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  • Get Started with .Net and Apache Cassandra

    - by Sazzad Hossain
    Just came across a easy and nice to read article explaining how to get started with noSQL database system. These no relational databases are getting increasingly popular to tackle the distribution and large data set problems.Cassandra's ColumnFamily data model offers the convenience of column indexes with the performance of log-structured updates, strong support for materialized views, and powerful built-in caching.The article is nicely written by Kellabyte  and shows step by step process how to get going with the programming in a .net platform.Read more here.

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  • How to activate subwoofer in Inspiron 17r?

    - by alfC
    I have a Dell Inspiron 17r, after a fresh install of 12.10, the subwoofer seems to be not utilized. No sound comes from it and in the Sound Control Panel the settings appear grayed out (see screenshot). How can I activate the subwoofer? I tried adding the line options snd-hda-intel model=dell in the file /etc/modprobe.d/alsa-base.conf and enable-lfe-remixing = yes default-sample-channels = 3 in the file /etc/pulse/daemon.conf, but still doesn't work.

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  • Oracle Linux Friday Spotlight - October 18, 2013

    - by Chris Kawalek
    Happy Friday! Echoing our popular series over on the Oracle Virtualization blog, we'll now be spotlighting something interesting about Oracle Linux for you every Friday. This week, we have a really cool video done by Intel that features Oracle's Phillip Goerl discussing the Oracle Linux development model and how it relates to Intel Xeon. Click below to jump to YouTube and play the video: See you next week! -Chris 

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  • SSIS Design Patterns Training in London 8-11 Sep!

    - by andyleonard
    A few seats remain for my course SQL Server Integration Services 2012 Design Patterns to be delivered in London 8-11 Sep 2014. Register today to learn more about: New features in SSIS 2012 and 2014 Advanced patterns for loading data warehouses Error handling The (new) Project Deployment Model Scripting in SSIS The (new) SSIS Catalog Designing custom SSIS tasks Executing, managing, monitoring, and administering SSIS in the enterprise Business Intelligence Markup Language (Biml) BimlScript ETL Instrumentation...(read more)

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  • ACORD LOMA 2010: Building Insurance Companies in the Clouds

    - by [email protected]
    Chuck Johnston, vice president of global strategy and alliances for Oracle Insurance, participated in a featured speaking session at ACORD LOMA 2010. He provides an update on his discussions with insurers at the show and after his presentation. Every year I always make a point of walking the show floor at the ACORD LOMA technology conference to visit with colleagues and competitors, and try to get a feel for which way the industry will move over the next 12 months. Insurers are looking for substance in cloud (computing), trying to mix business with pleasure (monetizing social networks), and expect differentiation through commodity (Software as a Service). The disconnect at this show is that most vendors are still struggling with creating a clear path from Facebook to customer intimacy, SaaS to core cost savings and clouds to ubiquitous presence. Vendors need to find new ways to help insurers find the real value in these potentially disruptive technologies by understanding the changes coming to the insurance business and how these new technologies impact the new insurance business. Oracle's approach to understanding the evolving insurance industry comes from a discussion with our customers in our Insurance CIO Council, where one of our customers suggested we buy an insurance company to really understand our customers. We have decided to do the next best thing and build our own model of an insurance company, Alamere Insurance, that uses the latest technologies to transform its own business. Alamere will never issue an actual policy, but it does give us a framework to consider the impacts of changes in the insurance landscape and how Oracle technology meets the challenge or needs to evolve to help our customers be successful. In preparing for my talk at the conference using Alamere as my organizing theme, I found myself reading actuarial memoranda on CSO table changes and articles on underwriting theory that really made me think about my customer's problems first and foremost, and then how Oracle technology can provide answers. As much as I prefer techno-thrillers and sci-fi novels to actuarial papers for plane reading, I got very excited about the idea of putting myself back in the customer shoes I haven't worn in a decade, and really looking at how Oracle can power the Adaptive Insurance Enterprise. Talking to customers and industry people after the session, the idea of Alamere seemed to excite people and I got a lot of suggestions as to what lines of business we should model and where we should focus first on technology uptake. One customer said to a colleague that Oracle's attempt to "share their pain" was unique among vendors. More about Alamere, and the Adaptive Insurance Enterprise next time. Chuck Johnston is vice president of global strategy and alliances for Oracle Insurance.

