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• Solar Power Your Data Center Into the Future

  Hard-Core Hardware: The age of solar power is fast arriving, and it may be keeping the lights on in a data center near you. The former downsides, chiefly cost constraints, no longer apply.

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• Add a Flight Full of Color to Your Desktop with the Beautiful Birds Theme for Windows 7

  - by Asian Angel

  Do you enjoy looking at and collecting pictures of beautifully colored birds? Then brighten up your desktop with the grace and gorgeous plumage of swans, flamingoes, peacocks, and other exotic birds with this wonderful theme for Windows 7. Note: The theme comes with seventeen awesome wallpapers full of brightly colored avian goodness. Download the Beautiful Birds Theme [Windows 7 Personalization Gallery] How To Encrypt Your Cloud-Based Drive with BoxcryptorHTG Explains: Photography with Film-Based CamerasHow to Clean Your Dirty Smartphone (Without Breaking Something)

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• Did You Know Gaming Delves into the Mario Universe [Video]

  - by Jason Fitzpatrick

  If you thought you knew everything there was to know about the Mario franchise, prepare to be surprised by the odd and expansive trivia dug up by Did You Know Gaming. Who knew you could learn so much about a game by picking through the game code for odds and ends? If you enjoyed the above video, make sure to check out Part II here. [via Geeks Are Sexy] 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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• Finally, I have my HP 6910p laptop running with 8Gb RAM

  - by Liam Westley

  Today, I received two Corsair Value Select 4Gb DDR SO-DIMMs (from overclock.co.uk) for my aging HP 6910p to give it the extra lease of life to keep it going until the end of 2010.  And here is the proof that Windows 7 64-bit happily sees all 8Gb, There are no 4Gb modules are officially supported for the HP 6910p (they didn’t exist when it was first build).  I was taking a bit of a gamble, and relying on the UK distance selling regulations which meant that even if they didn’t work I’d be able to send them back, getting a full refund and only paying for the return postage. I’d read Keith Comb’s blog back in 2008, (http://blogs.technet.com/b/keithcombs/archive/2008/07/05/loading-a-hp-6910p-with-8gb-of-ram.aspx) where he mentioned ‘trying’ out 4Gb samples of SO-DIMMs in a HP 6910p laptop, but there still appears to be no mentions of running this configuration in any other blog. Seeing how the 8Gb of memory is used is made easier with the new Resource Monitor available in Windows 7.  With two copies of Visual Studio 2008, Outlook, Firefox (with 30+ tabs), TweetDeck (an infamous memory hog) and VMWare workstation running a virtual machine allocated with 2Gb of memory, you might have no ‘free’ memory remaining, but the standby memory is an awesome 2.4Gb, and once the VM is up and running the Hard Faults/sec hovers around zero,   It’s the page fault figure which really counts, because reducing that value means that you are preventing the Windows 7 system drive from being used for virtual memory paging operations.  Even after only a few hours of use it’s noticeable that disc access has been reduced and applications feel more responsive and ‘snappy’.  I did consider the option of purchasing an SSD to replace the main drive, rather than go for 8Gb of RAM, but I think I’ve probably made the correct decision. Given my hobby topic of virtualisation, I take the view that you can never have too much memory.   It was also a decision made easier by the price differential between 8Gb of RAM compared to a decent size SSD.  In the 18 months since Keith Comb tested the first 4Gb SO-DIMMS they have plummeted in price, at just under £100 per 4Gb, they are around a fifth of the price when launched. So if you ever wondered if a HP 6910p can handle 8Gb, now you know.

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• Sharp Architecture 1.9.5 Released

  - by AlecWhittington

  The S#arp Architecture team is proud to announce the release of version 1.9.5. This version has had the following changes: Upgraded to MVC 3 RTM Solution upgraded to .NET 4 Implementation of IDependencyResolver provided, but not implemented This marks the last scheduled release of 1.X for S#arp Architecture . The team is working hard to get the 2.0 release out the door and we hope to have a preview of that coming soon. With regards to IDependencyResolver, we have provided an implementation, but have...(read more)

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• OP-ED: Software Development from Core to Cosmetics

  Few projects end up having too much time. Successfully completing a project often depends on tackling core, significant, and risky aspects of any custom solution first&mdash;like the long hard march up hill&mdash;and finishing with the trim, or cosmetic work, last.

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• Good design cannot be over-design

  - by ??? Shengyuan Lu

  Many engineers intend to design software to build "flexible" system in which many design patterns and interfaces there. Eventually too many interfaces and complex inheritances mess up the system. In most cases I think the improper design caused the mess, rather than not over-design. If design is reasonable, it's hard to be over. Alternatively, If we don't have enough skill to achieve flexible design, we choose to plain and practical design. What's your opinion about my understanding?

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• PeopleSoft HCM @ OHUG 11: Enter the Matrix

