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  • Big Data – Role of Cloud Computing in Big Data – Day 11 of 21

    - by Pinal Dave
    In yesterday’s blog post we learned the importance of the NewSQL. In this article we will understand the role of Cloud in Big Data Story What is Cloud? Cloud is the biggest buzzword around from last few years. Everyone knows about the Cloud and it is extremely well defined online. In this article we will discuss cloud in the context of the Big Data. Cloud computing is a method of providing a shared computing resources to the application which requires dynamic resources. These resources include applications, computing, storage, networking, development and various deployment platforms. The fundamentals of the cloud computing are that it shares pretty much share all the resources and deliver to end users as a service.  Examples of the Cloud Computing and Big Data are Google and Amazon.com. Both have fantastic Big Data offering with the help of the cloud. We will discuss this later in this blog post. There are two different Cloud Deployment Models: 1) The Public Cloud and 2) The Private Cloud Public Cloud Public Cloud is the cloud infrastructure build by commercial providers (Amazon, Rackspace etc.) creates a highly scalable data center that hides the complex infrastructure from the consumer and provides various services. Private Cloud Private Cloud is the cloud infrastructure build by a single organization where they are managing highly scalable data center internally. Here is the quick comparison between Public Cloud and Private Cloud from Wikipedia:   Public Cloud Private Cloud Initial cost Typically zero Typically high Running cost Unpredictable Unpredictable Customization Impossible Possible Privacy No (Host has access to the data Yes Single sign-on Impossible Possible Scaling up Easy while within defined limits Laborious but no limits Hybrid Cloud Hybrid Cloud is the cloud infrastructure build with the composition of two or more clouds like public and private cloud. Hybrid cloud gives best of the both the world as it combines multiple cloud deployment models together. Cloud and Big Data – Common Characteristics There are many characteristics of the Cloud Architecture and Cloud Computing which are also essentially important for Big Data as well. They highly overlap and at many places it just makes sense to use the power of both the architecture and build a highly scalable framework. Here is the list of all the characteristics of cloud computing important in Big Data Scalability Elasticity Ad-hoc Resource Pooling Low Cost to Setup Infastructure Pay on Use or Pay as you Go Highly Available Leading Big Data Cloud Providers There are many players in Big Data Cloud but we will list a few of the known players in this list. Amazon Amazon is arguably the most popular Infrastructure as a Service (IaaS) provider. The history of how Amazon started in this business is very interesting. They started out with a massive infrastructure to support their own business. Gradually they figured out that their own resources are underutilized most of the time. They decided to get the maximum out of the resources they have and hence  they launched their Amazon Elastic Compute Cloud (Amazon EC2) service in 2006. Their products have evolved a lot recently and now it is one of their primary business besides their retail selling. Amazon also offers Big Data services understand Amazon Web Services. Here is the list of the included services: Amazon Elastic MapReduce – It processes very high volumes of data Amazon DynammoDB – It is fully managed NoSQL (Not Only SQL) database service Amazon Simple Storage Services (S3) – A web-scale service designed to store and accommodate any amount of data Amazon High Performance Computing – It provides low-tenancy tuned high performance computing cluster Amazon RedShift – It is petabyte scale data warehousing service Google Though Google is known for Search Engine, we all know that it is much more than that. Google Compute Engine – It offers secure, flexible computing from energy efficient data centers Google Big Query – It allows SQL-like queries to run against large datasets Google Prediction API – It is a cloud based machine learning tool Other Players Besides Amazon and Google we also have other players in the Big Data market as well. Microsoft is also attempting Big Data with the Cloud with Microsoft Azure. Additionally Rackspace and NASA together have initiated OpenStack. The goal of Openstack is to provide a massively scaled, multitenant cloud that can run on any hardware. Thing to Watch The cloud based solutions provides a great integration with the Big Data’s story as well it is very economical to implement as well. However, there are few things one should be very careful when deploying Big Data on cloud solutions. Here is a list of a few things to watch: Data Integrity Initial Cost Recurring Cost Performance Data Access Security Location Compliance Every company have different approaches to Big Data and have different rules and regulations. Based on various factors, one can implement their own custom Big Data solution on a cloud. Tomorrow In tomorrow’s blog post we will discuss about various Operational Databases supporting Big Data. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: Big Data, PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL

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  • And the Winners of Fusion Middleware Innovation Awards in Data Integration are…

    - by Irem Radzik
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Raymond James and Morrison Supermarkets were selected for the data integration category for their innovative use of Oracle’s data integration products and the great results they have achieved. In this blog I would like to briefly introduce you to these award winning projects. Raymond James is a diversified financial services company, which provides financial planning, wealth management, investment banking, and asset management. They are using Oracle GoldenGate and Oracle Data Integrator to feed their operational data store (ODS), which supports application services across the enterprise. A major requirement for their project was low data latency, as key decisions are made based on the data in the ODS. They were able to fulfill this requirement due to the Oracle Data Integrator’s integrated solution with Oracle GoldenGate. Oracle GoldenGate captures changed data from different systems including Oracle Database, HP NonStop and Microsoft SQL Server into a single data store on SQL Server 2008. Oracle Data Integrator provides data transformations for the ODS. Leveraging ODI’s integration with GoldenGate, Raymond James now sees a 9 second median latency (from source commit to ODS target commit). The ODS solution delivers high quality, accurate data for consuming applications such as Raymond James’ next generation client and portfolio management systems as well as real-time operational reporting. It enables timely information for making better decisions. There are more benefits Raymond James achieved with this implementation of Oracle’s data integration solution. The software developers and architects of this solution, Tim Garrod and Ryan Fonnett, have told us during their presentation at OpenWorld that they also reduced application complexity significantly while improving developer productivity through trusted operational services. They were able to utilize CDC to generate alerts for business users, and for applications (for example for cache hydration mechanisms). One cool innovation example among many in this project is that using ODI's flexible architecture, Tim and Ryan could build 24/7 self-healing processes. And these processes have hardly failed. Integration processes fixes the errors itself. Pretty amazing; and a great solution for environments that need such reliability and availability. (You can see Tim and Ryan’s photo with the Innovation Award above.) The other winner of this year in the data integration category, Morrison Supermarkets, is the UK’s 4th largest grocery retailer. The company has been migrating all their legacy applications on to a new-world application set based on Oracle and consolidating all BI on to a single Oracle platform. The company recently implemented Oracle Exadata as the data warehouse engine and uses Oracle Business Intelligence EE. Their goal with deploying GoldenGate and ODI was to provide BI data to the enterprise in a way that it also supports operational decision making requirements from a wide range of Oracle based ERP applications such as E-Business Suite, PeopleSoft, Oracle Retail Suite. They use GoldenGate’s log-based change data capture capabilities and Oracle Data Integrator to populate the Oracle Retail Data Model. The electronic point of sale (EPOS) integration solution they built processes over 80 million transactions/day at busy periods in near real time (15 mins). It provides valuable insight to Retail and Commercial teams for both intra-day and historical trend analysis. As I mentioned in yesterday’s blog, the right data integration platform can transform the business. Here is another example: The point-of-sale integration enabled the grocery chain to optimize its stock management, leading to another award: Morrisons won the Grocer 33 award in 2012 - beating all other major UK supermarkets in product availability. Congratulations, Morrisons,on another award! Celebrating the innovation and the success of our customers with Oracle’s data integration products was definitely a highlight of Oracle OpenWorld for me. I look forward to hearing more from Raymond James, Morrisons, and the other customers that presented their data integration projects at OpenWorld, on how they are creating more value for their organizations.

