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  • Printer Naming Conventions

    - by John
    I am working on building a new AD print server and have been pondering the idea of renaming the printers. Right now we have a mix of names that varies between a mashup of some that reference location, some that reference functional area, and some that are rather generic. Some examples include the following: Dell 5210 - Building Name HP 4350 - Functional Area Dell Color 3100 - Location and Building Number HP 6500 - Mailroom I was curious what other people used to name their printers with. What conventions do you use and how to design a method that will be able to be used for a while without needing to rename them all again. Also, the naming methodology needs to be understandable for regular computing users so that they can relatively easily find the printer that they need. I was looking at some ideas from here, but I was not sure how practical some of them are. Any help that you can provide is appreciated. Note: I have reviewed many of the postings on here in relation to server naming conventions and found that they were not specific enough for the use case I present above.

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  • KVM Hosting: How to efficiently replicate guests

    - by javano
    I have three KVM servers each with 1 guest VM, running directly on it's local storage, (so they are essentially getting a dedicated box worth of computing power each). In the event of a host failure I would like the guests replicated to at least one of the other hosts so I can spin it up there, until the failing host is fixed. I am curious about KVM cloning. I can clone a VM live or when it's suspended/shutdown. Obivously suspended VMs will naturally be quicker to clone but these three VMs comprise three parts of a single solution, so I don't want to ever have any one of them shutdown. How can I efficiently clone these VMs between servers? I have had a couple of ideas, but are these insane or, is there a better method I have missed for my scenario? Set up a DRDB partition between box 1 and 2 where VM 1 runs from, and so is replicated between box1 and box 2, repeat between box 2 & 3, and box 3 & 1 (This could be insane, I have never used DRDB only read about it) Just use standard KVM CLI clone options to perform live clones (I'm dubious about this because I don't know how long it will take and what the performance impact will be during) Run a copy of each VM on at least one other host, and have the guest on one host export it's data to the matching guest on another host where it can import that data, scripting this on the guest) Some of other way? Ideas welcome! Side Note These servers have 4x15k SAS drives in a RAID 10 so they aren't rocketing fast, and as I mentioned, each VM runs from the host's local storage, no NAS or SAN etc. So that is why I am asking this question about guest replication. Also, this isn't about disaster recovery. Guests will be exporting their data to a NAS over a VPN, so I am looking at how I can have them quickly spun up in a host failure situation.

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  • Provider claiming "all web servers in the cloud are automatically kept in sync" - should I be skeptical?

    - by RobMasters
    I'm no expert in cloud computing - I've spent a fair bit of time researching it and various providers but am yet to get any hands-on experience with it. From what I've read about AWS and auto-scaling EC2 instances though, it seems as though each instance should be completely decoupled from all other instances. i.e. If content is uploaded to the web server's local filesystem from a custom CMS backend then that content won't be available if subsequently requested from a different web server in the auto-scaling group. Is that right? I met with a representative of our existing hosting provider recently and he was claiming that it isn't a problem that our legacy CMS system is highly dependent on having a local filesystem. He said that all web servers, regardless of how many, would be kept as exact duplicates so I shouldn't notice any difference compared to our existing setup of a single dedicated server. This smells a little too much like bull fecal-matter to me...should I be skeptical about this? I'm a little worried because my (non-technical) boss who ultimately makes the decisions is all for signing up to this cloud solution because it won't require any extra work. I'm sure that they must at least be able to provide this, otherwise they wouldn't be attempting to sell it to us. But at what cost? It sounds as though each web server will always need to be checking the other web server(s) for new static content, which to me sounds like unwanted overhead that'll slow things down. I'd really appreciate it if somebody could clear this up to me. I'm all for switching to AWS and using S3+CloudFront for all static content, but that isn't looking very likely to happen at the moment.

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  • Diagnosing RAM issues

    - by TaylorND
    I have an old Acer Aspire T180 desktop. The specs are as follows: AMD Athlon 64 3800+ 2.4GHz 1GB DDR2 SDRAM 160GB DVD-Writer (DVD±R/±RW) Gigabit Ethernet 17" Active Matrix TFT Color LCD Windows Vista Home Basic Mini-tower AST180-UA381B According to the information in the computer's documentation the computer comes with 1 GB of RAM. It has two DDR2 SDRAM sticks. I used to have Windows Vista installed. Then I removed it and install Windows 7, and now I have since removed Windows 7 and installed Windows XP. According to Windows XP with both RAM sticks in the computer has 768 MB. Isn't this supposed to be 1 GB of RAM or 1024 MB of RAM? Is the amount of RAM installed only partly used by the Operating System? Is there's something I'm missing? If I remove either one of the RAM sticks I'm left with 448 MB of RAM. These numbers don't seem to add up. If each of the RAM sticks contains at least 448 MB of RAM shouldn't they (both being in) provide 896 MB of RAM. Even then, isn't that less than a GB of RAM? I'm not too experienced in hardware so I thought this would be the best place to ask. As a follow up question, is the RAM I have enough to run/multitask with Windows XP efficiently? I plan to do a lot of computing with the system (although not gaming), should I invest in more RAM?

