MSDN Library All Microsoft Blogs CodePlex StackOverflow Downloads MSDN Magazine Support Knowledgebase (I’m not sure it even ends there but the above are all I know of) Beyond just searching all the above locations, the results are formatted very nicely to give some contextual information based on where the result came from.  For example, if a keyword search returned results from CodePlex, each row in the search results screen would include a large amount of information specific to CodePlex such as: Looking at the above results immediately tells you everything from the page views to the CodePlex ratings.  All in all, knowing that this much information is indexed and available from a single search location will lead me to utilize this as one of my initial searches for development information.

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• Application Development: Python or Java (or PHP)

  - by luckysmack

  I'm looking to get into application development, such as Facebook or Android apps and games. I am doing this for fun and to learn. Once my skills are to par I would like to have some side income from the apps, but I'm not banking on living off that (just so you know where I'm coming from and know what my end goals are). Currently I know and am familiar with PHP and frameworks such as cakephp and yii. However, I have been wanting to learn another language to broaden my horizons and to become a better developer. So I have narrowed it down to 2 languages. Python, and Java (I can already hear people cringing at the difference in the languages I have chosen, but I have some reasons). Python: closer to PHP that Java. Cross platformability. Also great as a general scripting language and has many file system level benefits that PHP does not. Cleaner syntax, readability, blah blah and the list goed on. Python will work great for cross platform apps and can be run on many OS's and is supported by Facebook for app development. But there is no support on Android (for full fledged apps). Java: a much stronger typed language, very robust community and corporate backing. Knowing Java is also good for personal marketability for enterprises, if you're into that. The main benefit here is that Java can write apps natively for Android and the apps can be ported for web versions to play on Facebook. So while I have seen many developers prefer Java over the two, Java has this significant advantage, where I can market my apps in both markets and in the future build more potential income. But like I said it is for fun. While money isn't the goal, it would still be nice. PHP: I'm putting this here because I know it already, and I'm sure a case could be made for it. It obviously works great for Facebook but like Python does not do so well on android. While it's mostly the realm of 'application development' that appeals to me, I do find Android apps fairly interesting and something that has a ton of potential to. But then again Facebook has a ton more users and the apps can also potentially be more immersive (desktop vs. mobile). So this is why I'm kinda stuck on what route to choose. Python for Facebook and web apps, with likely faster development to production times, or Java which can be developed for any of the platforms to make apps. Side note: I'm not really trying to get into 3D development, mostly 2D. And I also want to make an app with real-time play (websockets, etc). Someone mentioned node, js to me for that but Python seems to be more globally versatile for my goals. So, to anyone that does Facebook or Android development in either language: what do you suggest? Any input is valuable and I do appreciate it. And sorry for being long winded. EDIT: as mentioned in one of the answers, my primary goal is gaming. Although I do have some plans for non gaming apps such as general web based and desktop based ones. But gaming is my main goal with the possibility of income. EDIT: Another consideration could be Jython. Writing Python code which is converted into Java bytecode. This would allow the ability to do Android apps using Python. I could be wrong though, I'm still looking into it. Update 1-26-11: I recently acquired a new job which required I learn .NET using C#. Im sure some of you are cringing already but I really like the whole system and how it all works together between desktop and web development. But, as I am still interested in Python very much, and after some research I have decided I will learn Python as well as the IronPython implementation for .NET. But (again: I know...) since .NET is mostly a Windows thing and not as cross-compatible as I like, I will be learning Mono which is a cross platform implementation of .NET where I can use what I learn at work using C# and what I want to learn, Python/IronPython. So while learning and writing C#/.NET @ work I will be learning Python - Mono - Iron Python for what I want to do personally. And the benefit of them all being very closely related will help me out a lot, I think. What do you guys think? I almost feel like that should be another question, but there's not much of a question. Either way, you guys gave very helpful input.

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• Building a plug-in for Windows Live Writer