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  • World Record Oracle Business Intelligence Benchmark on SPARC T4-4

    - by Brian
    Oracle's SPARC T4-4 server configured with four SPARC T4 3.0 GHz processors delivered the first and best performance of 25,000 concurrent users on Oracle Business Intelligence Enterprise Edition (BI EE) 11g benchmark using Oracle Database 11g Release 2 running on Oracle Solaris 10. A SPARC T4-4 server running Oracle Business Intelligence Enterprise Edition 11g achieved 25,000 concurrent users with an average response time of 0.36 seconds with Oracle BI server cache set to ON. The benchmark data clearly shows that the underlying hardware, SPARC T4 server, and the Oracle BI EE 11g (11.1.1.6.0 64-bit) platform scales within a single system supporting 25,000 concurrent users while executing 415 transactions/sec. The benchmark demonstrated the scalability of Oracle Business Intelligence Enterprise Edition 11g 11.1.1.6.0, which was deployed in a vertical scale-out fashion on a single SPARC T4-4 server. Oracle Internet Directory configured on SPARC T4 server provided authentication for the 25,000 Oracle BI EE users with sub-second response time. A SPARC T4-4 with internal Solid State Drive (SSD) using the ZFS file system showed significant I/O performance improvement over traditional disk for the Web Catalog activity. In addition, ZFS helped get past the UFS limitation of 32767 sub-directories in a Web Catalog directory. The multi-threaded 64-bit Oracle Business Intelligence Enterprise Edition 11g and SPARC T4-4 server proved to be a successful combination by providing sub-second response times for the end user transactions, consuming only half of the available CPU resources at 25,000 concurrent users, leaving plenty of head room for increased load. The Oracle Business Intelligence on SPARC T4-4 server benchmark results demonstrate that comprehensive BI functionality built on a unified infrastructure with a unified business model yields best-in-class scalability, reliability and performance. Oracle BI EE 11g is a newer version of Business Intelligence Suite with richer and superior functionality. Results produced with Oracle BI EE 11g benchmark are not comparable to results with Oracle BI EE 10g benchmark. Oracle BI EE 11g is a more difficult benchmark to run, exercising more features of Oracle BI. Performance Landscape Results for the Oracle BI EE 11g version of the benchmark. Results are not comparable to the Oracle BI EE 10g version of the benchmark. Oracle BI EE 11g Benchmark System Number of Users Response Time (sec) 1 x SPARC T4-4 (4 x SPARC T4 3.0 GHz) 25,000 0.36 Results for the Oracle BI EE 10g version of the benchmark. Results are not comparable to the Oracle BI EE 11g version of the benchmark. Oracle BI EE 10g Benchmark System Number of Users 2 x SPARC T5440 (4 x SPARC T2+ 1.6 GHz) 50,000 1 x SPARC T5440 (4 x SPARC T2+ 1.6 GHz) 28,000 Configuration Summary Hardware Configuration: SPARC T4-4 server 4 x SPARC T4-4 processors, 3.0 GHz 128 GB memory 4 x 300 GB internal SSD Storage Configuration: "> Sun ZFS Storage 7120 16 x 146 GB disks Software Configuration: Oracle Solaris 10 8/11 Oracle Solaris Studio 12.1 Oracle Business Intelligence Enterprise Edition 11g (11.1.1.6.0) Oracle WebLogic Server 10.3.5 Oracle Internet Directory 11.1.1.6.0 Oracle Database 11g Release 2 Benchmark Description Oracle Business Intelligence Enterprise Edition (Oracle BI EE) delivers a robust set of reporting, ad-hoc query and analysis, OLAP, dashboard, and scorecard functionality with a rich end-user experience that includes visualization, collaboration, and more. The Oracle BI EE benchmark test used five different business user roles - Marketing Executive, Sales Representative, Sales Manager, Sales Vice-President, and Service Manager. These roles included a maximum of 5 different pre-built dashboards. Each dashboard page had an average of 5 reports in the form of a mix of charts, tables and pivot tables, returning anywhere from 50 rows to approximately 500 rows of aggregated data. The test scenario also included drill-down into multiple levels from a table or chart within a dashboard. The benchmark test scenario uses a typical business user sequence of dashboard navigation, report viewing, and drill down. For example, a Service Manager logs into the system and navigates to his own set of dashboards using Service Manager. The BI user selects the Service Effectiveness dashboard, which shows him four distinct reports, Service Request Trend, First Time Fix Rate, Activity Problem Areas, and Cost Per Completed Service Call spanning 2002 to 2005. The user then proceeds to view the Customer Satisfaction dashboard, which also contains a set of 4 related reports, drills down on some of the reports to see the detail data. The BI user continues to view more dashboards – Customer Satisfaction and Service Request Overview, for example. After navigating through those dashboards, the user logs out of the application. The benchmark test is executed against a full production version of the Oracle Business Intelligence 11g Applications with a fully populated underlying database schema. The business processes in the test scenario closely represent a real world customer scenario. See Also SPARC T4-4 Server oracle.com OTN Oracle Business Intelligence oracle.com OTN Oracle Database 11g Release 2 Enterprise Edition oracle.com OTN WebLogic Suite oracle.com OTN Oracle Solaris oracle.com OTN Disclosure Statement Copyright 2012, Oracle and/or its affiliates. All rights reserved. Oracle and Java are registered trademarks of Oracle and/or its affiliates. Other names may be trademarks of their respective owners. Results as of 30 September 2012.