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  • PXELinux and compressed kernels/images

    - by Yvan JANSSENS
    Is it possible to boot compressed kernels with a compressed initrd with PXELinux? First, a little background: We created a custom Linux distro, for diskless OpenCL computing nodes. We want those nodes to fetch their OS from the network. Our Distro is composed out of a kernel (duh) and a large initrd which is loaded into RAM and everything is executed from there. We chose to run everything off the initrd for two reasons: NFS was not an option to serve the filesystem's extra contents Fast file access from RAM. No persistent storage needed, data and config is pulled dynamically through a SOAP service. Now our initrd is about 450M in size. At our network speeds, it takes about two to three minutes to load a single client. Will compression speed up te downloading, and if yes, which one should be used? Is LZMA supported by PXELinux, or do we need to stick to bzip2 or gzip? Because of the 2-3 minutes loading time, booting 15 nodes over the same network link takes quite a lot of time. We decided not to use hard drives or CD/DVD drives, for financial reasons (cheapest HDD @ €30 times 15 is a lot of money saved ;-) ) So, our question is: what compression options are available for this setup? And how do we do this? Thank you for your time! Yvan Janssens

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  • What is the fall off of subsecond throughput on Ethernet Network Interfaces

    - by Kyle Brandt
    On a network interface, speeds are given in term of data over time, in particular, they are bits per second. However, in the uber-fast world of computing -- a second is kind of a really long time. So for example, given a linear falloff. A 1 GBit per second interface would do 500MBit per half second, 250Mbit per quarter second etc. I imagine at certain units of time, this is no longer linear. Perhaps this is set by ethernet frequencies, system clock speeds, interrupt timers etc. I am sure this varies depending on the system -- but does anyone have more information or whitepapers on this? One of the main reasons I am curious is to understand output drops on interfaces. Even if the speed per second is much lower than the interface can handle -- perhaps there are spikes that cause drops for only small numbers of milliseconds. Perhaps various coalescing would hide this effect -- or perhaps increase it on the receiving interface? Do queues make a difference here? Example: So given if this is linear down to the MS we would have 1Mbit/MS, and if Wireshark isn't distorting what I see, should I see drops when I have a spike beyond 1Mbit?

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  • Mixing both local and nonlocal addresses on three switches

    - by klew
    I have four computers that have nonlocal addresses like 150.X.X.X. Now I also get another few computers that should be only accessible through a gateway (it will be computing cluster) and they addresses are 10.0.0.X. I also wanted to include those four older computers to this new cluster, but I want them to be accessible from internet on nonlocal addresses (so I would like to set up them on both 150.X.X.X and 10.0.0.X addresses - I've set up it as interface eth0:0 since I have only one NIC). Those new computers have their switch and old computers also have their own switch. Both of them are connected to another (third) switch. The problem is that those old computers see each other (I can ping them), and also new computers see each other, but I can't ping old computer from new computer and vice versa. However pinging on nonlocal adresses works as expected. I looked into switch configuration and didn't find anything useful. I have no idea what I missed here. Can somebody help? All computers have Ubuntu Server 10.04

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  • Am I safe on Windows if I continue like this?

    - by max
    Of all the available tons of anti-malware software for Windows all over the internet, I've never used any paid solution(I am a student, I have no money). Since the last 10 years, my computers running Windows have never been hacked/compromised or infected so badly that I had to reformat them(of course I did reformat them for other reasons). The only program I have for security is Avast Home Edition, which is free, installed on my computers. It has never caused any problems; always detected malware, updated automatically, has an option to sandbox programs and everything else I need. Even if I got infected, I just did a boot-time scan with it, downloaded and ran Malwarebytes, scanned Autoruns logs, checked running processes with Process Explorer and did some other things and made sure I cleaned my computer. I am quite experienced and I've always taken basic precautions like not clicking suspicious executables, not going to sites which are suspicious according to WOT, and all that blah. But recently I've been doing more and more online transactions and since its 2012 now, I'm doubtful whether I need more security or not. Have I been just lucky, or do my computing habits obviate the need to use any more(or paid) security software?