  - by Jay Zuckert

  The PeopleSoft HCM team is back from a very busy and exciting OHUG conference in Orlando. The packed, standing-room only PeopleSoft HCM Roadmap keynote was the highlight of the conference for many attendees and the reviews are in : PeopleSoft rocked the house ! Great demonstration of products in the keynote. Best keynote in a long time, and fun. Engaging and entertaining, great demonstration of capabilities. Message received loud and clear, PeopleSoft applications are here to stay.  PeopleSoft has a real vision moving forward. Real-time polls using mobile texting were cutting edge.                          Tracy Martin (as Trinity) and other members of the PeopleSoft HCM team presented a ‘must-see’ Matrix-themed session while dressed as movie characters. The keynote highlighted planned HCM capabilities for Matrix administration and future organization visualization enhancements. The team also previewed the planned Manager Dashboard and Talent Summary.                           Following the keynote, some of the cast posed for photo opportunities at the OHUG booth in the exhibition hall. As you can imagine, they received some interesting looks walking by the other vendor booths. The PeopleSoft HCM team also presented numerous other OHUG sessions covering PeopleSoft Talent Management, Compensation, HR HelpDesk, Payroll, Global HCM Practices, Time & Labor, Absence Management, and Benefits. All of those presentations are available from the OHUG site at www.ohug.org. When not in one of the well-attended PeopleSoft HCM sessions, conference attendees filled the Oracle booth in the exhibition hall to see live product demonstrations. True to their PeopleSoft roots, some of the PeopleSoft HCM team played as hard as they worked in Orlando and enjoyed the OHUG Appreciation event along with customers at the Hard Rock. We are already busy planning for Oracle OpenWorld 2011 and prepping sessions our PeopleSoft HCM customers are sure to like. We hope to see you there in San Francisco from Oct. 2-6. To learn more about OpenWorld or to register, click here.

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• Friday Fun: Shape Fold

  - by Asian Angel

  This week’s game comes with lots of puzzle solving, brain-teasing goodness to keep you busy. On each level you will need to rotate, twist, and/or move the hinged puzzle pieces into their proper shape. Do you have the patience and skill to solve all the puzzles or will you be forced to admit defeat? 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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• All-in-one PC has dual-core Atom

  <b>Desktop Linux:</b> "Shuttle announced a compact, all-in-one PC featuring a 15.6-inch touchscreen and a dual-core Intel Atom D510 available with SUSE Linux. The X50V2 includes a 1366 x 768 display, webcam, 4-in-1 card reader, a 2.5-inch hard drive bay, and up to 4GB of RAM, says the company."

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• Launch Invitation: Introducing Oracle WebLogic Server 12c

  - by JuergenKress

  Introducing Oracle WebLogic Server 12c, the #1 Application Server Across Conventional and Cloud Environments Please join Hasan Rizvi on December 1, as he unveils the next generation of the industry’s #1 application server and cornerstone of Oracle’s cloud application foundation—Oracle WebLogic Server 12c. Hear, with your fellow IT managers, architects, and developers, how the new release of Oracle WebLogic Server is: Designed to help you seamlessly move into the public or private cloud with an open, standards-based platform Built to drive higher value for your current infrastructure and significantly reduce development time and cost Optimized to run your solutions for Java Platform, Enterprise Edition (Java EE); Oracle Fusion Middleware; and Oracle Fusion Applications Enhanced with transformational platforms and technologies such as Java EE 6, Oracle’s Active GridLink for RAC, Oracle Traffic Director, and Oracle Virtual Assembly Builder Don’t miss this online launch event. Register now. Executive Overview Thurs., December 1, 2011 10 a.m. PT / 1 p.m. ET Presented by: Hasan Rizvi Senior Vice President, Product Development, Oracle Today most businesses have the ambition to move to a cloud infrastructure. However, IT needs to maintain and invest in their current infrastructure for supporting today’s business. With Oracle WebLogic, the #1 app server in the marketplace, we provide you with the best of both worlds. The enhancements contained in WebLogic 12c provide you with significant benefits that drive higher value for your current infrastructure, while significantly reducing development time and cost. In addition, with WebLogic you are cloud-ready. You can move your existing applications as-is to a high performance engineered system, Exalogic, and instantly experience performance and scalability improvements that are orders of magnitude higher. A WebLogic-Exalogic combination may provide your private cloud infrastructure. Moreover, you can develop and test your applications on the recently announced Oracle’s Public Cloud offering: the Java Cloud Service and seamlessly move these to your on-premise infrastructure for production deployments. Developer Deep-Dive Thurs., December 1, 2011 11 a.m. PT / 2 p.m. ET See demos and interact with experts via live chat. Presented by: Will Lyons Director, Oracle WebLogic Server Product Management, Oracle Modern Java development looks very different from even a few years ago. Technology innovation, the ecosystem of tools and their integration with Java standards are changing how development is done. Cloud Computing is causing developers to re-evaluate their development platforms and deployment options. Business users are demanding faster time to market, but without sacrificing application performance and reliability. Find out in this session how Oracle WebLogic Server 12c enables rapid development of modern, lightweight Java EE 6 applications. Learn how you can leverage the latest development technologies, tools and standards when deploying to Oracle WebLogic Server across both conventional and Cloud environments. Don’t miss this online launch event. Register now. For regular information become a member of the WebLogic Partner Community please register at http://www.oracle.com/partners/goto/wls-emea Blog Twitter LinkedIn Mix Forum Wiki Technorati Tags: Hasan Rizvi,Oracle,WebLogic 12c,OPN,WebLogic Community,Jürgen Kress

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• VS.NET 2010 SP1, Win 7, Parallels, and a MBP&ndash;Hell, my friends&hellip;HELL!