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  • Connection Pooling is Busted

    - by MightyZot
    A few weeks ago we started getting complaints about performance in an application that has performed very well for many years.  The application is a n-tier application that uses ADODB with the SQLOLEDB provider to talk to a SQL Server database.  Our object model is written in such a way that each public method validates security before performing requested actions, so there is a significant number of queries executed to get information about file cabinets, retrieve images, create workflows, etc.  (PaperWise is a document management and workflow system.)  A common factor for these customers is that they have remote offices connected via MPLS networks. Naturally, the first thing we looked at was the query performance in SQL Profiler.  All of the queries were executing within expected timeframes, most of them were so fast that the duration in SQL Profiler was zero.  After getting nowhere with SQL Profiler, the situation was escalated to me.  I decided to take a peek with Process Monitor.  Procmon revealed some “gaps” in the TCP/IP traffic.  There were notable delays between send and receive pairs.  The send and receive pairs themselves were quite snappy, but quite often there was a notable delay between a receive and the next send.  You might expect some delay because, presumably, the application is doing some thinking in-between the pairs.  But, comparing the procmon data at the remote locations with the procmon data for workstations on the local network showed that the remote workstations were significantly delayed.  Procmon also showed a high number of disconnects. Wireshark traces showed that connections to the database were taking between 75ms and 150ms.  Not only that, but connections to a file share containing images were taking 2 seconds!  So, I asked about a trust.  Sure enough there was a trust between two domains and the file share was on the second domain.  Joining a remote workstation to the domain hosting the share containing images alleviated the time delay in accessing the file share.  Removing the trust had no affect on the connections to the database. Microsoft Network Monitor includes filters that parse TDS packets.  TDS is the protocol that SQL Server uses to communicate.  There is a certificate exchange and some SSL that occurs during authentication.  All of this was evident in the network traffic.  After staring at the network traffic for a while, and examining packets, I decided to call it a night.  On the way home that night, something about the traffic kept nagging at me.  Then it dawned on me…at the beginning of the dance of packets between the client and the server all was well.  Connection pooling was working and I could see multiple queries getting executed on the same connection and ethereal port.  After a particular query, connecting to two different servers, I noticed that ADODB and SQLOLEDB started making repeated connections to the database on different ethereal ports.  SQL Server would execute a single query and respond on a port, then open a new port and execute the next query.  Connection pooling appeared to be broken. The next morning I wrote a test to confirm my hypothesis.  Turns out that the sequence causing the connection nastiness goes something like this: Make a connection to the database. Open a result set that returns enough records to require multiple roundtrips to the server. For each result, query for some other data in the database (this will open a new implicit connection.) Close the inner result set and repeat for every item in the original result set. Close the original connection. Provided that the first result set returns enough data to require multiple roundtrips to the server, ADODB and SQLOLEDB will start making new connections to the database for each query executed in the loop.  Originally, I thought this might be due to Microsoft’s denial of service (ddos) attack protection.  After turning those features off to no avail, I eventually thought to switch my queries to client-side cursors instead of server-side cursors.  Server-side cursors are the default, by the way.  Voila!  After switching to client-side cursors, the disconnects were gone and the above sequence yielded two connections as expected. While the real problem is the amount of time it takes to make connections over these MPLS networks (100ms on average), switching to client-side cursors made the problem go away.  Believe it or not, this is actually documented by Microsoft, and rather difficult to find.  (At least it was while we were trying to troubleshoot the problem!)  So, if you’re noticing performance issues on slower networks, or networks with slower switching, take a look at the traffic in a tool like Microsoft Network Monitor.  If you notice a high number of disconnects, and you’re using fire-hose or server-side cursors, then try switching to client-side cursors and you may see the problem go away. Most likely, Microsoft believes this to be appropriate behavior, because ADODB can’t guarantee that all of the data has been retrieved when you execute the inner queries.  I’m not convinced, though, because the problem remains even after replacing all of the implicit connections with explicit connections and closing those connections in-between each of the inner queries.  In that case, there doesn’t seem to be a reason why ADODB can’t use a single connection from the connection pool to make the additional queries, bringing the total number of connections to two.  Instead ADO appears to make an assumption about the state of the connection. I’ve reported the behavior to Microsoft and am awaiting to hear from the appropriate team, so that I can demonstrate the problem.  Maybe they can explain to us why this is appropriate behavior.  :)

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  • Window management shortcuts?

    - by pwnguin
    I've got a single massive monitor at home, and I've decided to mimic the Windows 7 window tiling shortcuts. I found a few guides online using wmctrl, and it's going well, save one thing: maximized windows don't respond to it. gconftool-2 --type string --set /apps/metacity/keybinding_commands/command_1 "wmctrl -r :ACTIVE: -e 0, 0,0, `xwininfo -root | grep Width | awk '{ print ($2/2)}'`, `xwininfo -root | grep Height | awk '{ print $2 }'`" (I've added line returns to make an otherwise massive one-liner readable.) I've bound this to a hotkey and it works, unless the window is maximized. Any ideas on how to fix this up?

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  • Oracle Business Intelligence integration with Oracle Open Office

    - by Harald Behnke
    A highlight of the latest Oracle Office product launches are the first Oracle application connectors introduced with Oracle Open Office 3.3. The Oracle Open Office Connector for Oracle Business Intelligence perfectly demonstrates the advantages of enterprise and office productivity software engineered to work together. The connector enables you to access and run Oracle Business Intelligence Enterprise Edition requests directly within Oracle Open Office. The refreshable requests leverage not only native Open Office functionality but also the scalability and performance of the Oracle Oracle Business Intelligence server (R10.x). The requests reference a single source of information as defined in the Oracle Business Intelligence server data thus ensuring consistent information across the enterprise. See how it works in the demo video: Beyond the dramatic license cost savings for Oracle Business Intelligence customers using Oracle Open Office, the joint engineering efforts result in usability and efficiency benefits not available with Microsoft Office: Import styles and conditional formats defined in Business Intelligence answersApply customized styles, direct or conditional formats to Oracle Business Intelligence data - all changes are preserved during refreshChange chart properties for Oracle Open Office charts - all changes are preserved during refresh Read more about the Oracle Open Office enterprise features.

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  • Exadata Storage Server software upgrade is a new era in Patching

    - by Luis Moreno Campos
    Since it was first released, Exadata Storage Server software has been releasing patch releases like every software on the planet. Storage administrators would have to do this, but by some weird tradition, no matter what level of technology, if it says "Oracle" in it, IT Managers will immediately associate this with a task for the DBA. Not the case, but if it falls onto a DBA lap, fear no evil.The last patch released for Exadata Cells, is a true master piece in patching technology. This sentence is not mine, it's from both the customer and the partner that witnessed how 3 Exadata Cells where patch in less than 4 hours, after 12 months of without a single upgrade.The patch manager that takes care of everything will patch not only the software but also the firmware and the operating system. And you know it will all work out because back in the lab everything was already tested.All you have to do is stare at the 3 Sun ILOM Windows from the 3 cells and watch as they boot and reboot, patch and fix to the latest versions all layers of the storage machines. It's a new era in Patching technology!LMC

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  • ATI radeon graphics card and screen freeze problem

    - by Thomas
    recently i upgrade my machine with new hardware component. my mother board is Gigabyte, processor Intel i3 3.6 ghz, ram 4 gb, graphics card ATI radeon 4350 1 GB. my OS installed is windows XP. when i am trying to play call of duty black ops then screen gets freeze and when i try to play other game like medal of honour then suddenly game closed suddenly after 15 or 20 minutes. i am not being able to find out the problem. whether i have problem in RAM or Graphics card. i asked few hardware person and one of them told me that i should installed windows 7 rather than windows xp. is it true. please help me to understand the problem and also tell me what should i do to fix this problem. please discuss in detail. thanks in advance. Update: yes i already install lates driver for ATI radeon 4350 but still the problem persist. do i need to install windows 7 instead of win xp because my processor is intel i3.