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  • thought about shared storage (NFS, Lustre) [closed]

    - by user134880
    Possible Duplicate: Can you help me with my capacity planning? Now I habe small cluster with total of 8 nodes. 6 of them are computing nodes (apache and vmware) and 2 nodes are for storage. 2 storage nodes are identical. Each storage server is linux box with 8 x 1Tb WD RE4 in soft raid 10. 1st box is master and 2nd is slave. Data is mirrored with DRDB. We export NFSv4 shares to Apache (for document root) and iSCSI to Vmware. Now all is working pretty good and stable. But it will be soon time to upgrade our system. I have been thinking of Lustre. Does some one has any real experience with Lustre or NFS medium clusters? Will it be good idea just to upgrade server and change hdd's to 3Tb ? With NFS we will always have only 2 servers to maintain (one primary and one slave). Thanks. QUESTIONS: 1) Does some one used Lustre? In production? I have seen a lot of info about how it is hard to setup Lustre because you need to compile own kernel and patches. It's answers from newbies. Is there some one who has used Lustre for some period of time? 2) About disk upgrades - it's only description of strategy. I'm not asking if it is enough 3Tb or not. I just ask if it is right just to replace hdds instead of adding new server (like with Lustre) Thanks again.

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  • Nvidia 9800GT randomly prevents computer from booting

    - by Blender
    My computer has been running Windows and Linux perfectly fine with my 9800GT for the past year or so, but today it refused to boot. When I press the power button, this is what happens: Power button flashes once. Fans whir. Graphics card makes clicking noise. Computer reboots. Go back to 1. The cycle just keeps going, and I have to yank the cord to make the computer stop. After about 30 attempts at booting it, the computer powers on and everything works. I'm pretty sure that the graphics card isn't malfunctioning, as I've been GPU computing on it for a while now without any hiccups. But the strange thing is, the computer boots perfectly fine in only 5 boots if I remove the card. The computer is a HP Pavilion a6028x Desktop PC: Processor: AMD Athlon 64 X2 (W) 4600+ 2.4 GHz (AM2 socket) Motherboard: ECS MCP61PM-HM (Nettle 1) RAM: 3GB DDR2 (two different brands) More specs here Does anybody know what could be the problem? Any help or information would be greatly appreciated!

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  • Network using only switches

    - by mschultz
    So I'm not a network guy - but here's what I want to do - I have an existing network using wifi, which I like, and which is used to connect several computers to the internet. It is headed up by a router, which is in another part of the building. Three of those computers are in my office. All three have gigabit wired ethernet. I have a gigabit switch. Here's what I want to do: Build a 2nd network, out of just that switch, which allows all 3 computers to connect to each other (just to each other is fine, for this purpose, they need no internet). I have a distributed computing task (rendering high-quality fractal artwork, as it were), that requires the best connection speed to all 3 computers. I want them to be able to "talk to each other" as quickly as possible, with the fewest dropped packets (the dataflow over this network will be quite high). So how do I do this. I'm not a networking guy at all - I tried connecting them all, and nobody got an IP address (which I assume is because nobody is running a DNS server?). What all do I need to do to make this work? PS - two are running windows, one is running ubuntu.

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  • 26 Days: Countdown to Oracle OpenWorld 2012