  - by D'Arcy Lussier

  LightSwitch Beta 2 is out. That’s how all this started. All I wanted was to install it on my MBP’s Win7 Parallels VM. But as I’m finding with running a Win7 VM on a MBP, nothing is as easy as it should be. First my MBP froze during the SP1 installation. Not my VM crashing, the entire machine freezing…no mouse, nothing. Had to do a hard reset. BLECH. Then we’re back and I try to re-install SP1 (since the first try obviously failed). I get met with a dialog asking me where silverlight_sdk.msi was. It was *nowhere*! So I hit the net and download it from Microsoft’s site. Unfortunately, it only downloads an exe and not the individual files which would include the msi. Here’s what I did: - Download the tools for Silverlight 4 (http://www.microsoft.com/downloads/en/details.aspx?FamilyID=b3deb194-ca86-4fb6-a716-b67c2604a139&displaylang=en) - Run it, but don’t hit the install or next button when the dialog comes up - Look in your file structure for a folder with a weird name…bunch of numbers and letters. This is a temp folder that the exe creates and dumps all the necessary setup files into, and clears away after its done. - Inside this folder you’ll find the silverlight_sdk.msi (hooray!). Just copy it to a different location on the C drive. You can then cancel installation. Ok, so that takes care of that…but then running the SP1 installer I get hit with *another* dialog asking for the WCF RIA Services SP1 msi. Now it looks like this MSI is part of the Silverlight Tools package because you’ll see the MSI, but the VS.NET 2010 SP1 installer will thumb its nose at this unworthy msi…for whatever reason. So instead, go here: http://www.silverlight.net/getstarted/riaservices/ …and click on the “Install WCF Ria Services Sp1…” option. This downloads the msi, which you should save to your C drive and direct the VS.NET 2010 SP1 installer to. Then, if you’ve done all that, been good all year, and not made any little children cry, you *might* just be able to install VS.NET 2010 SP1 on your Parallels VM. If you were playing that “Take a shot every time he writes VS.NET 2010 Sp1” drinking game, then you’re drunk…which is a better place to be than where I am right now: watching the installation progress bar slowly creep to completion, hoping there’s no more surprises in store. D

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• Google I/O 2011: HTML5 versus Android: Apps or Web for Mobile Development?

  Google I/O 2011: HTML5 versus Android: Apps or Web for Mobile Development? Reto Meier, Michael Mahemoff Native apps or mobile web? It's often a hard choice when deciding where to invest your mobile development resources. While the mobile web continues to grow, native apps and App Stores are incredibly popular. We will present both perspectives in an app development smackdown. From: GoogleDevelopers Views: 13367 73 ratings Time: 01:01:35 More in Science & Technology

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• Oracle Tutor: Are Documented Policies and Procedures Necessary?

  - by emily.chorba(at)oracle.com

  People refer to policies and procedures with a variety of expressions including business process documentation, standard operating procedures (SOPs), department operating procedures (DOPs), work instructions, specifications, and so on. For our purpose here, policies and procedures mean a set of documents that describe an organization's policies (rules) for operation and the procedures (containing tasks performed by individuals) to fulfill the policies. When an organization documents policies and procedures properly, they can be the strategic link between an organization's vision and its daily operations. Policies and procedures are often necessary because of some external requirement, such as environmental compliance or other governmental regulations. One example of an external requirement would be the American Sarbanes-Oxley Act, requiring full openness in accounting practices. Here are a few other examples of business issues that necessitate writing policies and procedures: Operational needs -- policies and procedures ensure fundamental processes are performed in a consistent way that meets the organization's needs. Risk management -- policies and procedures are identified by the Committee of Sponsoring Organizations of the Treadway Commission (COSO) as a control activity needed to manage risk. Continuous improvement -- Procedures can improve processes by building important internal communication practices. Compliance -- Well-defined and documented processes (i.e. procedures, training materials) along with records that demonstrate process capability can demonstrate an effective internal control system compliant with regulations and standards. In addition to helping with the above business issues, policies and procedures can support the basic needs of employees and management. Well documented and easy to access policies and procedures: allow employees to understand their roles and responsibilities within predefined limits and to stay on the accepted path indentified by the organization's management provide clarity to the reader when dealing with accountability issues or activities that are of critical importance allow management to guide operations without constant intervention allow managers to control events in advance and prevent employees from making costly mistakes Can you think of another way organizations can meet the above needs of management and their employees in place of documented Policies and Procedures? Probably not, but we would love your feedback on this question. And that my friends, is why documented policies and procedures are very necessary. Learn MoreFor more information about Tutor, visit Oracle.com or the Tutor Blog. Post your questions at the Tutor Forum. Emily ChorbaPrinciple Product Manager Oracle Tutor & BPM

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• Is there a tool to do round trip software engineering between a sequence diagram and a group of objects that message back and forth?

  - by DeveloperDon

  Is there a tool to do round trip software engineering between a sequence diagram and a group of objects that message back and forth? Perhaps this seems a little exotic, but it seems like a function that includes message calls or even method invocations on other objects could be automatically converted to a sequence diagram given that it is not hard to do manually. Similarly, when a sequence diagram is modified, based on the message name and type of message, should it not be possible to add a message or method to the calling object?

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• Silverlight Cream for June 10, 2010 -- #879