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  • Big Data – What is Big Data – 3 Vs of Big Data – Volume, Velocity and Variety – Day 2 of 21

    - by Pinal Dave
    Data is forever. Think about it – it is indeed true. Are you using any application as it is which was built 10 years ago? Are you using any piece of hardware which was built 10 years ago? The answer is most certainly No. However, if I ask you – are you using any data which were captured 50 years ago, the answer is most certainly Yes. For example, look at the history of our nation. I am from India and we have documented history which goes back as over 1000s of year. Well, just look at our birthday data – atleast we are using it till today. Data never gets old and it is going to stay there forever.  Application which interprets and analysis data got changed but the data remained in its purest format in most cases. As organizations have grown the data associated with them also grew exponentially and today there are lots of complexity to their data. Most of the big organizations have data in multiple applications and in different formats. The data is also spread out so much that it is hard to categorize with a single algorithm or logic. The mobile revolution which we are experimenting right now has completely changed how we capture the data and build intelligent systems.  Big organizations are indeed facing challenges to keep all the data on a platform which give them a  single consistent view of their data. This unique challenge to make sense of all the data coming in from different sources and deriving the useful actionable information out of is the revolution Big Data world is facing. Defining Big Data The 3Vs that define Big Data are Variety, Velocity and Volume. Volume We currently see the exponential growth in the data storage as the data is now more than text data. We can find data in the format of videos, musics and large images on our social media channels. It is very common to have Terabytes and Petabytes of the storage system for enterprises. As the database grows the applications and architecture built to support the data needs to be reevaluated quite often. Sometimes the same data is re-evaluated with multiple angles and even though the original data is the same the new found intelligence creates explosion of the data. The big volume indeed represents Big Data. Velocity The data growth and social media explosion have changed how we look at the data. There was a time when we used to believe that data of yesterday is recent. The matter of the fact newspapers is still following that logic. However, news channels and radios have changed how fast we receive the news. Today, people reply on social media to update them with the latest happening. On social media sometimes a few seconds old messages (a tweet, status updates etc.) is not something interests users. They often discard old messages and pay attention to recent updates. The data movement is now almost real time and the update window has reduced to fractions of the seconds. This high velocity data represent Big Data. Variety Data can be stored in multiple format. For example database, excel, csv, access or for the matter of the fact, it can be stored in a simple text file. Sometimes the data is not even in the traditional format as we assume, it may be in the form of video, SMS, pdf or something we might have not thought about it. It is the need of the organization to arrange it and make it meaningful. It will be easy to do so if we have data in the same format, however it is not the case most of the time. The real world have data in many different formats and that is the challenge we need to overcome with the Big Data. This variety of the data represent  represent Big Data. Big Data in Simple Words Big Data is not just about lots of data, it is actually a concept providing an opportunity to find new insight into your existing data as well guidelines to capture and analysis your future data. It makes any business more agile and robust so it can adapt and overcome business challenges. Tomorrow In tomorrow’s blog post we will try to answer discuss Evolution of Big Data. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: Big Data, PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL

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  • The Beginner’s Guide To Tabbed Browsing

    - by Chris Hoffman
    Tabs allow you to open multiple web pages in a single browser window without cluttering your desktop. Mastering tabbed browsing can speed up your browsing experience and make multiple web pages easier to manage. Tabbed browsing was once the domain of geeks using alternative browsers, but every popular browser now supports tabbed browsing – even mobile browsers on smartphones and tablets. This article is intended for beginners. If you know someone that doesn’t fully understand tabbed browsing and how awesome it is, feel free to send it to them! How Hackers Can Disguise Malicious Programs With Fake File Extensions Can Dust Actually Damage My Computer? What To Do If You Get a Virus on Your Computer

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  • Help building maya render node spec

    - by Ak
    Hi there, I'm looking to build 4x Maya render slaves/nodes for a friend of mine when his project gets green lit. The project involves MentalRay and lots of glass. I'm unsure if the new i7's 9xx or 8xx with hyper threading will do any better than a core 2 quad of the same (or close enough) speed. Does hyper threading make a difference to Maya or is it more performance per core based? I'm sure he's prefer I'd build another render node than pay for a bleeding edge CPU that only adds fractionly more GHz. -- The rest of the spec so far: 4Gb - 8Gb ram 64 bit OS: Probably Windows 7 (I know Linux is free, but want to build something my friend can support himself as easily as he supports his own workstation) 1TB HDD to hold textures, Maya files and renders which will be copied to central storage later Mobo with on-board video, gigabit NIC 500 - 650 watt PSU Desktop case something like a: Cooler Master ATCS 840 The machines will sold afterwards if necessary. -- If anyone has had experience in Maya and has done any tests with the new CPUs vs. the older ones I'd really appreciate your input.

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  • Is it possible to shrink the size of an HP Smart Array logical drive?

    - by ewwhite
    I know extension is quite possible using the hpacucli utility, but is there an easy way to reduce the size of an existing logical drive (not array)? The controller is a P410i in a ProLiant DL360 G6 server. I'd like to reduce logicaldrive 1 from 72GB to 40GB. => ctrl all show config detail Smart Array P410i in Slot 0 (Embedded) Bus Interface: PCI Slot: 0 Serial Number: 5001438006FD9A50 Cache Serial Number: PAAVP9VYFB8Y RAID 6 (ADG) Status: Disabled Controller Status: OK Chassis Slot: Hardware Revision: Rev C Firmware Version: 3.66 Rebuild Priority: Medium Expand Priority: Medium Surface Scan Delay: 3 secs Surface Scan Mode: Idle Queue Depth: Automatic Monitor and Performance Delay: 60 min Elevator Sort: Enabled Degraded Performance Optimization: Disabled Inconsistency Repair Policy: Disabled Wait for Cache Room: Disabled Surface Analysis Inconsistency Notification: Disabled Post Prompt Timeout: 15 secs Cache Board Present: True Cache Status: OK Accelerator Ratio: 25% Read / 75% Write Drive Write Cache: Enabled Total Cache Size: 512 MB No-Battery Write Cache: Disabled Cache Backup Power Source: Batteries Battery/Capacitor Count: 1 Battery/Capacitor Status: OK SATA NCQ Supported: True Array: A Interface Type: SAS Unused Space: 412476 MB Status: OK Logical Drive: 1 Size: 72.0 GB Fault Tolerance: RAID 1+0 Heads: 255 Sectors Per Track: 32 Cylinders: 18504 Strip Size: 256 KB Status: OK Array Accelerator: Enabled Unique Identifier: 600508B1001C132E4BBDFAA6DAD13DA3 Disk Name: /dev/cciss/c0d0 Mount Points: /boot 196 MB, / 12.0 GB, /usr 8.0 GB, /var 4.0 GB, /tmp 2.0 GB OS Status: LOCKED Logical Drive Label: AE438D6A5001438006FD9A50BE0A Mirror Group 0: physicaldrive 1I:1:1 (port 1I:box 1:bay 1, SAS, 146 GB, OK) physicaldrive 1I:1:2 (port 1I:box 1:bay 2, SAS, 146 GB, OK) Mirror Group 1: physicaldrive 1I:1:3 (port 1I:box 1:bay 3, SAS, 146 GB, OK) physicaldrive 1I:1:4 (port 1I:box 1:bay 4, SAS, 146 GB, OK) SEP (Vendor ID PMCSIERA, Model SRC 8x6G) 250 Device Number: 250 Firmware Version: RevC WWID: 5001438006FD9A5F Vendor ID: PMCSIERA Model: SRC 8x6G