  - by mbcrump

  This tutorial will show you how to build a plug-in for Windows Live Writer. Windows Live Writer is a blogging tool that Microsoft provides for free. It includes an open API for .NET developers to create custom plug-ins. In this tutorial, I will show you how easy it is to build one. Open VS2008 or VS2010 and create a new project. Set the target framework to 2.0, Application Type to Class Library and give it a name. In this tutorial, we are going to create a plug-in that generates a twitter message with your blog post name and a TinyUrl link to the blog post.  It will do all of this automatically after you publish your post. Once, we have a new projected created. We need to setup the references. Add a reference to the WindowsLive.Writer.Api.dll located in the C:\Program Files (x86)\Windows Live\Writer\ folder, if you are using X64 version of Windows. You will also need to add a reference to System.Windows.Forms System.Web from the .NET tab as well. Once that is complete, add your “using” statements so that it looks like whats shown below: Live Writer Plug-In "Using" using System; using System.Collections.Generic; using System.Text; using WindowsLive.Writer.Api; using System.Web; Now, we are going to setup some build events to make it easier to test our custom class. Go into the Properties of your project and select Build Events, click edit the Post-build and copy/paste the following line: XCOPY /D /Y /R "$(TargetPath)" "C:\Program Files (x86)\Windows Live\Writer\Plugins\" Your screen should look like the one pictured below: Next, we are going to launch an external program on debug. Click the debug tab and enter C:\Program Files (x86)\Windows Live\Writer\WindowsLiveWriter.exe Your screen should look like the one pictured below:   Now we have a blank project and we need to add some code. We start with adding the attributes for the Live Writer Plugin. Before we get started creating the Attributes, we need to create a GUID. This GUID will uniquely identity our plug-in. So, to create a GUID follow the steps in VS2008/2010. Click Tools from the VS Menu ->Create GUID It will generate a GUID like the one listed below: GUID <Guid("56ED8A2C-F216-420D-91A1-F7541495DBDA")> We only want what’s inside the quotes, so your final product should be: "56ED8A2C-F216-420D-91A1-F7541495DBDA". Go ahead and paste this snipped into your class just above the public class. Live Writer Plug-In Attributes [WriterPlugin("56ED8A2C-F216-420D-91A1-F7541495DBDA",    "Generate Twitter Message",    Description = "After your new post has been published, this plug-in will attempt to generate a Twitter status messsage with the Title and TinyUrl link.",    HasEditableOptions = false,    Name = "Generate Twitter Message",    PublisherUrl = "http://michaelcrump.net")] [InsertableContentSource("Generate Twitter Message")] So far, it should look like the following: Next, we need to implement the PublishNotifcationHook class and override the OnPostPublish. I’m not going to dive into what the code is doing as you should be able to follow pretty easily. The code below is the entire code used in the project. PublishNotificationHook public class Class1 :  PublishNotificationHook  {      public override void OnPostPublish(System.Windows.Forms.IWin32Window dialogOwner, IProperties properties, IPublishingContext publishingContext, bool publish)      {          if (!publish) return;          if (string.IsNullOrEmpty(publishingContext.PostInfo.Permalink))          {              PluginDiagnostics.LogError("Live Tweet didn't execute, due to blank permalink");          }          else          {                var strBlogName = HttpUtility.UrlEncode("#blogged : " + publishingContext.PostInfo.Title);  //Blog Post Title              var strUrlFinal = getTinyUrl(publishingContext.PostInfo.Permalink); //Blog Permalink URL Converted to TinyURL              System.Diagnostics.Process.Start("http://twitter.com/home?status=" + strBlogName + strUrlFinal);            }      } We are going to go ahead and create a method to create the short url (tinyurl). TinyURL Helper Method private static string getTinyUrl(string url) {     var cmpUrl = System.Globalization.CultureInfo.InvariantCulture.CompareInfo;     if (!cmpUrl.IsPrefix(url, "http://tinyurl.com"))     {         var address = "http://tinyurl.com/api-create.php?url=" + url;         var client = new System.Net.WebClient();         return (client.DownloadString(address));     }     return (url); } Go ahead and build your project, it should have copied the .DLL into the Windows Live Writer Plugin Directory. If it did not, then you will want to check your configuration. Once that is complete, open Windows Live Writer and select Tools-> Options-> Plug-ins and enable your plug-in that you just created. Your screen should look like the one pictured below: Go ahead and click OK and publish your blog post. You should get a pop-up with the following: Hit OK and It should open a Twitter and either ask for a login or fill in your status as shown below:   That should do it, you can do so many other things with the API. I suggest that if you want to build something really useful consult the MSDN pages. This plug-in that I created was perfect for what I needed and I hope someone finds it useful.

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• How to draw textures on a model

  - by marc wellman

  The following code is a complete XNA 3.1 program almost unaltered to that code skeleton Visual Studio is creating when creating a new project. The only things I have changed are imported a .x model to the content folder of the VS solution. (the model is a simple square with a texture spanning over it - made in Google Sketchup and exported with several .x exporters) in the Load() method I am loading the .x model into the game. The Draw() method uses a BasicEffect to render the model. Except these three things I haven't added any code. Why does the model does not show the texture ? What can I do to make the texture visible ? This is the texture file (a standard SketchUp texture from the palette): And this is what my program looks like - as you can see: No texture! Find below the complete source code of the program AND the complete .x file: namespace WindowsGame1 { /// <summary> /// This is the main type for your game /// </summary> public class Game1 : Microsoft.Xna.Framework.Game { GraphicsDeviceManager graphics; SpriteBatch spriteBatch; public Game1() { graphics = new GraphicsDeviceManager(this); Content.RootDirectory = "Content"; } /// <summary> /// Allows the game to perform any initialization it needs to before starting to run. /// This is where it can query for any required services and load any non-graphic /// related content. Calling base.Initialize will enumerate through any components /// and initialize them as well. /// </summary> protected override void Initialize() { // TODO: Add your initialization logic here base.Initialize(); } Model newModel; /// <summary> /// LoadContent will be called once per game and is the place to load /// all of your content. /// </summary> protected override void LoadContent() { // Create a new SpriteBatch, which can be used to draw textures. spriteBatch = new SpriteBatch(GraphicsDevice); // TODO: usse this.Content to load your game content here newModel = Content.Load<Model>(@"aau3d"); foreach (ModelMesh mesh in newModel.Meshes) { foreach (ModelMeshPart meshPart in mesh.MeshParts) { meshPart.Effect = new BasicEffect(this.GraphicsDevice, null); } } } /// <summary> /// UnloadContent will be called once per game and is the place to unload /// all content. /// </summary> protected override void UnloadContent() { // TODO: Unload any non ContentManager content here } /// <summary> /// Allows the game to run logic such as updating the world, /// checking for collisions, gathering input, and playing audio. /// </summary> /// <param name="gameTime">Provides a snapshot of timing values.</param> protected override void Update(GameTime gameTime) { // Allows the game to exit if (GamePad.GetState(PlayerIndex.One).Buttons.Back == ButtonState.Pressed) this.Exit(); // TODO: Add your update logic here base.Update(gameTime); } /// <summary> /// This is called when the game should draw itself. /// </summary> /// <param name="gameTime">Provides a snapshot of timing values.</param> protected override void Draw(GameTime gameTime) { if (newModel != null) { GraphicsDevice.Clear(Color.CornflowerBlue); Matrix[] transforms = new Matrix[newModel.Bones.Count]; newModel.CopyAbsoluteBoneTransformsTo(transforms); foreach (ModelMesh mesh in newModel.Meshes) { foreach (BasicEffect effect in mesh.Effects) { effect.EnableDefaultLighting(); effect.TextureEnabled = true; effect.World = transforms[mesh.ParentBone.Index] * Matrix.CreateRotationY(0) * Matrix.CreateTranslation(new Vector3(0, 0, 0)); effect.View = Matrix.CreateLookAt(new Vector3(200, 1000, 200), Vector3.Zero, Vector3.Up); effect.Projection = Matrix.CreatePerspectiveFieldOfView(MathHelper.ToRadians(45.0f), 0.75f, 1.0f, 10000.0f); } mesh.Draw(); } } base.Draw(gameTime); } } } This is the model I am using (.x): xof 0303txt 0032 // SketchUp 6 -> DirectX (c)2008 edecadoudal, supports: faces, normals and textures Material Default_Material{ 1.0;1.0;1.0;1.0;; 3.2; 0.000000;0.000000;0.000000;; 0.000000;0.000000;0.000000;; } Material _Groundcover_RiverRock_4inch_{ 0.568627450980392;0.494117647058824;0.427450980392157;1.0;; 3.2; 0.000000;0.000000;0.000000;; 0.000000;0.000000;0.000000;; TextureFilename { "aau3d.xGroundcover_RiverRock_4inch.jpg"; } } Mesh mesh_0{ 4; -81.6535;0.0000;74.8031;, -0.0000;0.0000;0.0000;, -81.6535;0.0000;0.0000;, -0.0000;0.0000;74.8031;; 2; 3;0,1,2, 3;1,0,3;; MeshMaterialList { 2; 2; 1, 1; { Default_Material } { _Groundcover_RiverRock_4inch_ } } MeshTextureCoords { 4; -2.1168,-3.4022; 1.0000,-0.0000; 1.0000,-3.4022; -2.1168,-0.0000;; } MeshNormals { 4; 0.0000;1.0000;-0.0000; 0.0000;1.0000;-0.0000; 0.0000;1.0000;-0.0000; 0.0000;1.0000;-0.0000;; 2; 3;0,1,2; 3;1,0,3;; } }