  - by Dave Campbell

  In this Issue: Emiel Jongerius, Nokola, Christian Schormann, Tim Heuer, David Poll, Mike Snow(-2-), John Papa, and Charles Petzold. Shoutout: Viktor Larsson has a frank look at WP7 based on information from MIX10 and what was said this week in his post: Licking Windows Phone 7... yeah licking, not liking :) .. my guess is even that didn't allow him to keep it! If you haven't already noticed, the CodeProject reader's choice awards are out this week and Telerik won for their RadColorPicker and RadCalendar for Silverlight Telerik also needs congratulations for winning Telerik wins “Best of TechEd” award in the “Components and Middleware” category... check out that trophy... Steven Forte has a picture up of the Telerikers after getting the award. Koen Zwikstra has a new release of Silverlight Spy up that supports the latest release: Silverlight Spy 3.0.0.12 From SilverlightCream.com: Localization of XAML files in Silverlight Emiel Jongerius is back with another post, this time discussing Localizing XAM files... external links and source included. Coolest Silverlight Sound Library for Games I've Seen Yet Nokola talks up a Sound Library for Silverlight 4 Games ... and has links to a great demo, plus the source. SketchFlow: Firing Actions when a Storyboard is Complete Christian Schormann responded to some Twitter questions and demonstrates using the StoryboardCompleted trigger with a Navigate action. Hosting cross-domain Silverlight applications (XAP) Tim Heuer responds to a question from a reader and demonstrates how to host a XAP from a domain other than the one you're working on. Taking Microsoft Silverlight 4 Applications Beyond the Browser (TechEd WEB313) David Poll has all his material up from his TechEd presentation earlier this week on Silverlight OOB... and he covered some pretty extensive material ... check it out! Silverlight Tip of the Day #29 – Configuring Service Reference to Back to LocalHost Mike Snow has a couple new tips up... this first one is quick, but very useful... how to switch your service reference back to localhost without pulling out your hair. Silverlight Tip of the Day #30 – Sending Email from Silverlight In Mike Snow's latest tip, he shows how to send email from your Silverlight app... using a WCF service... and a step-by-step set of instructions. Creating Rich Interactions Using Blend 4: Transition Effects, Fluid Layout and Layout States (Silverlight TV #32) John Papa has Silverlight TV #32 up, and he's talking with Kenny Young of the Expression Blend team while Kenny uses some built-om effects and also creates some impressive examples from scratch -- code included. Simulating Touch Inertia on Windows Phone 7 Charles Petzold has a post up on simulating inertia on WP7... demos in WPF and then moves into WP7... math, source, and external links. Stay in the 'Light! Twitter SilverlightNews | Twitter WynApse | WynApse.com | Tagged Posts | SilverlightCream Join me @ SilverlightCream | Phoenix Silverlight User Group Technorati Tags: Silverlight    Silverlight 3    Silverlight 4    Windows Phone MIX10

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• How To Use Regular Expressions for Data Validation and Cleanup

  You need to provide data validation at the server level for complex strings like phone numbers, email addresses, etc. You may also need to do data cleanup / standardization before moving it from source to target. Although SQL Server provides a fair number of string functions, the code developed with these built-in functions can become complex and hard to maintain or reuse. The Future of SQL Server Monitoring "Being web-based, SQL Monitor 2.0 enables you to check on your servers from almost any location" Jonathan Allen.Try SQL Monitor now.

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• 12/12 Live Webcast: Introducing Next-Generation Enterprise Auditing and Database Firewall

  - by jgelhaus

  Join Oracle Security gurus to hear how Oracle products monitor Oracle and non-Oracle database traffic, detect unauthorized activity including SQL injection attacks, and block internal and external threats from reaching the database. Hear how organizations such as TransUnion Interactive and SquareTwo Financial rely on Oracle to monitor and secure their Oracle and non-Oracle database environments. Register for the webcast here.

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• chrome os in triple boot with ubuntu (elemntary os)(ubuntu gnome) and windows 8.1

  - by Aniel Arias

  hi im wondering how to put/ install chrome os n hard drive with dual boot with Ubuntu and windows 8.1 please i need help with this. i had follow some guides from here https://sites.google.com/site/installationubuntu/chrome-os/make-your-own-chromium-os-notebook and http://unix.stackexchange.com/questions/29283/install-chromium-os-without-usb-disk please contact me at Facebook aniel arias or my email [email protected] thank you

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• Water Balloons In Slow Motion [Video]

  - by Jason Fitzpatrick

  As part of our ongoing campaign to prove that everything looks better in slow motion, we present to you: ultra slow motion footage of rippling water balloons. [via Boing Boing] HTG Explains: How Windows Uses The Task Scheduler for System Tasks HTG Explains: Why Do Hard Drives Show the Wrong Capacity in Windows? Java is Insecure and Awful, It’s Time to Disable It, and Here’s How

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• Consider GlassFish ESB v2 for SOA Tooling

  Are you finding it hard to obtain funding to finish building out your Service Oriented Architecture (SOA) technology stack? You may have heard about the Open Source GlassFish Java 5 EE Application Server, but did you know that there is a GlassFish ESB (Enterprise Service Bus) Project that integrates the Open ESB Project? See what it can do for you.

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• A Good .NET Quiz ...

  - by lavanyadeepak

  A Good .NET Quiz ... Whilst casually surfing today afternoon I came across a good .NET quiz in one of the indian software company website. It is rather a general technology quiz than just a .NET quiz because it also contains options for the following technologies.   .NET PHP Javascript MySql Testing QTP English Aptitude General Knowledge Science HTML CSS All It also has the following levels for the Quiz:   Easy Medium Hard All   The URL of the quiz is as below: http://www.qualitypointtech.net/quiz/listing_sub_level.php

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• Grub2 -- Dualboot Ubuntu LTS 12.04 and Windows 7 -- Detects two Windows 7 (loader) entries