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  • webserver horrible slow, sometimes incredible fast

    - by dhanke
    i am running a small community ( 6000+ Members ) on a non-virtual 64-bit ubuntu 11.04 system. I am not a Linux-pro, not even advanced, i just tried to setup a webserver, which does nothing special actually. Delivering some dynamic PHP and RoR websites is its task. So it might be that my configuration files do look horrible bad. Also, i might use the wrong vocabulary, so in doubt, please ask. Having a current all-time record of 520 registered users (board-accounts, no system-users) online at same time, average server-load is about 2.0 - 5.0. Meantime (~250 users) average server load value is at about 0.4 - 0.8, sometimes, on some expensive searches a bit higher. everything fine. From time to time however, the load increases up to 120 (120.0, not 12.0 ;) ). In this time, its hard to even connect via SSH, but when i reach the server, and use top/htop/iotop to see whats happening, i cannot identify any process causing high CPU load. iotop tells me about a current reading/writing speed of about approx. 70kb/s, which is quite equal to power-off i think. Memory-Usage is max. at ~ 12GB of 16GB, so swap remains empty. now the odd (at least for me:) waiting some minutes ( since i always get a bit into a panic when this happens, it feels like 5 minutes, but i suppose its more like 20-30 minutes) and the server is back to normal. everything continues as normal. another odd fact: when i run hdparm -tT /dev/sda, i get answer like: /dev/sda: Timing cached reads: 7180 MB in 2.00 seconds = 3591.13 MB/sec Timing buffered disk reads: 348 MB in 3.02 seconds = 115.41 MB/sec when i run the same command while the server is "frozen", the answer is like /dev/sda: <- takes about 5 minutes until this line appears Timing cached reads: 7180 MB in 2.00 seconds = 3591.13 MB/sec <- 5 more minutes Timing buffered disk reads: 348 MB in 3.02 seconds = 115.41 MB/sec <- another 5 minutes so the values are the same, but the quoted time is completely wrong. using time command as prefix also tells me that ~ 15 minutes were used. I searched in dmesg, /var/log/[messages|syslog] - nothing found. /var/log/errors however tells me that: Jul 4 20:28:30 localhost kernel: [19080.671415] INFO: task php5-fpm:27728 blocked for more than 120 seconds. Jul 4 20:28:30 localhost kernel: [19080.671419] "echo 0 /proc/sys/kernel/hung_task_timeout_secs" disables this message. multiple times. now that message does tell me that php5-fpm task was blocked or did block ? - but not if that is the cause or just one of the results of that "freeze". Anyone? to cut the long story short, i dont know where even to start analyzing. So if you can give me any advice by looking at following specs and configs, or ask me to provide more information, i`d be glad. Specs: 6 Core AMD Phenom(tm) II X6 1055T Processor * 16 Gigabyte Ram 2x 1.5 TB Seagate ST1500DL003-9VT16L via SATA 3 via SoftwareRaid (i suppose) Services: (due to service --status-all, those with [ + ]) nginx Webserver 1.0.14 mySQL 5.1.63 Server Ruby on Rails 2.3.11 ( passenger-nginx-module ) php5-fpm 5.3.6-13ubuntu3.7 SSH ido2db Further services: default crontab + nightly backup. syslog-ng Website consists of 2 subdomains, forum. and www. where forum is a phpBB3.x PHP-Board, and www a Ruby on Rails 2.3.11 application (portal). Mini-Note: sometimes i notice that the forum is pretty slow, in contrast to the always-fast (except for this "freeze") portal. Both share the same Database, but the portal is using it read-only. The Webserver is nginx, using phusion passenger module to communicate with the ruby-application. Also, for the forum it communicates with php5-fpm via socket: relevant nginx configuration parts ( with comments/questions starting by ; ) ; in case of freeze due to too high Filesystem activity, maybe adding a limit? #worker_rlimit_nofile 50000; user www-data; ; 6 cores, so i read 6 fits. maybe already wrong? worker_processes 6; pid /var/run/nginx.pid; events { worker_connections 1024; } http { passenger_root /var/lib/gems/1.8/gems/passenger-3.0.11; passenger_ruby /usr/bin/ruby1.8; ; the forum once featured a chat, which was working w/o websockets. ; so it was a hell of pull requests (deactivated now, freeze still happening) keepalive_timeout 65; keepalive_requests 50; gzip on; server { listen 80; server_name www.domain.tld; root /var/www/domain/rails/public; passenger_enabled on; } server { listen 80; server_name forum.domain.tld; location / { root /var/www/domain/forum; index index.php; } ; satic stuff to be handled by nginx location ~* ^/style/.+.(jpg|jpeg|gif|css|png|js|ico|xml)$ { access_log off; expires 30d; root /var/www/domain/forum/; } ; now the php magic, note the "backend"-fcgi_pass location ~ .php$ { fastcgi_split_path_info ^(.+\.php)(.*)$; fastcgi_pass backend; fastcgi_index index.php; fastcgi_param SCRIPT_FILENAME /var/www/domain/forum$fastcgi_script_name; include fastcgi_params; fastcgi_param QUERY_STRING $query_string; fastcgi_param REQUEST_METHOD $request_method; fastcgi_param CONTENT_TYPE $content_type; fastcgi_param CONTENT_LENGTH $content_length; fastcgi_intercept_errors on; fastcgi_ignore_client_abort off; fastcgi_connect_timeout 60; fastcgi_send_timeout 180; fastcgi_read_timeout 180; fastcgi_buffer_size 128k; fastcgi_buffers 256 16k; fastcgi_busy_buffers_size 256k; fastcgi_temp_file_write_size 256k; fastcgi_max_temp_file_size 0; } location ~ /\.ht { deny all; } } ;the php5-fpm socket. i read that /dev/shm/ whould be the fastes place for this. bad idea in general? upstream backend { server unix:/dev/shm/phpfpm; } ... } php5-fpm settings (i changed this values due to php5-fpm error log messages higher and higher.. (freeze-problem was there before as well)* listen = /dev/shm/phpfpm user = www-data group = www-data pm = dynamic ; holy, 4000! well, shinking this value to earth-level gave me ; 100s of 502 bad gateway commands. this values were quite stable. ; since there are only max 520 users online i dont get it, why i would need ; as many children as configured here. due to keep-alive maybe? ; asking questions is easier for me since restarting server will make ; my community-members angry ;) pm.max_children = 4000 pm.start_servers = 100 pm.min_spare_servers = 50 pm.max_spare_servers = 150 pm.max_requests = 10 pm.status_path = /status ping.path = /ping ping.response = pong slowlog = log/$pool.log.slow ;should i use rlimit? ;rlimit_files = 1024 chdir = / mysql/my.cnf [client] port = 3306 socket = /var/run/mysqld/mysqld.sock [mysqld_safe] socket = /var/run/mysqld/mysqld.sock nice = 0 [mysqld] user = mysql socket = /var/run/mysqld/mysqld.sock port = 3306 basedir = /usr datadir = /var/lib/mysql tmpdir = /tmp skip-external-locking bind-address = 127.0.0.1 key_buffer = 16M max_allowed_packet = 16M thread_stack = 192K thread_cache_size = 8 myisam-recover = BACKUP ; high number, but less gives some phpBB errors. max_connections = 450 table_cache = 512 ; i read twice the cpu cores, bad? thread_concurrency = 12 join_buffer_size = 2084K concurrent_insert = 3 query_cache_limit = 64M query_cache_size = 512M query_cache_type = 1 log_error = /var/log/mysql/error.log log_slow_queries = /var/log/mysql/mysql-slow.log long_query_time = 2 expire_logs_days = 10 max_binlog_size = 100M low_priority_updates=1 [mysqldump] quick quote-names max_allowed_packet = 16M [isamchk] key_buffer = 16M !includedir /etc/mysql/conf.d/ I used smartctl already, hdds seem to be fine. /proc/mdstatus quotes: Personalities : [raid1] [linear] [multipath] [raid0] [raid6] [raid5] [raid4] [raid10] md3 : active raid1 sda3[1] 1459264192 blocks [2/1] [_U] md1 : active raid1 sda1[0] 3911680 blocks [2/1] [U_] unused devices: ulimit -a core file size (blocks, -c) 0 data seg size (kbytes, -d) unlimited scheduling priority (-e) 0 file size (blocks, -f) unlimited pending signals (-i) 127727 max locked memory (kbytes, -l) 64 max memory size (kbytes, -m) unlimited open files (-n) 1024 pipe size (512 bytes, -p) 8 POSIX message queues (bytes, -q) 819200 real-time priority (-r) 0 stack size (kbytes, -s) 8192 cpu time (seconds, -t) unlimited max user processes (-u) 127727 virtual memory (kbytes, -v) unlimited file locks (-x) unlimited I quote some questions in my configuration files, these are not (intentional) directly problem-related, but would be nice for me to know wether they are indeed questionable or done right. One additional Fact: my MYSQL-database is at 12GB size. i dont know if that does matter, but mytop sometimes shows me 4-5 seconds long insert queries, some are 20-30 seconds long. Its just a feeling that i am unable to prove (because i dont know how), but when i disable the database, the freeze seems not to happen. Example: i created a dummy rails application to see the development log. the app made some sql-queries, reads and inserts. the log quite often was like: DbTest Load (0.3ms) SELECT * FROM `db_test` WHERE (`db_test`.`id` = 31722) LIMIT 1 SQL (0.1ms) BEGIN DbTest Update (0.3ms) UPDATE `db_test` SET `updated_at` = '2012-07-04 23:32:34' WHERE `id` = 31722 - now the log stands still for 5-60 seconds. SQL (49.1ms) COMMIT - SQL-Update time in the log does not include freeze time Rendering test/index Completed in 96ms (View: 16, DB: 59) | 200 OK [http://localhost:9000/test] Bad part is: this mini-freeze here only happens from time to time as well. note: meanwhile i cannot even upload files via scp. I currently feel like running form bad to worse and back by googling for my server-problem due to immense lack of knowledge regarding server configurations. It still makes me wonder, why those problems even appear, since 250 users a time is not such a high amount, right? So my questions: whats wrong and how to fix? ;) or: what information can i provide to make the situation more clear? can you point at some critical bad configuration-line which i should consider to catch up in the documentation? are there any tools i can run to see some possible bottlenecks? any further advice? (next to: "pay someone who knows what he does" - its a private project, server costs enough already. :)) Thanks for your time and help. Best Regards, Daniel P.S.: i renamed the configfiles to domain.tld since i dont want to have any % more load to the server until its fixed. might be a exaggeratedly thought.. P.P.S: if i asked a complete duplicate question, sorry. my search results seemed to be quite specific in their own way.