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  • What are some great papers/publications relating to game programming?

    - by Archagon
    What are some of your favorite papers and publications that closely relate to game programming? I'm particularly looking for examples that are well-written and illustrated, and/or have had a profound influence on the industry. (Here's one example: in this GDC talk, Bungie's David Aldridge mentions that a paper called "The TRIBES Engine Networking Model" was the starting point for Halo's network code.)

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  • Interpolating Matrices

    - by sebf
    Hello, Apologies if I am missing something very obvious (likely!) but is there anything wrong with interpolating between two matrices by: float d = (float)(targetTime.Ticks - keyframe_start.ticks) / (float)(keyframe_end.ticks - keyframe_start.ticks); return ((keyframe_start.Transform * (1 - d)) + (keyframe_end.Transform * d)); As in my app, when I try an use this to interpolate between two keyframes, the model begins to 'shrink' - the severity based on how far between the two keyframes the target time is; its worst when the transform split is ~50/50.

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  • What are the most commonly used enterprise Java technologies, and what would you want a non technical audience to understand about them?

    - by overstood
    I have been asked to give a presentation to a non-technical audience on what Java technologies are currently being used in the enterprise world. The goal is to give this non-technical audience the background they need to understand what engineers are talking about. It's part of a broader series of talks that I'm giving. I'm primarily a .NET and C++ dev, so I thought I'd try to get some input from some Java devs. What technologies do you use? What Java related acronyms would you like to be able to use around non-coders? What would you like non-coders to understand about them?

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  • Presenting Windows Phone 8 at Microsoft Store in Orlando, FL

    - by Nikita Polyakov
    Want to see Windows Phone 8 in person yourself? Want see me present a few features live? Want to come chat in person after? Come by Microsoft Store at The Florida Mall in Orlando, FL on Saturday Nov 17th 2012 at 6-7PM. I will be presenting the Windows Phone 8 OS (no developer content) If you come see this presentation and fill out a survey after you get to be in the drawing for Asus VivoTab RT (see official rules) Let me know if you are coming by! Would love to chat :) Event is also posted on Facebook: https://www.facebook.com/events/167104910079987

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  • Nokia présente son smartphone sous MeeGo, le N9 sera commercialisé dans le courant de l'année

    Nokia présente son smartphone sous MeeGo Le N9 sera commercialisé dans le courant de l'année Pour une bonne surprise, c'est une bonne surprise. Même si le bruit courrait depuis quelques jours. Nokia vient d'annoncer son premier (et certainement unique) smartphone sous MeeGo : le N9. [IMG]http://ftp-developpez.com/gordon-fowler/N9/N93.png[/IMG] La présentation a eu lieu lors du Nokia Connections, le salon de l'entreprise qui se tient actuellement à Singapour. Le N9 se veut « beau et simple » avec des « possibilités infinies ». Simple, il l'est puisque la navigation se fait ex...

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  • 3 Performance Presentations from SAE added to the portal

    - by uwes
    The following three presentation have been added to eSTEP portal: Oracle's Systems Performance Oct 2012 Update Oracle Leads the Way on Realistic Sizing Oracle's Performance: Oracle SPARC SuperCluster All presentations are created by Brad Carlile, Sr. Director Strategic Applications Engineering, SAE. How to get to the presentations: URL: http://launch.oracle.com/ Email Address: <provide your email address>Access URL/Page Token: eSTEP_2011To get access push Agree button on the left side of the page. Click on eSTEP Download (tab band on the top) ---> presentations at right hand side or Click on Miscellaneous (menu on left hand side) ---> presentations at right hand side

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  • Understanding Data Science: Recent Studies