  - by DarkIron112

  this is the first question I have ever asked the Ubuntu Community. :D I'm fairly new to Ubuntu, but I understand the basics and know how to navigate the Terminal. I also know how to ask for/research my problems before asking for/ help. I have scoured the internet high and low and learned much of how Grub2 works. But nothing has helped me to solve my problem. My problem is this: I have a computer that has three hard drives. It previously had Windows XP, but I upgraded to Windows 7. I also installed Ubuntu 12.04 LTS (Precise Pangolin). During my installation of Windows 7, there was a failure and I had to restart the installation. Afterwards, I installed Ubuntu. After some trouble removing all traces of the XP OS (Ubuntu auto-detected it, but not Windows 7) I got the two OSes working flawlessly. Or, almost. When booting up, Grub2 used to display Ubuntu, Ubuntu Recovery Mode, Other Versions of Linux, memtest, followed by "Windows 7 (loader) on /dev/sda1" and "Windows 7 (loader) on /dev/sdb1". I eventually removed Recovery Mode, Other Versions, and Memtest. Now, when I run: sudo update-grub I get this print-out: Generating grub.cfg ... Found linux image: /boot/vmlinuz-3.2.0-26-generic Found initrd image: /boot/initrd.img-3.2.0-26-generic Found Windows 7 (loader) on /dev/sda1 Found Windows 7 (loader) on /dev/sdb1 I would like to remove "Windows 7 (loader) on /dev/sda1", as it is a broken entry that shouldn't exist, and must have been installed during my first Windows 7 attempt. I cannot find a Windows 7 entry in /etc/grub.d... And I don't know where to look. Here is a layout of my hard drives: /dev/sda1/ (1.82 TiB), NTFS ("Media") /dev/sdb1/ (100 Mib), NTFS ("System Reserved") /dev/sdb2/ (149 GiB), NTFS ("Windows 7") /dev/sdb3/ (149 GiB), Extended (" ") /dev/sdb4/ (145 GiB), ext4 (" ") /dev/sdb5/ (4 GiB), linux-swap (" ") /dev/sdc1/ (488.28 GiB), NTFS ("Downloads") /dev/sdc2/ (488.28 GiB), NTFS ("AltMedia") /dev/sdc3/ (886.45 GiB), NTFS ("Personal") unallocated (2.09 MiB), unallocated What I think has happened: Windows 7 installed first and badly. I installed it again. First, there was Windows XP to guide where the bootloader went to so it was put on /dev/sdb1/. But, the second time no such guide existed so the machine put another bootloader on /dev/sda1/. sda1, by the way, is the only partition on a 2TB drive. No boot record partition appears to exist according to gedit. I'm not sure where Grub2 is getting this information from. But, there it is. Is there anything somebody can do to help me? Or, is there any more information I should add? Thank you, community!

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• Much Ado About Nothing: Stub Objects