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  • How do multiple displays work on a AMD 785G / ATI HD 4200 motherboard?

    - by aireq
    I just ordered a ASUS M4A785TD-V EVO which has the AMD 785G chipset and HD4200 integrated graphic. The board has VGA, DVI, and HDMI outputs. I'm wondering how many outputs I can run at once, and from what connectors? My guess is that I can only use the VGA, and either the DVI or the HDMI in a dual setup. But not the HDMI and the DVI at the same time. Is this correct? If I have devices plugged into both the HDMI and the DVI ports is there a way to choose between which port I want to use? I have a dual 19" monitor setup, as well as a LCD TV. I'd like to run the VGA and the DVI into my two monitors, and then the HDMI to my TV. Then when I want to watch something on the TV I'd like to be able to switch over from the DVI to the HDMI. Is this possible with out crawling under my desk and unplugging/plugging things in? Update I found the following in the manual off ASUS's website, which confirms my original suspicion that HDMI and DVI can't be used at the same time. But I'd still like to know if it's possible through software to switch between using the HDMI and DVI.

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  • NVidia ION and /dev/mapper/nvidia_... issues.

    - by Ritsaert Hornstra
    I have an NVidia ION board with 4 SATA ports and want to use that to run a Linux Server (CentOS 5.4). I first hooed up 3 HDs (that will be a RAID5 array) and a forth small boot HD. I first started to use the onboard RAID capability but that does not work correctly under Linux: the raid capacity is not a real RAID but uses lvm to define some arays. After setting the BIOS back to normal SATA mode and whiping the HDs, the first boot harddisk (/dev/sda) is seen as /dev/sda BEFORE mounting and after mounting as /dev/mapper/nvidia_. CentOS is unable to install on it (and grub is not installable on it either). So somehow the harddisk is still seen as if it belongs to some lvm volume. I tried to clean out the HD by issuing a few dd if=/dev/zero of=/dev/sda commands to wipe the starting cylinders and final cylinders but to no avail. Did anyone see this problem and did anyone find a solution? UPDATE When I create only a single ext3 partition on the first HD (/dev/mapper/nvidia_...) no LVM partitions are seen and I can boot from /dev/mapper/nvidia_.... Now the next step is to see how I can get rid of this folly.