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• Changing the Game: Why Oracle is in the IT Operations Management Business

  - by DanKoloski

  v\:* {behavior:url(#default#VML);} o\:* {behavior:url(#default#VML);} w\:* {behavior:url(#default#VML);} .shape {behavior:url(#default#VML);} Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Calibri","sans-serif"; mso-bidi-font-family:"Times New Roman";} Next week, in Orlando, is the annual Gartner IT Operations Management Summit. Oracle is a premier sponsor of this annual event, which brings together IT executives for several days of high level talks about the state of operational management of enterprise IT. This year, Sushil Kumar, VP Product Strategy and Business Development for Oracle’s Systems & Applications Management, will be presenting on the transformation in IT Operations required to support enterprise cloud computing. IT Operations transformation is an important subject, because year after year, we hear essentially the same refrain – large enterprises spend an average of two-thirds (67%!) of their IT resources (budget, energy, time, people, etc.) on running the business, with far too little left over to spend on growing and transforming the business (which is what the business actually needs and wants). In the thirtieth year of the distributed computing revolution (give or take, depending on how you count it), it’s amazing that we have still not moved the needle on the single biggest component of enterprise IT resource utilization. Oracle is in the IT Operations Management business because when management is engineered together with the technology under management, the resulting efficiency gains can be truly staggering. To put it simply – what if you could turn that 67% of IT resources spent on running the business into 50%? Or 40%? Imagine what you could do with those resources. It’s now not just possible, but happening. This seems like a simple idea, but it is a radical change from “business as usual” in enterprise IT Operations. For the last thirty years, management has been a bolted-on afterthought – we pick and deploy our technology, then figure out how to manage it. This pervasive dysfunction is a broken cycle that guarantees high ongoing operating costs and low agility. If we want to break the cycle, we need to take a more tightly-coupled approach. As a complete applications-to-disk platform provider, Oracle is engineering management together with technology across our stack and hooking that on-premise management up live to My Oracle Support. Let’s examine the results with just one piece of the Oracle stack – the Oracle Database. Oracle began this journey with the Oracle Database 9i many years ago with the introduction of low-impact instrumentation in the database kernel (“tell me what’s wrong”) and through Database 10g, 11g and 11gR2 has successively added integrated advisory (“tell me how to fix what’s wrong”) and lifecycle management and automated self-tuning (“fix it for me, and do it on an ongoing basis for all my assets”). When enterprises take advantage of this tight-coupling, the results are game-changing. Consider the following (for a full list of public references, visit this link): British Telecom improved database provisioning time 1000% (from weeks to minutes) which allows them to provide a new DBaaS service to their internal customers with no additional resources Cerner Corporation Saved $9.5 million in CapEx and OpEx AND launched a brand-new cloud business at the same time Vodafone Group plc improved response times 50% and reduced maintenance planning times 50-60% while serving 391 million registered mobile customers Or the recent Database Manageability and Productivity Cost Comparisons: Oracle Database 11g Release 2 vs. SAP Sybase ASE 15.7, Microsoft SQL Server 2008 R2 and IBM DB2 9.7 as conducted by independent analyst firm ORC. In later entries, we’ll discuss similar results across other portions of the Oracle stack and how these efficiency gains are required to achieve the agility benefits of Enterprise Cloud. Stay Connected: Twitter |  Face book |  You Tube |  Linked in |  Newsletter

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• Specs, Form and Function – What am I Missing?