    - by Joe Lamantia
    If you need such a deeper understanding of data science than Drew Conway's popular venn diagram model, or Josh Wills' tongue in cheek characterization, "Data Scientist (n.): Person who is better at statistics than any software engineer and better at software engineering than any statistician." two relatively recent studies are worth reading.   'Analyzing the Analyzers,' an O'Reilly e-book by Harlan Harris, Sean Patrick Murphy, and Marck Vaisman, suggests four distinct types of data scientists -- effectively personas, in a design sense -- based on analysis of self-identified skills among practitioners.  The scenario format dramatizes the different personas, making what could be a dry statistical readout of survey data more engaging.  The survey-only nature of the data,  the restriction of scope to just skills, and the suggested models of skill-profiles makes this feel like the sort of exercise that data scientists undertake as an every day task; collecting data, analyzing it using a mix of statistical techniques, and sharing the model that emerges from the data mining exercise.  That's not an indictment, simply an observation about the consistent feel of the effort as a product of data scientists, about data science.  And the paper 'Enterprise Data Analysis and Visualization: An Interview Study' by researchers Sean Kandel, Andreas Paepcke, Joseph Hellerstein, and Jeffery Heer considers data science within the larger context of industrial data analysis, examining analytical workflows, skills, and the challenges common to enterprise analysis efforts, and identifying three archetypes of data scientist.  As an interview-based study, the data the researchers collected is richer, and there's correspondingly greater depth in the synthesis.  The scope of the study included a broader set of roles than data scientist (enterprise analysts) and involved questions of workflow and organizational context for analytical efforts in general.  I'd suggest this is useful as a primer on analytical work and workers in enterprise settings for those who need a baseline understanding; it also offers some genuinely interesting nuggets for those already familiar with discovery work. We've undertaken a considerable amount of research into discovery, analytical work/ers, and data science over the past three years -- part of our programmatic approach to laying a foundation for product strategy and highlighting innovation opportunities -- and both studies complement and confirm much of the direct research into data science that we conducted. There were a few important differences in our findings, which I'll share and discuss in upcoming posts.

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  • flash video appears blue ubuntu 12.04

    - by pst007x
    This is a duplicate, however the solution given does not work. After updating to Ubuntu 12.04 from Ubuntu 11.10, all video is now blue, whether playing in a browser or a player. I have tried to uninstall all Flash and re-installed but makes no difference. Does anyone have any ideas? Fix (work around) Issue: All web browsers flash player video is blue Chromium Google Chrome Firefox Both flash plugins causes flash video to appear have a blue overlay, so remove. Adobe - flashplugin Flashplugin - installer Solution (not as functional as adobe flash plug in but it works) Install Lightspark (plus any browser-plugins) or Install Gnash (plus any browser-plugins) FIX (Possible) Removed: Gnash-browser plugins Video Decode and Presentation API for Unix (libraries) libvdpau1 Installed: Adobe-flashplugin Re-started browser, and it worked for me.

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  • Dual Monitor (Monitor and TV)