  - by user9154181

  The Solaris 11 link-editor (ld) contains support for a new type of object that we call a stub object. A stub object is a shared object, built entirely from mapfiles, that supplies the same linking interface as the real object, while containing no code or data. Stub objects cannot be executed — the runtime linker will kill any process that attempts to load one. However, you can link to a stub object as a dependency, allowing the stub to act as a proxy for the real version of the object. You may well wonder if there is a point to producing an object that contains nothing but linking interface. As it turns out, stub objects are very useful for building large bodies of code such as Solaris. In the last year, we've had considerable success in applying them to one of our oldest and thorniest build problems. In this discussion, I will describe how we came to invent these objects, and how we apply them to building Solaris. This posting explains where the idea for stub objects came from, and details our long and twisty journey from hallway idea to standard link-editor feature. I expect that these details are mainly of interest to those who work on Solaris and its makefiles, those who have done so in the past, and those who work with other similar bodies of code. A subsequent posting will omit the history and background details, and instead discuss how to build and use stub objects. If you are mainly interested in what stub objects are, and don't care about the underlying software war stories, I encourage you to skip ahead. The Long Road To Stubs This all started for me with an email discussion in May of 2008, regarding a change request that was filed in 2002, entitled: 4631488 lib/Makefile is too patient: .WAITs should be reduced This CR encapsulates a number of cronic issues with Solaris builds: We build Solaris with a parallel make (dmake) that tries to build as much of the code base in parallel as possible. There is a lot of code to build, and we've long made use of parallelized builds to get the job done quicker. This is even more important in today's world of massively multicore hardware. Solaris contains a large number of executables and shared objects. Executables depend on shared objects, and shared objects can depend on each other. Before you can build an object, you need to ensure that the objects it needs have been built. This implies a need for serialization, which is in direct opposition to the desire to build everying in parallel. To accurately build objects in the right order requires an accurate set of make rules defining the things that depend on each other. This sounds simple, but the reality is quite complex. In practice, having programmers explicitly specify these dependencies is a losing strategy: It's really hard to get right. It's really easy to get it wrong and never know it because things build anyway. Even if you get it right, it won't stay that way, because dependencies between objects can change over time, and make cannot help you detect such drifing. You won't know that you got it wrong until the builds break. That can be a long time after the change that triggered the breakage happened, making it hard to connect the cause and the effect. Usually this happens just before a release, when the pressure is on, its hard to think calmly, and there is no time for deep fixes. As a poor compromise, the libraries in core Solaris were built using a set of grossly incomplete hand written rules, supplemented with a number of dmake .WAIT directives used to group the libraries into sets of non-interacting groups that can be built in parallel because we think they don't depend on each other. From time to time, someone will suggest that we could analyze the built objects themselves to determine their dependencies and then generate make rules based on those relationships. This is possible, but but there are complications that limit the usefulness of that approach: To analyze an object, you have to build it first. This is a classic chicken and egg scenario. You could analyze the results of a previous build, but then you're not necessarily going to get accurate rules for the current code. It should be possible to build the code without having a built workspace available. The analysis will take time, and remember that we're constantly trying to make builds faster, not slower. By definition, such an approach will always be approximate, and therefore only incremantally more accurate than the hand written rules described above. The hand written rules are fast and cheap, while this idea is slow and complex, so we stayed with the hand written approach. Solaris was built that way, essentially forever, because these are genuinely difficult problems that had no easy answer. The makefiles were full of build races in which the right outcomes happened reliably for years until a new machine or a change in build server workload upset the accidental balance of things. After figuring out what had happened, you'd mutter "How did that ever work?", add another incomplete and soon to be inaccurate make dependency rule to the system, and move on. This was not a satisfying solution, as we tend to be perfectionists in the Solaris group, but we didn't have a better answer. It worked well enough, approximately. And so it went for years. We needed a different approach — a new idea to cut the Gordian Knot. In that discussion from May 2008, my fellow linker-alien Rod Evans had the initial spark that lead us to a game changing series of realizations: The link-editor is used to link objects together, but it only uses the ELF metadata in the object, consisting of symbol tables, ELF versioning sections, and similar data. Notably, it does not look at, or understand, the machine code that makes an object useful at runtime. If you had an object that only contained the ELF metadata for a dependency, but not the code or data, the link-editor would find it equally useful for linking, and would never know the difference. Call it a stub object. In the core Solaris OS, we require all objects to be built with a link-editor mapfile that describes all of its publically available functions and data. Could we build a stub object using the mapfile for the real object? It ought to be very fast to build stub objects, as there are no input objects to process. Unlike the real object, stub objects would not actually require any dependencies, and so, all of the stubs for the entire system could be built in parallel. When building the real objects, one could link against the stub objects instead of the real dependencies. This means that all the real objects can be built built in parallel too, without any serialization. We could replace a system that requires perfect makefile rules with a system that requires no ordering rules whatsoever. The results would be considerably more robust. We immediately realized that this idea had potential, but also that there were many details to sort out, lots of work to do, and that perhaps it wouldn't really pan out. As is often the case, it would be necessary to do the work and see how it turned out. Following that conversation, I set about trying to build a stub object. We determined that a faithful stub has to do the following: Present the same set of global symbols, with the same ELF versioning, as the real object. Functions are simple — it suffices to have a symbol of the right type, possibly, but not necessarily, referencing a null function in its text segment. Copy relocations make data more complicated to stub. The possibility of a copy relocation means that when you create a stub, the data symbols must have the actual size of the real data. Any error in this will go uncaught at link time, and will cause tragic failures at runtime that are very hard to diagnose. For reasons too obscure to go into here, involving tentative symbols, it is also important that the data reside in bss, or not, matching its placement in the real object. If the real object has more than one symbol pointing at the same data item, we call these aliased symbols. All data symbols in the stub object must exhibit the same aliasing as the real object. We imagined the stub library feature working as follows: A command line option to ld tells it to produce a stub rather than a real object. In this mode, only mapfiles are examined, and any object or shared libraries on the command line are are ignored. The extra information needed (function or data, size, and bss details) would be added to the mapfile. When building the real object instead of the stub, the extra information for building stubs would be validated against the resulting object to ensure that they match. In exploring these ideas, I immediately run headfirst into the reality of the original mapfile syntax, a subject that I would later write about as The Problem(s) With Solaris SVR4 Link-Editor Mapfiles. The idea of extending that poor language was a non-starter. Until a better mapfile syntax became available, which seemed unlikely in 2008, the solution could not involve extentions to the mapfile syntax. Instead, we cooked up the idea (hack) of augmenting mapfiles with stylized comments that would carry the necessary information. A typical definition might look like: # DATA(i386) __iob 0x3c0 # DATA(amd64,sparcv9) __iob 0xa00 # DATA(sparc) __iob 0x140 iob; A further problem then became clear: If we can't extend the mapfile syntax, then there's no good way to extend ld with an option to produce stub objects, and to validate them against the real objects. The idea of having ld read comments in a mapfile and parse them for content is an unacceptable hack. The entire point of comments is that they are strictly for the human reader, and explicitly ignored by the tool. Taking all of these speed bumps into account, I made a new plan: A perl script reads the mapfiles, generates some small C glue code to produce empty functions and data definitions, compiles and links the stub object from the generated glue code, and then deletes the generated glue code. Another perl script used after both objects have been built, to compare the real and stub objects, using data from elfdump, and validate that they present the same linking interface. By June 2008, I had written the above, and generated a stub object for libc. It was a useful prototype process to go through, and it allowed me to explore the ideas at a deep level. Ultimately though, the result was unsatisfactory as a basis for real product. There were so many issues: The use of stylized comments were fine for a prototype, but not close to professional enough for shipping product. The idea of having to document and support it was a large concern. The ideal solution for stub objects really does involve having the link-editor accept the same arguments used to build the real object, augmented with a single extra command line option. Any other solution, such as our prototype script, will require makefiles to be modified in deeper ways to support building stubs, and so, will raise barriers to converting existing code. A validation script that rederives what the linker knew when it built an object will always be at a disadvantage relative to the actual linker that did the work. A stub object should be identifyable as such. In the prototype, there was no tag or other metadata that would let you know that they weren't real objects. Being able to identify a stub object in this way means that the file command can tell you what it is, and that the runtime linker can refuse to try and run a program that loads one. At that point, we needed to apply this prototype to building Solaris. As you might imagine, the task of modifying all the makefiles in the core Solaris code base in order to do this is a massive task, and not something you'd enter into lightly. The quality of the prototype just wasn't good enough to justify that sort of time commitment, so I tabled the project, putting it on my list of long term things to think about, and moved on to other work. It would sit there for a couple of years. Semi-coincidentally, one of the projects