  - by Barry Shulam

  0 0 1 628 3586 08041 29 8 4206 14.0 Normal 0 false false false EN-US JA X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:Cambria; mso-ascii-font-family:Cambria; mso-ascii-theme-font:minor-latin; mso-hansi-font-family:Cambria; mso-hansi-theme-font:minor-latin;} Friday October 26th the Microsoft Surface RT arrived at the office.  I was summoned to my boss’s office for the grand unpacking.  If I had planned ahead I could have used my iPhone 4 to film the event and post it on YouTube however the desire to hold the device and turn it ON was more inviting than becoming a proxy reviewer for Engadget’s website.  1980 was the first time we had a personal computer in our house.  It was a  Kaypro computer. It weighed 29 pounds more than any persons lap could hold.  Then the term “portable computer” meant you could remove it from the building and take it else where.  Today I am typing on this entry on a Macbook Air which weighs 2.38 pounds. This morning Amazons front page main title is: “Much More for Much Less” I was born at the right time to start with the CPM operating system on the Kaypro thru the DOS, Windows, Linux, Mac OSX and mobile phone operating systems and languages.  If you are not aware Technology is moving at a rapid pace.  The New iPad (those who are keeping score – iPad4) is replacing a 7 month old machine the New iPad (iPad 3) I have used and owned many technology devices in my life.  The main point that most of the reader who are in the USA overlook is the fact that we are in the USA.  The devices we purchase have a great digital garden to support them.  The Kaypro computer had a 7-inch screen.  It was a TV tube with two colors – Black and Green.  You could see the 80-column screen flicker with characters – have you every played Pac-Man emulated on the screen with the ABC characters. Traveling across the world you will find that not all apps on your device will function as they did back home because they are not offered outside of your country of origin. I think the main question a buyer of technology should be asking is Function.  The greatest Specs with out function limit you.  The most beautiful form with out function is the same as a crystal vase on your shelf – not a good cereal bowl in the morning. Microsoft Surface RT, Amazon Kindle Fire and Apple iPad all great devices in their respective customers hands. My advice for those looking to purchase on this year:  If the device is your only technology device you buy what you WANT and LIKE. Consider this parallel universe if its not your only device?  Ever go shopping for clothing, shoes, and accessories with your wife, girlfriend, sister or mother?  If you listen carefully you will hear the little voices coming out of there heads saying:  “This goes well with that and I can use it also with that outfit” ”Do you think this clashes with that?”  “Ohh I love how that combination looks on you”.  Portable devices such as tablets and computers can offer a whole lot more when they are combined with the digital echo system you have at home and the manufacturer offers online. Pros of each Device: Microsoft Surface RT: There is a new functionality named SmartGlass which will let you share the content off your tablet to your XBOX 360.  Microsoft office is loaded on the tablet.  You can have more than one user profile on the tablet if you share it with others.   Amazon Kindle or Kindle HD: If you are an Amazon consumer with an annual Amazon Prime service you can consume videos and read books off the Amazon site.  Its the cheapest device.  Its a step up from the kindle reader in many ways.   Apple Ipad or Ipad mini: Over 270 Thousand applications.  Airplay permits you the ability to share to your TV screen. If you are a cord cutter (a person who gets their entertainment content over the web or air vs Cable Providers) the Airplay or Smart glass are a huge bonus.  iPad mini or not: The mini will fit in a purse where the larger one will not.  Its lighter which makes it nice to hold for prolonged periods.  It has an option for LTE wireless which non of the other sub 9 inch tables offer.  The screen is non retina which means the applications are smaller.  Speaking with individuals who are above 50 in age that wear glasses they retina does not make a difference for them however they prefer the larger iPad over the new mini.   Happy Shopping this Channuka Season.   The Kosher Coder.   Follow me on twitter @KosherCoder

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• Not getting desired results with SSAO implementation