    - by umpirsky
    I connected TV to my computer, and trying to set dual display. Whatever resolution I choose for my second display (TV) I get message like this: The selected configuration for displays could not be applied required virtual size does not fit available size: requested=(2704, 1050), minimum=(320, 200), maximum=(1680, 1680) How can I fix this? Also, while I was experimenting system went to deadlock, I restarted and after boot monitor just turns off once system is up. I boot in recovery mode and after several retries fixed it somehow, I don't know how, probably by changing display config from display manager. now I found xorg.conf.new file in my home dir: Section "ServerLayout" Identifier "X.org Configured" Screen 0 "Screen0" 0 0 Screen 1 "Screen1" RightOf "Screen0" Screen 2 "Screen2" RightOf "Screen1" InputDevice "Mouse0" "CorePointer" InputDevice "Keyboard0" "CoreKeyboard" EndSection Section "Files" ModulePath "/usr/lib/xorg/modules" FontPath "/usr/share/fonts/X11/misc" FontPath "/usr/share/fonts/X11/cyrillic" FontPath "/usr/share/fonts/X11/100dpi/:unscaled" FontPath "/usr/share/fonts/X11/75dpi/:unscaled" FontPath "/usr/share/fonts/X11/Type1" FontPath "/usr/share/fonts/X11/100dpi" FontPath "/usr/share/fonts/X11/75dpi" FontPath "/var/lib/defoma/x-ttcidfont-conf.d/dirs/TrueType" FontPath "built-ins" EndSection Section "Module" Load "extmod" Load "dbe" Load "glx" Load "dri" Load "dri2" Load "record" EndSection Section "InputDevice" Identifier "Keyboard0" Driver "kbd" EndSection Section "InputDevice" Identifier "Mouse0" Driver "mouse" Option "Protocol" "auto" Option "Device" "/dev/input/mice" Option "ZAxisMapping" "4 5 6 7" EndSection Section "Monitor" Identifier "Monitor0" VendorName "Monitor Vendor" ModelName "Monitor Model" EndSection Section "Monitor" Identifier "Monitor1" VendorName "Monitor Vendor" ModelName "Monitor Model" EndSection Section "Monitor" Identifier "Monitor2" VendorName "Monitor Vendor" ModelName "Monitor Model" EndSection Section "Device" ### Available Driver options are:- ### Values: <i>: integer, <f>: float, <bool>: "True"/"False", ### <string>: "String", <freq>: "<f> Hz/kHz/MHz", ### <percent>: "<f>%" ### [arg]: arg optional #Option "NoAccel" # [<bool>] #Option "SWcursor" # [<bool>] #Option "Dac6Bit" # [<bool>] #Option "Dac8Bit" # [<bool>] #Option "BusType" # [<str>] #Option "CPPIOMode" # [<bool>] #Option "CPusecTimeout" # <i> #Option "AGPMode" # <i> #Option "AGPFastWrite" # [<bool>] #Option "AGPSize" # <i> #Option "GARTSize" # <i> #Option "RingSize" # <i> #Option "BufferSize" # <i> #Option "EnableDepthMoves" # [<bool>] #Option "EnablePageFlip" # [<bool>] #Option "NoBackBuffer" # [<bool>] #Option "DMAForXv" # [<bool>] #Option "FBTexPercent" # <i> #Option "DepthBits" # <i> #Option "PCIAPERSize" # <i> #Option "AccelDFS" # [<bool>] #Option "IgnoreEDID" # [<bool>] #Option "CustomEDID" # [<str>] #Option "DisplayPriority" # [<str>] #Option "PanelSize" # [<str>] #Option "ForceMinDotClock" # <freq> #Option "ColorTiling" # [<bool>] #Option "VideoKey" # <i> #Option "RageTheatreCrystal" # <i> #Option "RageTheatreTunerPort" # <i> #Option "RageTheatreCompositePort" # <i> #Option "RageTheatreSVideoPort" # <i> #Option "TunerType" # <i> #Option "RageTheatreMicrocPath" # <str> #Option "RageTheatreMicrocType" # <str> #Option "ScalerWidth" # <i> #Option "RenderAccel" # [<bool>] #Option "SubPixelOrder" # [<str>] #Option "ClockGating" # [<bool>] #Option "VGAAccess" # [<bool>] #Option "ReverseDDC" # [<bool>] #Option "LVDSProbePLL" # [<bool>] #Option "AccelMethod" # <str> #Option "DRI" # [<bool>] #Option "ConnectorTable" # <str> #Option "DefaultConnectorTable" # [<bool>] #Option "DefaultTMDSPLL" # [<bool>] #Option "TVDACLoadDetect" # [<bool>] #Option "ForceTVOut" # [<bool>] #Option "TVStandard" # <str> #Option "IgnoreLidStatus" # [<bool>] #Option "DefaultTVDACAdj" # [<bool>] #Option "Int10" # [<bool>] #Option "EXAVSync" # [<bool>] #Option "ATOMTVOut" # [<bool>] #Option "R4xxATOM" # [<bool>] #Option "ForceLowPowerMode" # [<bool>] #Option "DynamicPM" # [<bool>] #Option "NewPLL" # [<bool>] #Option "ZaphodHeads" # <str> Identifier "Card0" Driver "radeon" BusID "PCI:2:0:0" EndSection Section "Device" ### Available Driver options are:- ### Values: <i>: integer, <f>: float, <bool>: "True"/"False", ### <string>: "String", <freq>: "<f> Hz/kHz/MHz", ### <percent>: "<f>%" ### [arg]: arg optional #Option "ShadowFB" # [<bool>] #Option "Rotate" # <str> #Option "fbdev" # <str> #Option "debug" # [<bool>] Identifier "Card1" Driver "fbdev" BusID "PCI:2:0:0" EndSection Section "Device" ### Available Driver options are:- ### Values: <i>: integer, <f>: float, <bool>: "True"/"False", ### <string>: "String", <freq>: "<f> Hz/kHz/MHz", ### <percent>: "<f>%" ### [arg]: arg optional #Option "ShadowFB" # [<bool>] #Option "DefaultRefresh" # [<bool>] #Option "ModeSetClearScreen" # [<bool>] Identifier "Card2" Driver "vesa" BusID "PCI:2:0:0" EndSection Section "Screen" Identifier "Screen0" Device "Card0" Monitor "Monitor0" SubSection "Display" Viewport 0 0 Depth 1 EndSubSection SubSection "Display" Viewport 0 0 Depth 4 EndSubSection SubSection "Display" Viewport 0 0 Depth 8 EndSubSection SubSection "Display" Viewport 0 0 Depth 15 EndSubSection SubSection "Display" Viewport 0 0 Depth 16 EndSubSection SubSection "Display" Viewport 0 0 Depth 24 EndSubSection EndSection Section "Screen" Identifier "Screen1" Device "Card1" Monitor "Monitor1" SubSection "Display" Viewport 0 0 Depth 1 EndSubSection SubSection "Display" Viewport 0 0 Depth 4 EndSubSection SubSection "Display" Viewport 0 0 Depth 8 EndSubSection SubSection "Display" Viewport 0 0 Depth 15 EndSubSection SubSection "Display" Viewport 0 0 Depth 16 EndSubSection SubSection "Display" Viewport 0 0 Depth 24 EndSubSection EndSection Section "Screen" Identifier "Screen2" Device "Card2" Monitor "Monitor2" SubSection "Display" Viewport 0 0 Depth 1 EndSubSection SubSection "Display" Viewport 0 0 Depth 4 EndSubSection SubSection "Display" Viewport 0 0 Depth 8 EndSubSection SubSection "Display" Viewport 0 0 Depth 15 EndSubSection SubSection "Display" Viewport 0 0 Depth 16 EndSubSection SubSection "Display" Viewport 0 0 Depth 24 EndSubSection EndSection Can I delete it? Second display (TV) only works when I check Mirror displays option.