    - by Michael Snow
    Welcome to our countdown to Oracle OpenWorld! Oracle OpenWorld 2012 is just around the corner. In less than 26 days, San Francisco will be invaded by an expected 50,000 people from all over the world. Here on the Oracle WebCenter team, we’ve all been working to help make the experience a great one for all our WebCenter customers. For a sneak peak  – we’ll be spending this week giving you a teaser of what to look forward to if you are joining us in San Francisco from September 30th through October 4th. We have Oracle WebCenter sessions covering all topics imaginable. Take a look and use the tools we provide to build out your schedule in advance and reserve your seats in your favorite sessions.  That gives you plenty of time to plan for your week with us in San Francisco. If unfortunately, your boss denied your request to attend - there are still some ways that you can join in the experience virtually On-Demand. This year - we are expanding even more up North of Market Street and will be taking over Union Square as well. Check out this map of San Francisco to get a sense of how much of a footprint Oracle OpenWorld has grown to this year. With so much to see and so many sessions to learn from - its no wonder that people get excited. Add to that a good mix of fun and all of the possible WebCenter sessions you could attend - you won't want to sleep at all to take full advantage of such an opportunity. We'll also have our annual WebCenter Customer Appreciation reception - stay tuned this week for some more info on registration to make sure you'll be able to join us. If you've been following the America's Cup at all and believe in EXTREME PERFORMANCE you'll definitely want to take a look at this video from last year's OpenWorld Keynote. 12.00 Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-family:"Calibri","sans-serif"; mso-ascii- mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi- mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} Important OpenWorld Links:  Attendee / Presenters Toolkit Oracle Schedule Builder WebCenter Sessions (listed in the catalog under Fusion Middleware as "Portals, Sites, Content, and Collaboration" ) Oracle Music Festival - AMAZING Line up!!  Oracle Customer Appreciation Night -LOOK HERE!! Oracle OpenWorld LIVE On-Demand Here are all the WebCenter sessions broken down by day for your viewing pleasure. Monday, October 1st CON8885 - Simplify CRM Engagement with Contextual Collaboration Are your sales teams disconnected and disengaged? Do you want a tool for easily connecting expertise across your organization and providing visibility into the complete sales process? Do you want a way to enhance and retain organization knowledge? Oracle Social Network is the answer. Attend this session to learn how to make CRM easy, effective, and efficient for use across virtual sales teams. Also learn how Oracle Social Network can drive sales force collaboration with natural conversations throughout the sales cycle, promote sales team productivity through purposeful social networking without the noise, and build cross-team knowledge by integrating conversations with CRM and other business applications. CON8268 - Oracle WebCenter Strategy: Engaging Your Customers. Empowering Your Business Oracle WebCenter is a user engagement platform for social business, connecting people and information. Attend this session to learn about the Oracle WebCenter strategy, and understand where Oracle is taking the platform to help companies engage customers, empower employees, and enable partners. Business success starts with ensuring that everyone is engaged with the right people and the right information and can access what they need through the channel of their choice—Web, mobile, or social. Are you giving customers, employees, and partners the best-possible experience? Come learn how you can! ¶ HOL10208 - Add Social Capabilities to Your Enterprise Applications Oracle Social Network enables you to add real-time collaboration capabilities into your enterprise applications, so that conversations can happen directly within your business systems. In this hands-on lab, you will try out the Oracle Social Network product to collaborate with other attendees, using real-time conversations with document sharing capabilities. Next you will embed social capabilities into a sample Web-based enterprise application, using embedded UI components. Experts will also write simple REST-based integrations, using the Oracle Social Network API to programmatically create social interactions. ¶ CON8893 - Improve Employee Productivity with Intuitive and Social Work Environments Social technologies have already transformed the ways customers, employees, partners, and suppliers communicate and stay informed. Forward-thinking organizations today need technologies and infrastructures to help them advance to the next level and integrate social activities with business applications to deliver a user experience that simplifies business processes and enterprise application engagement. Attend this session to hear from an innovative Oracle Social Network customer and learn how you can improve productivity with intuitive and social work environments and empower your employees with innovative social tools to enable contextual access to content and dynamic personalization of solutions. ¶ CON8270 - Oracle WebCenter Content Strategy and Vision Oracle WebCenter provides a strategic content infrastructure for managing documents, images, e-mails, and rich media files. With a single repository, organizations can address any content use case, such as accounts payable, HR onboarding, document management, compliance, records management, digital asset management, or Website management. In this session, learn about future plans for how Oracle WebCenter will address new use cases as well as new integrations with Oracle Fusion Middleware and Oracle Applications, leveraging your investments by making your users more productive and error-free. ¶ CON8269 - Oracle WebCenter Sites Strategy and Vision Oracle’s Web experience management solution, Oracle WebCenter Sites, enables organizations to use the online channel to drive customer acquisition and brand loyalty. It