  - by user1294203

  After having implemented deferred rendering, I tried my luck with a SSAO implementation using this Tutorial. Unfortunately, I'm not getting anything that looks like SSAO, you can see my result below. You can see there is some weird pattern forming and there is no occlusion shading where there needs to be (i.e. in between the objects and on the ground). The shaders I implemented follow: #VS #version 330 core uniform mat4 invProjMatrix; layout(location = 0) in vec3 in_Position; layout(location = 2) in vec2 in_TexCoord; noperspective out vec2 pass_TexCoord; smooth out vec3 viewRay; void main(void){ pass_TexCoord = in_TexCoord; viewRay = (invProjMatrix * vec4(in_Position, 1.0)).xyz; gl_Position = vec4(in_Position, 1.0); } #FS #version 330 core uniform sampler2D DepthMap; uniform sampler2D NormalMap; uniform sampler2D noise; uniform vec2 projAB; uniform ivec3 noiseScale_kernelSize; uniform vec3 kernel[16]; uniform float RADIUS; uniform mat4 projectionMatrix; noperspective in vec2 pass_TexCoord; smooth in vec3 viewRay; layout(location = 0) out float out_AO; vec3 CalcPosition(void){ float depth = texture(DepthMap, pass_TexCoord).r; float linearDepth = projAB.y / (depth - projAB.x); vec3 ray = normalize(viewRay); ray = ray / ray.z; return linearDepth * ray; } mat3 CalcRMatrix(vec3 normal, vec2 texcoord){ ivec2 noiseScale = noiseScale_kernelSize.xy; vec3 rvec = texture(noise, texcoord * noiseScale).xyz; vec3 tangent = normalize(rvec - normal * dot(rvec, normal)); vec3 bitangent = cross(normal, tangent); return mat3(tangent, bitangent, normal); } void main(void){ vec2 TexCoord = pass_TexCoord; vec3 Position = CalcPosition(); vec3 Normal = normalize(texture(NormalMap, TexCoord).xyz); mat3 RotationMatrix = CalcRMatrix(Normal, TexCoord); int kernelSize = noiseScale_kernelSize.z; float occlusion = 0.0; for(int i = 0; i < kernelSize; i++){ // Get sample position vec3 sample = RotationMatrix * kernel[i]; sample = sample * RADIUS + Position; // Project and bias sample position to get its texture coordinates vec4 offset = projectionMatrix * vec4(sample, 1.0); offset.xy /= offset.w; offset.xy = offset.xy * 0.5 + 0.5; // Get sample depth float sample_depth = texture(DepthMap, offset.xy).r; float linearDepth = projAB.y / (sample_depth - projAB.x); if(abs(Position.z - linearDepth ) < RADIUS){ occlusion += (linearDepth <= sample.z) ? 1.0 : 0.0; } } out_AO = 1.0 - (occlusion / kernelSize); } I draw a full screen quad and pass Depth and Normal textures. Normals are in RGBA16F with the alpha channel reserved for the AO factor in the blur pass. I store depth in a non linear Depth buffer (32F) and recover the linear depth using: float linearDepth = projAB.y / (depth - projAB.x); where projAB.y is calculated as: and projAB.x as: These are derived from the glm::perspective(gluperspective) matrix. z_n and z_f are the near and far clip distance. As described in the link I posted on the top, the method creates samples in a hemisphere with higher distribution close to the center. It then uses random vectors from a texture to rotate the hemisphere randomly around the Z direction and finally orients it along the normal at the given pixel. Since the result is noisy, a blur pass follows the SSAO pass. Anyway, my position reconstruction doesn't seem to be wrong since I also tried doing the same but with the position passed from a texture instead of being reconstructed. I also tried playing with the Radius, noise texture size and number of samples and with different kinds of texture formats, with no luck. For some reason when changing the Radius, nothing changes. Does anyone have any suggestions? What could be going wrong?

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• Stumbling Through: Visual Studio 2010 (Part II)

  I would now like to expand a little on what I stumbled through in part I of my Visual Studio 2010 post and touch on a few other features of VS 2010.  Specifically, I want to generate some code based off of an Entity Framework model and tie it up to an actual data source.  Im not going to take the easy way and tie to a SQL Server data source, though, I will tie it to an XML data file instead.  Why?  Well, why not?  This is purely for learning, there are probably much better ways to get strongly-typed classes around XML but it will force us to go down a path less travelled and maybe learn a few things along the way.  Once we get this XML data and the means to interact with it, I will revisit data binding to this data in a WPF form and see if I cant get reading, adding, deleting, and updating working smoothly with minimal code.  To begin, I will use what was learned in the first part of this blog topic and draw out a data model for the MFL (My Football League) - I dont want the NFL to come down and sue me for using their name in this totally football-related article.  The data model looks as follows, with Teams having Players, and Players having a position and statistics for each season they played: Note that when making the associations between these entities, I was given the option to create the foreign key but I only chose to select this option for the association between Player and Position.  The reason for this is that I am picturing the XML that will contain this data to look somewhat like this: <MFL> <Position/> <Position/> <Position/> <Team>     <Player>         <Statistic/>     </Player> </Team> </MFL> Statistic will be under its associated Player node, and Player will be under its associated Team node no need to have an Id to reference it if we know it will always fall under its parent.  Position, however, is more of a lookup value that will not have any hierarchical relationship to the player.  In fact, the Position data itself may be in a completely different xml file (something Id like to play around with), so in any case, a player will need to reference the position by its Id. So now that we have a simple data model laid out, I would like to generate two things based on it:  A class for each entity with properties corresponding to each entity property An IO class with methods to get data for each entity, either all instances, by Id or by parent. Now my experience with code generation in the past has consisted of writing up little apps that use the code dom directly to regenerate code on demand (or using tools like CodeSmith).  Surely, there has got to be a more fun way to do this given that we are using the Entity Framework which already has built-in code generation for SQL Server support.  Lets start with that built-in stuff to give us a base to work off of.  Right click anywhere in the canvas of our model and select Add Code Generation Item: So just adding that code item seemed to do quite a bit towards what I was intending: It apparently generated a class for each entity, but also a whole ton more.  I mean a TON more.  Way too much complicated code was generated now that code is likely to be a black box anyway so it shouldnt matter, but we need to understand how to make this work the way we want it to work, so lets get ready to do some stumbling through that text template (tt) file. When I open the .tt file that was generated, right off the bat I realize there is going to be trouble there is no color coding, no intellisense no nothing!  That is going to make stumbling through more like groping blindly in the dark while handcuffed and hopping on one foot, which was one of the alternate titles I was considering for this blog.  Thankfully, the community comes to my rescue and I wont have to cast my mind back to the glory days of coding in VI (look it up, kids).  Using the Extension Manager (Available under the Tools menu), I did a quick search for tt editor in the Online Gallery and quickly found the Tangible T4 Editor: Downloading and installing this was a breeze, and after doing so I got some color coding and intellisense while editing the tt files.  If you will be doing any customizing of tt files, I highly recommend installing this extension.  Next, well see if that is enough help for us to tweak that tt file to do the kind of code generation that we wantDid 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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• Computer Networks UNISA - Chap 8 &ndash; Wireless Networking