I tacked after that was to create a new mapfile syntax for the Solaris link-editor. We had wanted to do something about the old mapfile syntax for many years. Others before me had done some paper designs, and a great deal of thought had already gone into the features it should, and should not have, but for various reasons things had never moved beyond the idea stage. When I joined Sun in late 2005, I got involved in reviewing those things and thinking about the problem. Now in 2008, fresh from relearning for the Nth time why the old mapfile syntax was a huge impediment to linker progress, it seemed like the right time to tackle the mapfile issue. Paving the way for proper stub object support was not the driving force behind that effort, but I certainly had them in mind as I moved forward. The new mapfile syntax, which we call version 2, integrated into Nevada build snv_135 in in February 2010: 6916788 ld version 2 mapfile syntax PSARC/2009/688 Human readable and extensible ld mapfile syntax In order to prove that the new mapfile syntax was adequate for general purpose use, I had also done an overhaul of the ON consolidation to convert all mapfiles to use the new syntax, and put checks in place that would ensure that no use of the old syntax would creep back in. That work went back into snv_144 in June 2010: 6916796 OSnet mapfiles should use version 2 link-editor syntax That was a big putback, modifying 517 files, adding 18 new files, and removing 110 old ones. I would have done this putback anyway, as the work was already done, and the benefits of human readable syntax are obvious. However, among the justifications listed in CR 6916796 was this We anticipate adding additional features to the new mapfile language that will be applicable to ON, and which will require all sharable object mapfiles to use the new syntax. I never explained what those additional features were, and no one asked. It was premature to say so, but this was a reference to stub objects. By that point, I had already put together a working prototype link-editor with the necessary support for stub objects. I was pleased to find that building stubs was indeed very fast. On my desktop system (Ultra 24), an amd64 stub for libc can can be built in a fraction of a second: % ptime ld -64 -z stub -o stubs/libc.so.1 -G -hlibc.so.1 \ -ztext -zdefs -Bdirect ... real 0.019708910 user 0.010101680 sys 0.008528431 In order to go from prototype to integrated link-editor feature, I knew that I would need to prove that stub objects were valuable. And to do that, I knew that I'd have to switch the Solaris ON consolidation to use stub objects and evaluate the outcome. And in order to do that experiment, ON would first need to be converted to version 2 mapfiles. Sub-mission accomplished. Normally when you design a new feature, you can devise reasonably small tests to show it works, and then deploy it incrementally, letting it prove its value as it goes. The entire point of stub objects however was to demonstrate that they could be successfully applied to an extremely large and complex code base, and specifically to solve the Solaris build issues detailed above. There was no way to finesse the matter — in order to move ahead, I would have to successfully use stub objects to build the entire ON consolidation and demonstrate their value. In software, the need to boil the ocean can often be a warning sign that things are trending in the wrong direction. Conversely, sometimes progress demands that you build something large and new all at once. A big win, or a big loss — sometimes all you can do is try it and see what happens. And so, I spent some time staring at ON makefiles trying to get a handle on how things work, and how they'd have to change. It's a big and messy world, full of complex interactions, unspecified dependencies, special cases, and knowledge of arcane makefile features... ...and so, I backed away, put it down for a few months and did other work... ...until the fall, when I felt like it was time to stop thinking and pondering (some would say stalling) and get on with it. Without stubs, the following gives a simplified high level view of how Solaris is built: An initially empty directory known as the proto, and referenced via the ROOT makefile macro is established to receive the files that make up the Solaris distribution. A top level setup rule creates the proto area, and performs operations needed to initialize the workspace so that the main build operations can be launched, such as copying needed header files into the proto area. Parallel builds are launched to build the kernel (usr/src/uts), libraries (usr/src/lib), and commands. The install makefile target builds each item and delivers a copy to the proto area. All libraries and executables link against the objects previously installed in the proto, implying the need to synchronize the order in which things are built. Subsequent passes run lint, and do packaging. Given this structure, the additions to use stub objects are: A new second proto area is established, known as the stub proto and referenced via the STUBROOT makefile macro. The stub proto has the same structure as the real proto, but is used to hold stub objects. All files in the real proto are delivered as part of the Solaris product. In contrast, the stub proto is used to build the product, and then thrown away. A new target is added to library Makefiles called stub. This rule builds the stub objects. The ld command is designed so that you can build a stub object using the same ld command line you'd use to build the real object, with the addition of a single -z stub option. This means that the makefile rules for building the stub objects are very similar to those used to build the real objects, and many existing makefile definitions can be shared between them. A new target is added to the Makefiles called stubinstall which delivers the stub objects built by the stub rule into the stub proto. These rules reuse much of existing plumbing used by the existing install rule. The setup rule runs stubinstall over the entire lib subtree as part of its initialization. All libraries and executables link against the objects in the stub proto rather than the main proto, and can therefore be built in parallel without any synchronization. There was no small way to try this that would yield meaningful results. I would have to take a leap of faith and edit approximately 1850 makefiles and 300 mapfiles first, trusting that it would all work out. Once the editing was done, I'd type make and see what happened. This took about 6 weeks to do, and there were many dark days when I'd question the entire project, or struggle to understand some of the many twisted and complex situations I'd uncover in the makefiles. I even found a couple of new issues that required changes to the new stub object related code I'd added to ld. With a substantial amount of encouragement and help from some key people in the Solaris group, I eventually got the editing done and stub objects for the entire workspace built. I found that my desktop system could build all the stub objects in the workspace in roughly a minute. This was great news, as it meant that use of the feature is effectively free — no one was likely to notice or care about the cost of building them. After another week of typing make, fixing whatever failed, and doing it again, I succeeded in getting a complete build! The next step was to remove all of the make rules and .WAIT statements dedicated to controlling the order in which libraries under usr/src/lib are built. This came together pretty quickly, and after a few more speed bumps, I had a workspace that built cleanly and looked like something you might actually be able to integrate someday. This was a significant milestone, but there was still much left to do. I turned to doing full nightly builds. Every type of build (open, closed, OpenSolaris, export, domestic) had to be tried. Each type failed in a new and unique way, requiring some thinking and rework. As things came together, I became aware of things that could have been done better, simpler, or cleaner, and those things also required some rethinking, the seeking of wisdom from others, and some rework. After another couple of weeks, it was in close to final form. My focus turned towards the end game and integration. This was a huge workspace, and needed to go back soon, before changes in the gate would made merging increasingly difficult. At this point, I knew that the stub objects had greatly simplified the makefile logic and uncovered a number of race conditions, some of which had been there for years. I assumed that the builds were faster too, so I did some builds intended to quantify the speedup in build time that resulted from this approach. It had never occurred to me that there might not be one. And so, I was very surprised to find that the wall clock build times for a stock ON workspace were essentially identical to the times for my stub library enabled version! This is why it is important to always measure, and not just to assume. One can tell from first principles, based on all those removed dependency rules in the library makefile, that the stub object version of ON gives dmake considerably more opportunities to overlap library construction. Some hypothesis were proposed, and shot down: Could we have disabled dmakes parallel feature? No, a quick check showed things being build in parallel. It was suggested that we might be I/O bound, and so, the threads would be mostly idle. That's a plausible explanation, but system stats didn't really support it. Plus, the timing between the stub and non-stub cases were just too suspiciously identical. Are our machines already handling as much parallelism as they are capable of, and unable to exploit these additional opportunities? Once again, we didn't see the evidence to back this up. Eventually, a more plausible and obvious reason emerged: We build the libraries and commands (usr/src/lib, usr/src/cmd) in parallel with the kernel (usr/src/uts). The kernel is the long leg in that race, and so, wall clock measurements of build time are essentially showing how long it takes to build uts. Although it would have been nice to post a huge speedup immediately, we can take solace in knowing that stub objects simplify the makefiles and reduce the possibility of race conditions. The next step in reducing build time should be to find ways to reduce or overlap the uts part of the builds. When that leg of the build becomes shorter, then the increased parallelism in the libs and commands will pay additional dividends. Until then, we'll just have to settle for simpler and more robust. And so, I integrated the link-editor support for creating stub objects into snv_153 (November 2010) with 6993877 ld should produce stub objects PSARC/2010/397 ELF Stub Objects followed by the work to convert the ON consolidation in snv_161 (February 2011) with 7009826 OSnet should use stub objects 4631488 lib/Makefile is too patient: .WAITs should be reduced This was a huge putback, with 2108 modified files, 8 new files, and 2 removed files. Due to the size, I was allowed a window after snv_160 closed in which to do the putback. It went pretty smoothly for something this big, a few more preexisting race conditions would be discovered and addressed over the next few weeks, and things have been quiet since then. Conclusions and Looking Forward Solaris has been built with stub objects since February. The fact that developers no longer specify the order in which libraries are built has been a big success, and we've eliminated an entire class of build error. That's not to say that there are no build races left in the ON makefiles, but we've taken a substantial bite out of the problem while generally simplifying and improving things. The introduction of a stub proto area has also opened some interesting new possibilities for other build improvements. As this article has become quite long, and as those uses do not involve stub objects, I will defer that discussion to a future article.