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  • PASS Summit 2011 &ndash; Part III

    - by Tara Kizer
    Well we’re about a month past PASS Summit 2011, and yet I haven’t finished blogging my notes! Between work and home life, I haven’t been able to come up for air in a bit.  Now on to my notes… On Thursday of the PASS Summit 2011, I attended Klaus Aschenbrenner’s (blog|twitter) “Advanced SQL Server 2008 Troubleshooting”, Joe Webb’s (blog|twitter) “SQL Server Locking & Blocking Made Simple”, Kalen Delaney’s (blog|twitter) “What Happened? Exploring the Plan Cache”, and Paul Randal’s (blog|twitter) “More DBA Mythbusters”.  I think my head grew two times in size from the Thursday sessions.  Just WOW! I took a ton of notes in Klaus' session.  He took a deep dive into how to troubleshoot performance problems.  Here is how he goes about solving a performance problem: Start by checking the wait stats DMV System health Memory issues I/O issues I normally start with blocking and then hit the wait stats.  Here’s the wait stat query (Paul Randal’s) that I use when working on a performance problem.  He highlighted a few waits to be aware of such as WRITELOG (indicates IO subsystem problem), SOS_SCHEDULER_YIELD (indicates CPU problem), and PAGEIOLATCH_XX (indicates an IO subsystem problem or a buffer pool problem).  Regarding memory issues, Klaus recommended that as a bare minimum, one should set the “max server memory (MB)” in sp_configure to 2GB or 10% reserved for the OS (whichever comes first).  This is just a starting point though! Regarding I/O issues, Klaus talked about disk partition alignment, which can improve SQL I/O performance by up to 100%.  You should use 64kb for NTFS cluster, and it’s automatic in Windows 2008 R2. Joe’s locking and blocking presentation was a good session to really clear up the fog in my mind about locking.  One takeaway that I had no idea could be done was that you can set a timeout in T-SQL code view LOCK_TIMEOUT.  If you do this via the application, you should trap error 1222. Kalen’s session went into execution plans.  The minimum size of a plan is 24k.  This adds up fast especially if you have a lot of plans that don’t get reused much.  You can use sys.dm_exec_cached_plans to check how often a plan is being reused by checking the usecounts column.  She said that we can use DBCC FLUSHPROCINDB to clear out the stored procedure cache for a specific database.  I didn’t know we had this available, so this was great to hear.  This will be less intrusive when an emergency comes up where I’ve needed to run DBCC FREEPROCCACHE. Kalen said one should enable “optimize for ad hoc workloads” if you have an adhoc loc.  This stores only a 300-byte stub of the first plan, and if it gets run again, it’ll store the whole thing.  This helps with plan cache bloat.  I have a lot of systems that use prepared statements, and Kalen says we simulate those calls by using sp_executesql.  Cool! Paul did a series of posts last year to debunk various myths and misconceptions around SQL Server.  He continues to debunk things via “DBA Mythbusters”.  You can get a PDF of a bunch of these here.  One of the myths he went over is the number of tempdb data files that you should have.  Back in 2000, the recommendation was to have as many tempdb data files as there are CPU cores on your server.  This no longer holds true due to the numerous cores we have on our servers.  Paul says you should start out with 1/4 to 1/2 the number of cores and work your way up from there.  BUT!  Paul likes what Bob Ward (twitter) says on this topic: 8 or less cores –> set number of files equal to the number of cores Greater than 8 cores –> start with 8 files and increase in blocks of 4 One common myth out there is to set your MAXDOP to 1 for an OLTP workload with high CXPACKET waits.  Instead of that, dig deeper first.  Look for missing indexes, out-of-date statistics, increase the “cost threshold for parallelism” setting, and perhaps set MAXDOP at the query level.  Paul stressed that you should not plan a backup strategy but instead plan a restore strategy.  What are your recoverability requirements?  Once you know that, now plan out your backups. As Paul always does, he talked about DBCC CHECKDB.  He said how fabulous it is.  I didn’t want to interrupt the presentation, so after his session had ended, I asked Paul about the need to run DBCC CHECKDB on your mirror systems.  You could have data corruption occur at the mirror and not at the principal server.  If you aren’t checking for data corruption on your mirror systems, you could be failing over to a corrupt database in the case of a disaster or even a planned failover.  You can’t run DBCC CHECKDB against the mirrored database, but you can run it against a snapshot off the mirrored database.

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  • Best way to relate code smells to a non technical audience?

    - by Ed Guiness
    I have been asked to present examples of code issues that were found during a code review. My audience is mostly non-technical and I want to try to express the issues in such a way that I convey the importance of "good code" versus "bad code". But as I review my presentation it seems to me I've glossed over the reasons why it is important to write good code. I've mentioned a number of reasons including ease of maintenance, increased likelihood of bugs, but with my "non tech" hat on they seem unconvincing. What is your advice for helping a non-technical audience relate to the importance of good code?

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  • NUMA-aware placement of communication variables

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

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  • Congratulations to the 2012 Oracle Spatial Award Winners!

    - by Mandy Ho
    I just returned from the 2012 Location Intelligence and Oracle Spatial User conference in Washington, DC, held by Directions Magazine. It was a great conference with presentations from across the country and globe, networking with Oracle Spatial users and meeting new customers and partners. As part of the yearly event, Oracle recognizes special customers and partners for their contributions to advancing mainstream solutions using geospatial technology. This was the 8th year that Oracle has recognized innovative, industry leaders.   The awards were given in three categories: Education/Research, Innovator and Partnership. Here's a little on each of the award winners. Education and Research Award Winner: Technical University of Berlin The Institute for Geodesy and Geoinformation Science of the Technical University of Berlin (TU Berlin) was selected for its leading research work in mapping of urban and regional space onto virtual 3D-city and landscape models, and use of Oracle Spatial, including 3D Vector and Georaster type support, as the data management platform. Innovator Award Winner:  Istanbul Metropolitan Municipality Istanbul is the 3rd largest metropolitan area in Europe. One of their greatest challenges is organizing efficient public transportation for citizens and visitors. There are 15 types of transportations organized by 8 different agencies. To solve this problem, the Directorate of GIS of Istanbul Metropolitan Municipality has created a multi-model itinerary system to help citizens in their decision process for using public transport or their private cars. They choose to use Oracle Spatial Network Model as the solution in our system together with Java and SOAP web services.  Partnership Award Winners: CSoft Group and OSCARS. The Partnership award is given to the ISV or integrator who have demonstrated outstanding achievements in partnering with Oracle on the development side, in taking solutions to market.  CSoft Group- the largest Russion integrator and consultancy provider in CAD and GIS. CSoft was selected by the Oracle Spatial product development organization for the key role in delivering geospatial solutions based on Oracle Database and Fusion Middleware to the Russian market. OSCARS - Provides consulting/training in France, Belgium and Luxembourg. With only 3 full time staff, they have achieved significant success with leading edge customer implementations leveraging the latest Oracle Spatial/MapViewer technologies, and delivering training throughout Europe.  Finally, we also awarded two Special Recognition awards for two partners that helped contribute to the Oracle Partner Network Spatial Specialization. These two partners provided insight and technical expertise from a partner perspective to help launch the new certification program for Oracle Spatial Technologies. Award Winners: ThinkHuddle and OSCARS  For more pictures on the conference and the awards, visit our facebook page: http://www.facebook.com/OracleDatabase