  - by MarkPearl

  After reading this section you should be able to Explain how nodes exchange wireless signals Identify potential obstacles to successful transmission and their repercussions, such as interference and reflection Understand WLAN architecture Specify the characteristics of popular WLAN transmission methods including 802.11 a/b/g/n Install and configure wireless access points and their clients Describe wireless MAN and WAN technologies, including 802.16 and satellite communications The Wireless Spectrum All wireless signals are carried through the air by electromagnetic waves. The wireless spectrum is a continuum of the electromagnetic waves used for data and voice communication. The wireless spectrum falls between 9KHZ and 300 GHZ. Characteristics of Wireless Transmission Antennas Each type of wireless service requires an antenna specifically designed for that service. The service’s specification determine the antenna’s power output, frequency, and radiation pattern. A directional antenna issues wireless signals along a single direction. An omnidirectional antenna issues and receives wireless signals with equal strength and clarity in all directions The geographical area that an antenna or wireless system can reach is known as its range Signal Propagation LOS (line of sight) uses the least amount of energy and results in the reception of the clearest possible signal. When there is an obstacle in the way, the signal may… pass through the object or be obsrobed by the object or may be subject to reflection, diffraction or scattering. Reflection – waves encounter an object and bounces off it. Diffraction – signal splits into secondary waves when it encounters an obstruction Scattering – is the diffusion or the reflection in multiple different directions of a signal Signal Degradation Fading occurs as a signal hits various objects. Because of fading, the strength of the signal that reaches the receiver is lower than the transmitted signal strength. The further a signal moves from its source, the weaker it gets (this is called attenuation) Signals are also affected by noise – the electromagnetic interference) Interference can distort and weaken a wireless signal in the same way that noise distorts and weakens a wired signal. Frequency Ranges Older wireless devices used the 2.4 GHZ band to send and receive signals. This had 11 communication channels that are unlicensed. Newer wireless devices can also use the 5 GHZ band which has 24 unlicensed bands Narrowband, Broadband, and Spread Spectrum Signals Narrowband – a transmitter concentrates the signal energy at a single frequency or in a very small range of frequencies Broadband – uses a relatively wide band of the wireless spectrum and offers higher throughputs than narrowband technologies The use of multiple frequencies to transmit a signal is known as spread-spectrum technology. In other words a signal never stays continuously within one frequency range during its transmission. One specific implementation of spread spectrum is FHSS (frequency hoping spread spectrum). Another type is known as DSS (direct sequence spread spectrum) Fixed vs. Mobile Each type of wireless communication falls into one of two categories Fixed – the location of the transmitted and receiver do not move (results in energy saved because weaker signal strength is possible with directional antennas) Mobile – the location can change WLAN (Wireless LAN) Architecture There are two main types of arrangements Adhoc – data is sent directly between devices – good for small local devices Infrastructure mode – a wireless access point is placed centrally, that all devices connect with 802.11 WLANs The most popular wireless standards used on contemporary LANs are those developed by IEEE’s 802.11 committee. Over the years several distinct standards related to wireless networking have been released. Four of the best known standards are also referred to as Wi-Fi. They are…. 802.11b 802.11a 802.11g 802.11n These four standards share many characteristics. i.e. All 4 use half duplex signalling Follow the same access method Access Method 802.11 standards specify the use of CSMA/CA (Carrier Sense Multiple Access with Collision Avoidance) to access a shared medium. Using CSMA/CA before a station begins to send data on an 802.11 network, it checks for existing wireless transmissions. If the source node detects no transmission activity on the network, it waits a brief period of time and then sends its transmission. If the source does detect activity, it waits a brief period of time before checking again. The destination node receives the transmission and, after verifying its accuracy, issues an acknowledgement (ACT) packet to the source. If the source receives the ACK it assumes the transmission was successful, – if it does not receive an ACK it assumes the transmission failed and sends it again. Association Two types of scanning… Active – station transmits a special frame, known as a prove, on all available channels within its frequency range. When an access point finds the probe frame, it issues a probe response. Passive – wireless station listens on all channels within its frequency range for a special signal, known as a beacon frame, issued from an access point – the beacon frame contains information necessary to connect to the point. Re-association occurs when a mobile user moves out of one access point’s range and into the range of another. Frames Read page 378 – 381 about frames and specific 802.11 protocols Bluetooth Networks Sony Ericson originally invented the Bluetooth technology in the early 1990s. In 1998 other manufacturers joined Ericsson in the Special Interest Group (SIG) whose aim was to refine and standardize the technology. Bluetooth was designed to be used on small networks composed of personal communications devices. It has become popular wireless technology for communicating among cellular telephones, phone headsets, etc. Wireless WANs and Internet Access Refer to pages 396 – 402 of the textbook for details.