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  • Dynamic Data Connections

    - by Tim Dexter
    I have had a long running email thread running between Dan and David over at Valspar and myself. They have built some impressive connectivity between their in house apps and BIP using web services. The crux of their problem has been that they have multiple databases that need the same report executed against them. Not such an unusual request as I have spoken to two customers in the last month with the same situation. Of course, you could create a report against each data connection and just run or call the appropriate report. Not too bad if you have two or three data connections but more than that and it becomes a maintenance nightmare having to update queries or layouts. Ideally you want to have just a single report definition on the BIP server and to dynamically set the connection to be used at runtime based on the user or system that the user is in. A quick bit of digging and help from Shinji on the development team and I had an answer. Rather embarassingly, the solution has been around since the Oct 2010 rollup patch last year. Still, I grabbed the latest Jan 2011 patch - check out Note 797057.1 for the latest available patches. Once installed, I used the best web service testing tool I have yet to come across - SoapUI. Just point it at the WSDL and you can check out the available services and their parameters and then test them too. The XML packet has a new dynamic data source entry. You can set you own custom JDBC connection or just specify an existing data source name thats defined on the server. <pub:runReport> <pub:reportRequest> <pub:attributeFormat>xml</pub:attributeFormat> <pub:attributeTemplate>0</pub:attributeTemplate> <pub:byPassCache>true</pub:byPassCache> <pub:dynamicDataSource> <pub:JDBCDataSource> <pub:JDBCDriverClass></pub:JDBCDriverClass> <pub:JDBCDriverType></pub:JDBCDriverType> <pub:JDBCPassword></pub:JDBCPassword> <pub:JDBCURL></pub:JDBCURL> <pub:JDBCUserName></pub:JDBCUserName> <pub:dataSourceName>Conn1</pub:dataSourceName> </pub:JDBCDataSource> </pub:dynamicDataSource> <pub:reportAbsolutePath>/Test/Employee Report/Employee Report.xdo</pub:reportAbsolutePath> </pub:reportRequest> <pub:userID>Administrator</pub:userID> <pub:password>Administrator</pub:password> </pub:runReport> So I have Conn1 and Conn2 defined that are connections to different databases. I can just flip the name, make the WS call and get the appropriate dataset in my report. Just as an example, here's my web service call java code. Just a case of bringing in the BIP java libs to my java project. publicReportServiceService = new PublicReportServiceService(); PublicReportService publicReportService = publicReportServiceService.getPublicReportService_v11(); String userID = "Administrator"; String password = "Administrator"; ReportRequest rr = new ReportRequest(); rr.setAttributeFormat("xml"); rr.setAttributeTemplate("1"); rr.setByPassCache(true); rr.setReportAbsolutePath("/Test/Employee Report/Employee Report.xdo"); rr.setReportOutputPath("c:\\temp\\output.xml"); BIPDataSource bipds = new BIPDataSource(); JDBCDataSource jds = new JDBCDataSource(); jds.setDataSourceName("Conn1"); bipds.setJDBCDataSource(jds); rr.setDynamicDataSource(bipds); try { publicReportService.runReport(rr, userID, password); } catch (InvalidParametersException e) { e.printStackTrace(); } catch (AccessDeniedException e) { e.printStackTrace(); } catch (OperationFailedException e) { e.printStackTrace(); } } Note, Im no java whiz kid or whizzy old bloke, at least not unless Ive had a coffee. JDeveloper has a nice feature where you point it at the WSDL and it creates everything to support your calling code for you. Couple of things to remember: 1. When you call the service, remember to set the bypass the cache option. Forget it and much scratching of your head and taking my name in vain will ensue. 2. My demo actually hit the same database but used two users, one accessed the base tables another views with the same name. For far too long I thought the connection swapping was not working. I was getting the same results for both users until I realized I was specifying the schema name for the table/view in my query e.g. select * from EMP.EMPLOYEES. So remember to have a generic query that will depend entirely on the connection. Its a neat feature if you want to be able to switch connections and only define a single report and call it remotely. Now if you want the connection to be set dynamically based on the user and the report run via the user interface, thats going to be more tricky ... need to think about that one!

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  • UKOUG Application Server & Middleware SIG Meeting

    - by JuergenKress
    Date: Wednesday 10th Oct 2012 Time: 09:00 - 16:00 Location: Reading Venue: Oracle, Thames Valley Park, Reading Agenda: 09:00 Registration and Coffee 10:00 Welcome Application Server & Middleware Committee 10:10 Oracle Support Updates Nick Pounder, Oracle Customer Services 10:30 OpenWorld 2012 - News Round-up for Middleware Admins Simon Haslam, Veriton Limited 11:00 Coffee break 11:20 Oracle Single-Sign on to Oracle Access Manager Migration Rob Otto, Oracle Consulting Services UK 12:05 Supporting Fusion Middleware through First Failure Capture (theory) Greg Cook, Oracle 12:50 Lunch and Network 13:35 Deputy Chair Elections UKOUG 13:45 Supporting Fusion Middleware through First Failure Capture (demos) Greg Cook, Oracle 14:15 Networking session including tea/coffee 14:45 Real Life WebLogic Performance Tuning: Tales and Techniques from the Field Steve Millidge, C2B2 Consulting Limited 15:30 WLST: WebLogic's Swiss Army Knife Simon Haslam, Veriton Limited 15:45 AOB and Close For details please visit the registration page. WebLogic Partner Community For regular information become a member in the WebLogic Partner Community please visit: http://www.oracle.com/partners/goto/wls-emea ( OPN account required). If you need support with your account please contact the Oracle Partner Business Center. BlogTwitterLinkedInMixForumWiki Technorati Tags: UK user group,Simon Haslam,WebLogic Community,Oracle,OPN,Jürgen Kress

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  • The curious case(s) of the Microsoft product naming department

    - by AaronBertrand
    A long time ago, in a galaxy far, far away... Okay, it was here on earth, a little over 5 years ago. With SQL Server 2005, Microsoft introduced a very useful feature called the DAC. DAC stands for "dedicated administrator connection"... you can read about it here , but essentially, it allows you a single connection into the server with priority resource allocation - so you can actually get in and kill a rogue process that is otherwise taking over the server. On its own this was a fine acronym choice,...(read more)

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  • Writing C# Code Using SOLID Principles

    - by bipinjoshi
    Most of the modern programming languages including C# support objected oriented programming. Features such as encapsulation, inheritance, overloading and polymorphism are code level features. Using these features is just one part of the story. Equally important is to apply some object oriented design principles while writing your C# code. SOLID principles is a set of five such principles--namely Single Responsibility Principle, Open/Closed Principle, Liskov Substitution Principle, Interface Segregation Principle and Dependency Inversion Principle. Applying these time proven principles make your code structured, neat and easy to maintain. This article discusses SOLID principles and also illustrates how they can be applied to your C# code.http://www.binaryintellect.net/articles/7f857089-68f5-4d76-a3b7-57b898b6f4a8.aspx 

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  • SQL In The City Charlotte - Fundamentals of Database Design