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  • Infrastructure and Platform As A Service in Private Cloud at Lawrence Livermore National Laboratory

    - by Anand Akela
    Scientists at the National Ignition Facility (NIF)— the world’s largest laser, at the Lawrence Livermore National Laboratory (LLNL)— need research environment that requires re-creating the physical environment and conditions that exist inside the sun. They have built private cloud infrastructure using Oracle VM and Oracle Enterprise Manager 12c to provision such an environment for research.  Tim Frazier of LLNL joined the "Managing Your Private Cloud With Oracle Enterprise Manager' session at Oracle Open World 2012 and discussed how the latest features in Oracle VM and Oracle Enterprise Manager 12c enables them to accelerate application provisioning in their private cloud. He also talked about how to increase service delivery agility, improve standardized roll outs, and do proactive management to gain total control of the private cloud environment. He also presented at the "Scene and Be Heard Theater" at Oracle OpenWorld 2012 and shared a lot of good information about his project and what they are doing in their private cloud environment. Learn more by looking at Tim's presentation .

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  • OpenGL 2.1+ Render with data returned form assimp library

    - by Bình Nguyên
    I have just readed this tutorial about load a 3D model file: http://www.lighthouse3d.com/cg-topics/code-samples/importing-3d-models-with-assimp/#comment-14551. Its render routine uses a recursive_render function to scan all node. My question: What is a aiNode struct store? What different form this method and above method: for (int i=0; imNumMesh; ++i) { draw scene-mMeshes[i]; } Thanks for reading!

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  • Unit testing in Django

    - by acjohnson55
    I'm really struggling to write effective unit tests for a large Django project. I have reasonably good test coverage, but I've come to realize that the tests I've been writing are definitely integration/acceptance tests, not unit tests at all, and I have critical portions of my application that are not being tested effectively. I want to fix this ASAP. Here's my problem. My schema is deeply relational, and heavily time-oriented, giving my model object high internal coupling and lots of state. Many of my model methods query based on time intervals, and I've got a lot of auto_now_add going on in timestamped fields. So take a method that looks like this for example: def summary(self, startTime=None, endTime=None): # ... logic to assign a proper start and end time # if none was provided, probably using datetime.now() objects = self.related_model_set.manager_method.filter(...) return sum(object.key_method(startTime, endTime) for object in objects) How does one approach testing something like this? Here's where I am so far. It occurs to me that the unit testing objective should be given some mocked behavior by key_method on its arguments, is summary correctly filtering/aggregating to produce a correct result? Mocking datetime.now() is straightforward enough, but how can I mock out the rest of the behavior? I could use fixtures, but I've heard pros and cons of using fixtures for building my data (poor maintainability being a con that hits home for me). I could also setup my data through the ORM, but that can be limiting, because then I have to create related objects as well. And the ORM doesn't let you mess with auto_now_add fields manually. Mocking the ORM is another option, but not only is it tricky to mock deeply nested ORM methods, but the logic in the ORM code gets mocked out of the test, and mocking seems to make the test really dependent on the internals and dependencies of the function-under-test. The toughest nuts to crack seem to be the functions like this, that sit on a few layers of models and lower-level functions and are very dependent on the time, even though these functions may not be super complicated. My overall problem is that no matter how I seem to slice it, my tests are looking way more complex than the functions they are testing.