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• Data management in unexpected places

  - by Ashok_Ora

  Normal 0 false false false EN-US X-NONE X-NONE Data management in unexpected places When you think of network switches, routers, firewall appliances, etc., it may not be obvious that at the heart of these kinds of solutions is an engine that can manage huge amounts of data at very high throughput with low latencies and high availability. Consider a network router that is processing tens (or hundreds) of thousands of network packets per second. So what really happens inside a router? Packets are streaming in at the rate of tens of thousands per second. Each packet has multiple attributes, for example, a destination, associated SLAs etc. For each packet, the router has to determine the address of the next “hop” to the destination; it has to determine how to prioritize this packet. If it’s a high priority packet, then it has to be sent on its way before lower priority packets. As a consequence of prioritizing high priority packets, lower priority data packets may need to be temporarily stored (held back), but addressed fairly. If there are security or privacy requirements associated with the data packet, those have to be enforced. You probably need to keep track of statistics related to the packets processed (someone’s sure to ask). You have to do all this (and more) while preserving high availability i.e. if one of the processors in the router goes down, you have to have a way to continue processing without interruption (the customer won’t be happy with a “choppy” VoIP conversation, right?). And all this has to be achieved without ANY intervention from a human operator – the router is most likely to be in a remote location – it must JUST CONTINUE TO WORK CORRECTLY, even when bad things happen. How is this implemented? As soon as a packet arrives, it is interpreted by the receiving software. The software decodes the packet headers in order to determine the destination, kind of packet (e.g. voice vs. data), SLAs associated with the “owner” of the packet etc. It looks up the internal database of “rules” of how to process this packet and handles the packet accordingly. The software might choose to hold on to the packet safely for some period of time, if it’s a low priority packet. Ah – this sounds very much like a database problem. For each packet, you have to minimally · Look up the most efficient next “hop” towards the destination. The “most efficient” next hop can change, depending on latency, availability etc. · Look up the SLA and determine the priority of this packet (e.g. voice calls get priority over data ftp) · Look up security information associated with this data packet. It may be necessary to retrieve the context for this network packet since a network packet is a small “slice” of a session. The context for the “header” packet needs to be stored in the router, in order to make this work. · If the priority of the packet is low, then “store” the packet temporarily in the router until it is time to forward the packet to the next hop. · Update various statistics about the packet. In most cases, you have to do all this in the context of a single transaction. For example, you want to look up the forwarding address and perform the “send” in a single transaction so that the forwarding address doesn’t change while you’re sending the packet. So, how do you do all this? Berkeley DB is a proven, reliable, high performance, highly available embeddable database, designed for exactly these kinds of usage scenarios. Berkeley DB is a robust, reliable, proven solution that is currently being used in these scenarios. First and foremost, Berkeley DB (or BDB for short) is very very fast. It can process tens or hundreds of thousands of transactions per second. It can be used as a pure in-memory database, or as a disk-persistent database. BDB provides high availability – if one board in the router fails, the system can automatically failover to another board – no manual intervention required. BDB is self-administering – there’s no need for manual intervention in order to maintain a BDB application. No need to send a technician to a remote site in the middle of nowhere on a freezing winter day to perform maintenance operations. BDB is used in over 200 million deployments worldwide for the past two decades for mission-critical applications such as the one described here. You have a choice of spending valuable resources to implement similar functionality, or, you could simply embed BDB in your application and off you go! I know what I’d do – choose BDB, so I can focus on my business problem. What will you do? /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin-top:0in; mso-para-margin-right:0in; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0in; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin;}

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• Upgrading to Code Based Migrations EF 4.3.1 with Connector/Net 6.6

  - by GABMARTINEZ

  Entity Framework 4.3.1 includes a new feature called code first migrations.  We are adding support for this feature in our upcoming 6.6 release of Connector/Net.  In this walk-through we'll see the workflow of code-based migrations when you have an existing application and you would like to upgrade to this EF 4.3.1 version and use this approach, so you can keep track of the changes that you do to your database.   The first thing we need to do is add the new Entity Framework 4.3.1 package to our application. This should via the NuGet package manager.  You can read more about why EF is not part of the .NET framework here. Adding EF 4.3.1 to our existing application  Inside VS 2010 go to Tools -> Library Package Manager -> Package Manager Console, this will open the Power Shell Host Window where we can work with all the EF commands. In order to install this library to your existing application you should type Install-Package EntityFramework This will make some changes to your application. So Let's check them. In your .config file you'll see a  <configSections> which contains the version you have from EntityFramework and also was added the <entityFramework> section as shown below. This section is by default configured to use SQL Express which won't be necesary for this case. So you can comment it out or leave it empty. Also please make sure you're using the Connector/Net 6.6.x version which is the one that has this support as is shown in the previous image. At this point we face one issue; in order to be able to work with Migrations we need the __MigrationHistory table that we don't have yet since our Database was created with an older version. This table is used to keep track of the changes in our model. So we need to get it in our existing Database. Getting a Migration-History table into an existing database First thing we need to do to enable migrations in our existing application is to create our configuration class which will set up the MySqlClient Provider as our SQL Generator. So we have to add it with the following code: using System.Data.Entity.Migrations;     //add this at the top of your cs file public class Configuration : DbMigrationsConfiguration<NameOfYourDbContext>  //Make sure to use the name of your existing DBContext { public Configuration() { this.AutomaticMigrationsEnabled = false; //Set Automatic migrations to false since we'll be applying the migrations manually for this case. SetSqlGenerator("MySql.Data.MySqlClient", new MySql.Data.Entity.MySqlMigrationSqlGenerator());     }   }  This code will set up our configuration that we'll be using when executing all the migrations for our application. Once we have done this we can Build our application so we can check that everything is fine. Creating our Initial Migration Now let's add our Initial Migration. In Package Manager Console, execute "add-migration InitialCreate", you can use any other name but I like to set this as our initial create for future reference. After we run this command, some changes were done in our application: A new Migrations Folder was created. A new class migration call InitialCreate which in most of the cases should have empty Up and Down methods as long as your database is up to date with your Model. Since all your entities already exists, delete all duplicated code to create any entity which exists already in your Database if there is any. I found this easier when you don't have any pending updates to do to your database. Now we have our empty migration that will make no changes in our database and represents how are all the things at the begining of our migrations.  Finally, let's create our MigrationsHistory table. Optionally you can add SQL code to delete the edmdata table which is not needed anymore. public override void Up() { // Just make sure that you used 4.1 or later version         Sql("DROP TABLE EdmMetadata"); } From our Package Manager Console let's type: Update-database; If you like to see the operations made on each Update-database command you can use the flag -verbose after the Update-database. This will make two important changes.  It will execute the Up method in the initial migration which has no changes in the database. And second, and very important,  it will create the __MigrationHistory table necessary to keep track of your changes. And next time you make a change to your database it will compare the current model to the one stored in the Model Column of this table. Conclusion The important thing of this walk through is that we must create our initial migration before we start doing any changes to our model. This way we'll be adding the necessary __MigrationsHistory table to our existing database, so we can keep our database up to date with all the changes we do in our context model using migrations. Hope you have found this information useful. Please let us know if you have any questions or comments, also please check our forums here where we keep answering questions in general for the community.  Happy MySQL/Net Coding!