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• The winning combination: Oracle VM Server for x86 + Oracle Sun Fire HW

  - by Karim Berrah

  You might be wondering why OVM Server for x86 (OVM/x86 here and below) should be seriously considered as a nice (business point of view) alternative to standard Hypervisors, if you are virtualizing Oracle Software, especially if you are planning to move to Oracle x86 Hardware (rackmount or blades). Well, let see some "not well known" facts that might interest you and help you in saving more money for your entire company (and not only the Virtulization team). Fact 1: OVM/x86 is considered as a hard partitionning technology (check page 2 of Oracle Server Partitionning Licencing Policies), so if you are buying new servers based on the latest INTEL Xeon E7 CPUs (10 cores per Socket) and have some licencing issues in deploying further Oracle SW, because you are using a hypervisor not recognized as a hard partitionning technology (like VMware), then you need to check here how to do it with OVM . This might help you to continue to deploy your Oracle DB instances on new x86 HW (12 cores, 40 cores, 64 cores servers) in a reasonable way, without having to pay licences for 12 CPU, 40 CPUs or 64 CPUs. You might also consider migrating your legacy Oracle DB DBs to a virtualized environment like OVM/x86 an recover some CPU licences, that can be reused somewhere else in production. Fact 2: OVM/x86 is free to use, without any extra licence for any specific feature (LiveMigration, High Availability, Embedded Management Console). If you want to use it on non Oracle HW, there is a support fee per  system and per year, that is much below VMware support (Oracle VM Premier Limited Support for systems up to 2 CPUs, and Oracle VM Premier Support for any bigger system, independently on the number of populated sockets). Fact 3: support is included with your Oracle x86 HW support (OPS for systems)  and you can re-install on you system Oracle Linux, Oracle Solaris or Oracle VM server for x86, without beeing charged, an keeping the same support level. Fact 4: it is less expensive to virtualize Oracle Linux or Oracle Solaris on OVM/x86 with Oracle HW that any other similar solution with VMware, because all the VMs are then supported and licenced when you buy Oracle HW with OPS. Fact 5: Oracle VM Templates bring you many Virtual Machines already installed, patched and optimized for various Oracle applications. And to be more specific, those templates are fully supported by Oracle, which is not really true when it comes to another hypervisor. By optimized VM Kernel, I mean PV drivers, OVM-ready kernels in the VM, single source clock for all the VMS, better memory management of the VM ... Fact 6: there is no extra costs for a management console. OVM comes with a free OVM Manager package for Linux.  More infos: Latest announcement of OVM/x86 update 2.2.2 A short flash demo of OVM server for x86 A short flash demo on OVM Templates and Virtual Assembly Builder Oracle Linux Support and Oracle VM Support Global Price List  ISVs: Benefits for Independant Sofwtare Vendors (ISVs) in using OVM/x86 Consultant Services: Advanced Customer Services for OVM/x86  Technical Features Best practices and Guideline for OVM with Oracle Blades Reduce TCO and get more Value from your x86 Infrastructure

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