helps marketers and business users easily create and manage contextually relevant, social, interactive online experiences across multiple channels on a global scale. In this session, learn about future plans for how Oracle WebCenter Sites will provide you with the tools, capabilities, and integrations you need in order to continue to address your customers’ evolving requirements for engaging online experiences and keep moving your business forward. ¶ CON8896 - Living with SharePoint SharePoint is a popular platform, but it’s not always the best fit for Oracle customers. In this session, you’ll discover the technical and nontechnical limitations and pitfalls of SharePoint and learn about Oracle alternatives for collaboration, portals, enterprise and Web content management, social computing, and application integration. The presentation shows you how to integrate with SharePoint when business or IT requirements dictate and covers cloud-based (Office 365) and on-premises versions of SharePoint. Presented by a former Microsoft director of SharePoint product management and backed by independent customer research, this session will prepare you to answer the question “Why don’t we just use SharePoint for that?’ the next time it comes up in your organization. ¶ CON7843 - Content-Enabling Enterprise Processes with Oracle WebCenter Organizations today continually strive to automate business processes, reduce costs, and improve efficiency. Many business processes are content-intensive and unstructured, requiring ad hoc collaboration, and distributed in nature, requiring many approvals and generating huge volumes of paper. In this session, learn how Oracle and SYSTIME have partnered to help a customer content-enable its enterprise with Oracle WebCenter Content and Oracle WebCenter Imaging 11g and integrate them with Oracle Applications. ¶ CON6114 - Tape Robotics’ Newest Superhero: Now Fueled by Oracle Software For small, midsize, and rapidly growing businesses that want the most energy-efficient, scalable storage infrastructure to meet their rapidly growing data demands, Oracle’s most recent addition to its award-winning tape portfolio leverages several pieces of Oracle software. With Oracle Linux, Oracle WebLogic, and Oracle Fusion Middleware tools, the library achieves a higher level of usability than previous products while offering customers a familiar interface for management, plus ease of use. This session examines the competitive advantages of the tape library and how Oracle software raises customer satisfaction. Learn how the combination of Oracle engineered systems, Oracle Secure Backup, and Oracle’s StorageTek tape libraries provide end-to-end coverage of your data. ¶ CON9437 - Mobile Access Management With more than five billion mobile devices on the planet and an increasing number of users using their own devices to access corporate data and applications, securely extending identity management to mobile devices has become a hot topic. This session focuses on how to extend your existing identity management infrastructure and policies to securely and seamlessly enable mobile user access. CON7815 - Customer Experience Online in Cloud: Oracle WebCenter Sites, Oracle ATG Apps, Oracle Exalogic Oracle WebCenter Sites and Oracle’s ATG product line together can provide a compelling marketing and e-commerce experience. When you couple them with the extreme performance of Oracle Exalogic, you’ll see unmatched scalability that provides you with a true cloud-based solution. In this session, you’ll learn how running Oracle WebCenter Sites and ATG applications on Oracle Exalogic delivers both a private and a public cloud experience. Find out what it takes to get these systems working together and delivering engaging Web experiences. Even if you aren’t considering Oracle Exalogic today, the rich Web experience of Oracle WebCenter, paired with the depth of the ATG product line, can provide your business full support, from merchandising through sale completion. ¶ CON8271 - Oracle WebCenter Portal Strategy and Vision To innovate and keep a competitive edge, organizations need to leverage the power of agile and responsive Web applications. Oracle WebCenter Portal enables you to do just that, by delivering intuitive user experiences for enterprise applications to drive innovation with composite applications and mashups. Attend this session to learn firsthand from customers how Oracle WebCenter Portal extends the value of existing enterprise applications, business processes, and content; delivers a superior business user experience; and maximizes limited IT resources. ¶ CON8880 - The Connected Customer Experience Begins with the Online Channel There’s a lot of talk these days about how to connect the customer journey across various touchpoints—from Websites and e-commerce to call centers and in-store—to provide experiences that are more relevant and engaging and ultimately gain competitive edge. Doing it all at once isn’t a realistic objective, so where do you start? Come to this session, and hear about three steps you can take that can help you begin your journey toward delivering the connected customer experience. You’ll hear how Oracle now has an integrated digital marketing platform for your corporate Website, your e-commerce site, your self-service portal, and your marketing and loyalty campaigns, and you’ll learn what you can do today to begin executing on your customer experience initiatives. ¶ GEN11451 - General Session: Building Mobile Applications with Oracle Cloud With the prevalence of smart mobile devices, companies are facing an increased demand to provide access to data and applications from new channels. However, developing applications for mobile devices poses some unique challenges. Come to this session to learn how Oracle addresses these challenges, offering a simpler way to develop and deploy cross-device mobile applications. See how Oracle Cloud enables you to access applications, data, and services from mobile channels in an easier way.  