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• Oracle NoSQL Database Exceeds 1 Million Mixed YCSB Ops/Sec

  - by Charles Lamb

  We ran a set of YCSB performance tests on Oracle NoSQL Database using SSD cards and Intel Xeon E5-2690 CPUs with the goal of achieving 1M mixed ops/sec on a 95% read / 5% update workload. We used the standard YCSB parameters: 13 byte keys and 1KB data size (1,102 bytes after serialization). The maximum database size was 2 billion records, or approximately 2 TB of data. We sized the shards to ensure that this was not an "in-memory" test (i.e. the data portion of the B-Trees did not fit into memory). All updates were durable and used the "simple majority" replica ack policy, effectively 'committing to the network'. All read operations used the Consistency.NONE_REQUIRED parameter allowing reads to be performed on any replica. In the past we have achieved 100K ops/sec using SSD cards on a single shard cluster (replication factor 3) so for this test we used 10 shards on 15 Storage Nodes with each SN carrying 2 Rep Nodes and each RN assigned to its own SSD card. After correcting a scaling problem in YCSB, we blew past the 1M ops/sec mark with 8 shards and proceeded to hit 1.2M ops/sec with 10 shards.  Hardware Configuration We used 15 servers, each configured with two 335 GB SSD cards. We did not have homogeneous CPUs across all 15 servers available to us so 12 of the 15 were Xeon E5-2690, 2.9 GHz, 2 sockets, 32 threads, 193 GB RAM, and the other 3 were Xeon E5-2680, 2.7 GHz, 2 sockets, 32 threads, 193 GB RAM.  There might have been some upside in having all 15 machines configured with the faster CPU, but since CPU was not the limiting factor we don't believe the improvement would be significant. The client machines were Xeon X5670, 2.93 GHz, 2 sockets, 24 threads, 96 GB RAM. Although the clients had 96 GB of RAM, neither the NoSQL Database or YCSB clients require anywhere near that amount of memory and the test could have just easily been run with much less. Networking was all 10GigE. YCSB Scaling Problem We made three modifications to the YCSB benchmark. The first was to allow the test to accommodate more than 2 billion records (effectively int's vs long's). To keep the key size constant, we changed the code to use base 32 for the user ids. The second change involved to the way we run the YCSB client in order to make the test itself horizontally scalable.The basic problem has to do with the way the YCSB test creates its Zipfian distribution of keys which is intended to model "real" loads by generating clusters of key collisions. Unfortunately, the percentage of collisions on the most contentious keys remains the same even as the number of keys in the database increases. As we scale up the load, the number of collisions on those keys increases as well, eventually exceeding the capacity of the single server used for a given key.This is not a workload that is realistic or amenable to horizontal scaling. YCSB does provide alternate key distribution algorithms so this is not a shortcoming of YCSB in general. We decided that a better model would be for the key collisions to be limited to a given YCSB client process. That way, as additional YCSB client processes (i.e. additional load) are added, they each maintain the same number of collisions they encounter themselves, but do not increase the number of collisions on a single key in the entire store. We added client processes proportionally to the number of records in the database (and therefore the number of shards). This change to the use of YCSB better models a use case where new groups of users are likely to access either just their own entries, or entries within their own subgroups, rather than all users showing the same interest in a single global collection of keys. If an application finds every user having the same likelihood of wanting to modify a single global key, that application has no real hope of getting horizontal scaling. Finally, we used read/modify/write (also known as "Compare And Set") style updates during the mixed phase. This uses versioned operations to make sure that no updates are lost. This mode of operation provides better application behavior than the way we have typically run YCSB in the past, and is only practical at scale because we eliminated the shared key collision hotspots.It is also a more realistic testing scenario. To reiterate, all updates used a simple majority replica ack policy making them durable. Scalability Results In the table below, the "KVS Size" column is the number of records with the number of shards and the replication factor. Hence, the first row indicates 400m total records in the NoSQL Database (KV Store), 2 shards, and a replication factor of 3. The "Clients" column indicates the number of YCSB client processes. "Threads" is the number of threads per process with the total number of threads. Hence, 90 threads per YCSB process for a total of 360 threads. The client processes were distributed across 10 client machines. Shards KVS Size Clients Mixed (records) Threads OverallThroughput(ops/sec) Read Latencyav/95%/99%(ms) Write Latencyav/95%/99%(ms) 2 400m(2x3) 4 90(360) 302,152 0.76/1/3 3.08/8/35 4 800m(4x3) 8 90(720) 558,569 0.79/1/4 3.82/16/45 8 1600m(8x3) 16 90(1440) 1,028,868 0.85/2/5 4.29/21/51 10 2000m(10x3) 20 90(1800) 1,244,550 0.88/2/6 4.47/23/53

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