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  • BenkoTips Live and On Demand: Visual Studio 2010, Silverlight 4, and WCF (Level 200)

    In this webcast, we explore what's new and possible with Windows Communication Foundation (WCF) RIA Services and your Microsoft Silverlight application. We show how you can create an entity model and then expose it to your client application and how to build a compelling interface using the data-binding features built into Microsoft Visual Studio 2010....Did you know that DotNetSlackers also publishes .net articles written by top known .net Authors? We already have over 80 articles in several categories including Silverlight. Take a look: here.

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  • Using Oracle BPM to Extend Oracle Applications

    - by Michelle Kimihira
    Author: Srikant Subramaniam, Senior Principal Product Manager, Oracle Fusion Middleware Customers often modify applications to meet their specific business needs - varying regulatory requirements, unique business processes, product mix transition, etc. Traditional implementation practices for such modifications are typically invasive in nature and introduce risk into projects, affect time-to-market and ease of use, and ultimately increase the costs of running and maintaining the applications. Another downside of these traditional implementation practices is that they literally cast the application in stone, making it difficult for end-users to tailor their individual work environments to meet specific needs, without getting IT involved. For many businesses, however, IT lacks the capacity to support such rapid business changes. As a result, adopting innovative solutions to change the economics of customization becomes an imperative rather than a choice. Let's look at a banking process in Siebel Financial Services and Oracle Policy Automation (OPA) using Oracle Business Process Management. This approach makes modifications simple, quick to implement and easy to maintain/upgrade. The process model is based on the Loan Origination Process Accelerator, i.e., a set of ready to deploy business solutions developed by Oracle using Business Process Management (BPM) 11g, containing customizable and extensible pre-built processes to fit specific customer requirements. This use case is a branch-based loan origination process. Origination includes a number of steps ranging from accepting a loan application, applicant identity and background verification (Know Your Customer), credit assessment, risk evaluation and the eventual disbursal of funds (or rejection of the application). We use BPM to model all of these individual tasks and integrate (via web services) with: Siebel Financial Services and (simulated) backend applications: FLEXCUBE for loan management, Background Verification and Credit Rating. The process flow starts in Siebel when a customer applies for loan, switches to OPA for eligibility verification and product recommendations, before handing it off to BPM for approvals. OPA Connector for Siebel simplifies integration with Siebel’s web services framework by saving directly into Siebel the results from the self-service interview. This combination of user input and product recommendation invokes the BPM process for loan origination. At the end of the approval process, we update Siebel and the financial app to complete the loop. We use BPM Process Spaces to display role-specific data via dashboards, including the ability to track the status of a given process (flow trace). Loan Underwriters have visibility into the product mix (loan categories), status of loan applications (count of approved/rejected/pending), volume and values of loans approved per processing center, processing times, requested vs. approved amount and other relevant business metrics. Summary Oracle recommends the use of Fusion Middleware as an extensions platform for applications. This approach makes modifications simple, quick to implement and easy to maintain/upgrade applications (by moving customizations away from applications to the process layer). It is also easier to manage processes that span multiple applications by using Oracle BPM. Additional Information Product Information on Oracle.com: Oracle Fusion Middleware Follow us on Twitter and Facebook Subscribe to our regular Fusion Middleware Newsletter

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  • Why it is so difficult to find a good Ads SDK for Windows Phone 7

    - by help.net
    This post try to address an issue with the Microsoft Advertising SDK, the main fact that today Microsoft is still refusing access to the Ad Center worldwide. Yesterday they generously increase the number of free apps we can develop from 5 to 100. According to talks with other developers and the Windows Phone 7 team, I have the strong feeling the model of publishing free apps supported by apps is the right course to take today. This probably why Microsoft has moved to a bigger figure. Am I the only...(read more)

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  • Warp GameObject Size When Entering/Leaving Area

    - by Julian
    Below I have an image describing the desired functionality I am going for. Let's say you control a square and when you move this square into a given area, any part of your rigidbody/model inside of the area will be magnified upon entering and shrunk upon leaving. So now you more or less are made up of two rectangles, one small and one large. What would be an elegant approach towards achieving this effect?

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