CON8272 - Oracle Social Network Strategy and Vision One key way of increasing employee productivity is by bringing people, processes, and information together—providing new social capabilities to enable business users to quickly correspond and collaborate on business activities. Oracle WebCenter provides a user engagement platform with social and collaborative technologies to empower business users to focus on their key business processes, applications, and content in the context of their role and process. Attend this session to hear how the latest social capabilities in Oracle Social Network are enabling organizations to transform themselves into social businesses.  --- Tuesday, October 2nd HOL10194 - Enterprise Content Management Simplified: Oracle WebCenter Content’s Next-Generation UI Regardless of the nature of your business, unstructured content underpins many of its daily functions. Whether you are working with traditional presentations, spreadsheets, or text documents—or even with digital assets such as images and multimedia files—your content needs to be accessible and manageable in convenient and intuitive ways to make working with the content easier. Additionally, you need the ability to easily share documents with coworkers to facilitate a collaborative working environment. Come to this session to see how Oracle WebCenter Content’s next-generation user interface helps modern knowledge workers easily manage personal and enterprise documents in a collaborative environment.¶ CON8877 - Develop a Mobile Strategy with Oracle WebCenter: Engage Customers, Employees, and Partners Mobile technology has gone from nice-to-have to a cornerstone of user engagement. Mobile access enables users to have information available at their fingertips, enabling them to take action the moment they make a decision, interact in the moment of convenience, and take advantage of new service offerings in their preferred channels. All your employees have your mobile applications in their pocket; now what are you going to do? It is a critical step for companies to think through what their employees, customers, and partners really need on their devices. Attend this session to see how Oracle WebCenter enables you to better engage your customers, employees, and partners by providing a unified experience across multiple channels. ¶ CON9447 - Enabling Access for Hundreds of Millions of Users How do you grow your business by identifying, authenticating, authorizing, and federating users on the Web, leveraging social identity and the open source OAuth protocol? How do you scale your access management solution to support hundreds of millions of users? With social identity support out of the box, Oracle’s access management solution is also benchmarked for 250-million-user deployment according to real-world customer scenarios. In this session, you will learn about the social identity capability and the 250-million-user benchmark testing of Oracle Access Manager and Oracle Adaptive Access Manager running on Oracle Exalogic and Oracle Exadata. ¶ HOL10207 - Build an Intranet Portal with Oracle WebCenter In this hands-on lab, you’ll work with Oracle WebCenter Portal and Oracle WebCenter Content to build out an enterprise portal that maximizes the productivity of teams and individual contributors. Using browser-based tools, you’ll manage site resources such as page styles, templates, and navigation. You’ll edit content stored in Oracle WebCenter Content directly from your portal. You’ll also experience the latest features that promote collaboration, social networking, and personal productivity. ¶ CON2906 - Get Proactive: Best Practices for Maintaining Oracle Fusion Middleware You chose Oracle Fusion Middleware products to help your organization deliver superior business results. Now learn how to take full advantage of your software with all the great tools, resources, and product updates you’re entitled to through Oracle Support. In this session, Oracle product experts provide proven best practices to help you work more efficiently, plan and prepare for upgrades and patching more effectively, and manage risk. Topics include configuration management tools, remote diagnostics, My Oracle Support Community, and My Oracle Support Lifecycle Advisors. New users and Oracle Fusion Middleware experts alike are guaranteed to leave with fresh ideas and practical, easy-to-implement next steps. ¶ CON8878 - Oracle WebCenter’s Cloud Strategy: From Social and Platform Services to Mashups Cloud computing represents a paradigm shift in how we build applications, automate processes, collaborate, and share and in how we secure our enterprise. Additionally, as you adopt cloud-based services in your organization, it’s likely that you will still have many critical on-premises applications running. With these mixed environments, multiple user interfaces, different security, and multiple datasources and content sources, how do you start evolving your strategy to account for these challenges? Oracle WebCenter offers a complete array of technologies enabling you to solve these challenges and prepare you for the cloud. Attend this session to learn how you can use Oracle WebCenter in the cloud as well as create on-premises and cloud application mash-ups. ¶ CON8901 - Optimize Enterprise Business Processes with Oracle WebCenter and Oracle BPM Do you have business processes that span multiple applications? Are you grappling with how to have visibility across these business processes; how to manage content that is associated with these processes; and, most importantly, how to model and optimize these business processes? Attend this session to hear how Oracle WebCenter and Oracle Business Process Management provide a unique set of integrated solutions to provide a composite application dashboard across these business processes and offer a solution for content-centric business processes. ¶ CON8883 - Deliver Engaging Interfaces to Oracle Applications with Oracle WebCenter Critical business processes live within enterprise applications, and application users need to manage and execute these processes as effectively as possible. Oracle provides a comprehensive user engagement platform to increase user productivity and optimize overall processes within Oracle Applications—Oracle E-Business Suite and Oracle’s Siebel, PeopleSoft, and JD Edwards product families—and third-party applications. Attend this session to learn how you can integrate these applications with Oracle WebCenter to deliver composite application dashboards to your end users—whether they are your customers, partners, or employees—for enhanced usability and Web 2.0–enabled enterprise portals.