    - by drsql
    Next Monday, October 14, at Red-Gate's SQL In The City conference in Charlotte, NC (one day before PASS), I will be presenting my Fundamentals of Database Design session. It is my big-time chestnut session, the one that I do the most and have the most fun with. This will be the "single" version of the session, weighing in at just under an hour, and it is a lot of material to go over (even with no code samples to go awry to take up time.)  In this hour long session (presented in widescreen...(read more)

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  • Class Loading Deadlocks

    - by tomas.nilsson
    Mattis follows up on his previous post with one more expose on Class Loading Deadlocks As I wrote in a previous post, the class loading mechanism in Java is very powerful. There are many advanced techniques you can use, and when used wrongly you can get into all sorts of trouble. But one of the sneakiest deadlocks you can run into when it comes to class loading doesn't require any home made class loaders or anything. All you need is classes depending on each other, and some bad luck. First of all, here are some basic facts about class loading: 1) If a thread needs to use a class that is not yet loaded, it will try to load that class 2) If another thread is already loading the class, the first thread will wait for the other thread to finish the loading 3) During the loading of a class, one thing that happens is that the <clinit method of a class is being run 4) The <clinit method initializes all static fields, and runs any static blocks in the class. Take the following class for example: class Foo { static Bar bar = new Bar(); static { System.out.println("Loading Foo"); } } The first time a thread needs to use the Foo class, the class will be initialized. The <clinit method will run, creating a new Bar object and printing "Loading Foo" But what happens if the Bar object has never been used before either? Well, then we will need to load that class as well, calling the Bar <clinit method as we go. Can you start to see the potential problem here? A hint is in fact #2 above. What if another thread is currently loading class Bar? The thread loading class Foo will have to wait for that thread to finish loading. But what happens if the <clinit method of class Bar tries to initialize a Foo object? That thread will have to wait for the first thread, and there we have the deadlock. Thread one is waiting for thread two to initialize class Bar, thread two is waiting for thread one to initialize class Foo. All that is needed for a class loading deadlock is static cross dependencies between two classes (and a multi threaded environment): class Foo { static Bar b = new Bar(); } class Bar { static Foo f = new Foo(); } If two threads cause these classes to be loaded at exactly the same time, we will have a deadlock. So, how do you avoid this? Well, one way is of course to not have these circular (static) dependencies. On the other hand, it can be very hard to detect these, and sometimes your design may depend on it. What you can do in that case is to make sure that the classes are first loaded single threadedly, for example during an initialization phase of your application. The following program shows this kind of deadlock. To help bad luck on the way, I added a one second sleep in the static block of the classes to trigger the unlucky timing. Notice that if you uncomment the "//Foo f = new Foo();" line in the main method, the class will be loaded single threadedly, and the program will terminate as it should. public class ClassLoadingDeadlock { // Start two threads. The first will instansiate a Foo object, // the second one will instansiate a Bar object. public static void main(String[] arg) { // Uncomment next line to stop the deadlock // Foo f = new Foo(); new Thread(new FooUser()).start(); new Thread(new BarUser()).start(); } } class FooUser implements Runnable { public void run() { System.out.println("FooUser causing class Foo to be loaded"); Foo f = new Foo(); System.out.println("FooUser done"); } } class BarUser implements Runnable { public void run() { System.out.println("BarUser causing class Bar to be loaded"); Bar b = new Bar(); System.out.println("BarUser done"); } } class Foo { static { // We are deadlock prone even without this sleep... // The sleep just makes us more deterministic try { Thread.sleep(1000); } catch(InterruptedException e) {} } static Bar b = new Bar(); } class Bar { static { try { Thread.sleep(1000); } catch(InterruptedException e) {} } static Foo f = new Foo(); }

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  • Bundled Software Installers

    - by Volomike
    I have two unrelated Windows programs that come with their own setup.exe files. Using a third-party tool, how do I bundle the two in a single installer? The setup wizard functionality would work like this: They run my setup.exe. It's primary goal is to install Windows program A. On page 2 of the installer, it has a checkbox to install Windows program B. When they click Next on page 2, my installer window vanishes and Windows program A's installer runs. When that installer finishes, my installer detects this. If Windows program B was selected to also be installed, its installer runs next, and again with my installer window not shown. When step 4 is done, my installer detects one or both installs are finished and shows a Finish page from my installer. The user clicks that and my installer closes because it has concluded its purpose.

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  • Three Ways to Access the Windows 8 Boot Options Menu

    - by Lori Kaufman
    The boot options have been consolidated in Windows 8 into a single menu, called the “boot options menu,” providing access to repair tools and options for changing Windows startup behavior, such as enabling debugging, booting into safe mode, and launching into a recovery environment. The days of pressing a function key or Esc to interrupt the boot process and get into the BIOS configuration (in UEFI enabled systems) are gone. There are three ways of accessing the new boot options menu in Windows 8 and we’ll show you how. 7 Ways To Free Up Hard Disk Space On Windows HTG Explains: How System Restore Works in Windows HTG Explains: How Antivirus Software Works

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  • Oracle Announces New Oracle VM Template for MySQL Enterprise Edition

    - by Zeynep Koch
     Oracle announces new Oracle VM template for MySQL Enterprise Edition enabling more efficient and lower cost deployments of virtualized MySQL environments. Here are some of the details and benefits: The new Oracle VM Template for MySQL helps eliminate manual configuration efforts and risks by providing a pre-installed, pre-configured and certified software stack that includes Oracle VM Server for x86, Oracle Linux with the Unbreakable Enterprise Kernel and MySQL Enterprise Edition. By pre-integrating the world’s most popular open source database with Oracle Linux and Oracle Virtualization technologies, enterprise users and ISVs can quickly and easily deploy and manage a virtualized MySQL database server for Web and cloud-based applications. Backed by Oracle’s world-class support organization and the result of extensive integration and quality assurance testing, the Oracle VM Template for MySQL Enterprise Edition further demonstrates Oracle’s investment in MySQL and allows users to benefit from a single point of contact for 24/7 technical support for all pre-configured components. Read more in this white paper. 

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  • I cannot format my PC

    - by Jesus Buelna
    I have a Toshiba Satellite(1) l505 6gb RAM, 6.00GB hard disk.Initially I have problem with another satellite(2) I had (mother board problem). I took my Laptop to a technician and cost a lot of money (almost as much as buying new one). So, since I have HDD problems with the first one(1) I decided to use the hard disk of the other one(2). I formatted the HDD and erased the partitions it had into 1 partition (or no partition). The problem is that when I try to format with the SO CD, in the screen, where I have to decide in which partition I want to install the SO, the only one option I have says "unallocated partition and I receive this message "Windows cannot install the SO in this partition, run files do not existed or maybe corrupted" When I erased the disk with Parted Magic, Did I erased any files needed for running the installing disk? I don't know. Is it possible to fixed or reinstate the disk to install the OS? By the way, I checked the disk physical health with Parted Magic, and it is OK. One more thing when I erased the disc to 0, I used the safety option offered by the Parted Magic.Need help please.

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