¶ Wednesday, October 3rd CON8895 - Future-Ready Intranets: How Aramark Re-engineered the Application Landscape There are essential techniques and technologies you can use to deliver employee portals that garner higher productivity, improve business efficiency, and increase user engagement. Attend this session to learn how you can leverage Oracle WebCenter Portal as a user engagement platform for bringing together business process management, enterprise content management, and business intelligence into a highly relevant and integrated experience. Hear how Aramark has leveraged Oracle WebCenter Portal and Oracle WebCenter Content to deliver a unified workspace providing simpler navigation and processing, consolidation of tools, easy access to information, integrated search, and single sign-on. ¶ CON8886 - Content Consolidation: Save Money, Increase Efficiency, and Eliminate Silos Organizations are looking for ways to save money and be more efficient. With content in many different places, it’s difficult to know where to look for a document and whether the document is the most current version. With Oracle WebCenter, content can be consolidated into one best-of-breed repository that is secure, scalable, and integrated with your business processes and applications. Users can find the content they need, where they need it, and ensure that it is the right content. This session covers content challenges that affect your business; content consolidation that can lead to savings in storage and administration costs and can lower risks; and how companies are realizing savings. ¶ CON8911 - Improve Online Experiences for Customers and Partners with Self-Service Portals Are you able to provide your customers and partners an easy-to-use online self-service experience? Are you processing high-volume transactions and struggling with call center bottlenecks or back-end systems that won’t integrate, causing order delays and customer frustration? Are you looking to target content such as product and service offerings to your end users? This session shares approaches to providing targeted delivery as well as strategies and best practices for transforming your business by providing an intuitive user experience for your customers and partners. ¶ CON6156 - Top 10 Ways to Integrate Oracle WebCenter Content This session covers 10 common ways to integrate Oracle WebCenter Content with other enterprise applications and middleware. It discusses out-of-the-box modules that provide expanded features in Oracle WebCenter Content—such as enterprise search, SOA, and BPEL—as well as developer tools you can use to create custom integrations. The presentation also gives guidance on which integration option may work best in your environment. ¶ HOL10207 - Build an Intranet Portal with Oracle WebCenter In this hands-on lab, you’ll work with Oracle WebCenter Portal and Oracle WebCenter Content to build out an enterprise portal that maximizes the productivity of teams and individual contributors. Using browser-based tools, you’ll manage site resources such as page styles, templates, and navigation. You’ll edit content stored in Oracle WebCenter Content directly from your portal. You’ll also experience the latest features that promote collaboration, social networking, and personal productivity. ¶ CON7817 - Migration to Oracle WebCenter Imaging 11g Customers today continually strive to automate business processes, reduce costs, and improve efficiency. The accounts payable process—which is often distributed in nature, requires many approvals, and generates huge volumes of paper invoices—is automated by many customers. In this session, learn how Oracle and SYSTIME have partnered to help a customer migrate its existing Oracle Imaging and Process Management Release 7.6 to the latest Oracle WebCenter Imaging 11g and integrate it with Oracle’s JD Edwards family of products. ¶ CON8910 - How to Engage Customers Across Web, Mobile, and Social Channels Whether on desktops at the office, on tablets at home, or on mobile phones when on the go, today’s customers are always connected. To engage today’s customers, you need to make the online customer experience connected and consistent across a host of devices and multiple channels, including Web, mobile, and social networks. Managing this multichannel environment can result in lots of headaches without the right tools. Attend this session to learn how Oracle WebCenter Sites solves the challenge of multichannel customer engagement. ¶ HOL10206 - Oracle WebCenter Sites 11g: Transforming the Content Contributor Experience Oracle WebCenter Sites 11g makes it easy for marketers and business users to contribute to and manage Websites with the new visual, contextual, and intuitive Web authoring interface. In this hands-on lab, you will create and manage content for a sports-themed Website, using many of the new and enhanced features of the 11g release. ¶ CON8900 - Building Next-Generation Portals: An Interactive Customer Panel Discussion Social and collaborative technologies have changed how people interact, learn, and collaborate, and providing a modern, social Web presence is imperative to remain competitive in today’s market. Can your business benefit from a more collaborative and interactive portal environment for employees, customers, and partners? Attend this session to hear from Oracle WebCenter Portal customers as they share their strategies and best practices for providing users with a modern experience that adapts to their needs and includes personalized access to content in context. The panel also addresses how customers have benefited from creating next-generation portals by migrating from older portal technologies to Oracle WebCenter Portal. ¶ CON9625 - Taking Control of Oracle WebCenter Security Organizations are increasingly looking to extend their Oracle WebCenter portal for social business, to serve external users and provide seamless access to the right information. In particular, many organizations are extending Oracle WebCenter in a business-to-business scenario requiring secure identification and authorization of business partners and their users. This session focuses on how customers are leveraging, securing, and providing access control to Oracle WebCenter portal and mobile solutions. You will learn best practices and hear real-world examples of how to provide flexible and granular access control for Oracle WebCenter deployments, using Oracle Platform Security Services and Oracle Access Management Suite product offerings. ¶ CON8891 - Extending Social into Enterprise Applications and Business Processes Oracle Social Network is an extensible social platform that enables contextual collaboration within enterprise applications and business processes, providing relevant data from across various enterprise systems in one place. Attend this session to see how an Oracle Social Network customer is integrating multiple applications—such as CRM, HCM, and business processes—into Oracle Social Network and Oracle WebCenter to enable individuals and teams to solve complex cross-organizational business problems more effectively by utilizing the social enterprise. ¶ Thursday, October 4th CON8899 - Becoming a Social Business: Stories from the Front Lines of Change What does it really mean to be a social business? How can you change our organization to embrace social approaches? What pitfalls do you need to avoid? In this lively panel discussion, customer and industry thought leaders in social business explore these topics and more as they share their stories of the good, the bad, and the ugly that can happen when embracing social methods and technologies to improve business success. Using moderated questions and open Q&A from the audience, the panel discusses vital topics such as the critical factors for success, the major issues to avoid, how to gain senior executive support for social efforts, how to handle undesired behavior, and how to measure business impact. It takes a thought-provoking look at becoming a social business from the inside. ¶ CON6851 - Oracle WebCenter and Oracle Business Intelligence Enterprise Edition to Create Vendor Portals Large manufacturers of grocery items routinely find themselves depending on the inventory management expertise of their wholesalers and distributors. Inventory costs can be managed more efficiently by the manufacturers if they have better insight into the inventory levels of items carried by their distributors. This creates a unique opportunity for distributors and wholesalers to leverage this knowledge into a revenue-generating subscription service. Oracle Business Intelligence Enterprise Edition and Oracle WebCenter Portal play a key part in enabling creation of business-managed business intelligence portals for vendors. This session discusses one customer that implemented this by leveraging Oracle WebCenter and Oracle Business Intelligence Enterprise Edition. ¶ CON8879 - Provide a Personalized and Consistent Customer Experience in Your Websites and Portals Your customers engage with your company online in different ways throughout their journey—from prospecting by acquiring information on your corporate Website to transacting through self-service applications on your customer portal—and then the cycle begins again when they look for new products and services. Ensuring that the customer experience is consistent and personalized across online properties—from branding and content to interactions and transactions—can be a daunting task. Oracle WebCenter enables you to speak and interact with your customers with one voice across your Websites and portals by providing an integrated platform for delivery of self-service and engagement that unifies and personalizes the online experience. Learn more in this session. ¶ CON8898 - Land Mines, Potholes, and Dirt Roads: Navigating the Way to ECM Nirvana Ten years ago, people were predicting that by this time in history, we’d be some kind of utopian paperless society. As we all know, we’re not there yet, but are we getting closer? What is keeping companies from driving down the road to enterprise content management bliss? Most people understand that using ECM as a central platform enables organizations to expedite document-centric processes, but most business processes in organizations are still heavily paper-based. Many of these processes could be automated and improved with an ECM platform infrastructure. In this panel discussion, you’ll hear from Oracle WebCenter customers that have already solved some of these challenges as they share their strategies for success and roads to avoid along your journey. ¶ CON8908 - Oracle WebCenter Portal: Creating and Using Content Presenter Templates Oracle WebCenter Portal applications use task flows to display and integrate content stored in the Oracle WebCenter Content server. Among the most flexible task flows is Content Presenter, which renders various types of content on an Oracle WebCenter Portal page. Although Oracle WebCenter Portal comes with a set of predefined Content Presenter templates, developers can create their own templates for specific rendering needs. This session shows the lifecycle of developing Content Presenter task flows, including how to create, package, import, modify at runtime, and use such templates. In addition to simple examples with Oracle Application Development Framework (Oracle ADF) UI elements to render the content, it shows how to use other UI technologies, CSS files, and JavaScript libraries. ¶ CON8897 - Using Web Experience Management to Drive Online Marketing Success Every year, the online channel becomes more imperative for driving organizational top-line revenue, but for many companies, mastering how to best market their products and services in a fast-evolving online world with high customer expectations for personalized experiences can be a complex proposition. Come to this panel discussion, and hear directly from online marketers how they are succeeding today by using Web experience management to drive marketing success, using capabilities such as targeting and optimization, user-generated content, mobile site publishing, and site visitor personalization to deliver engaging online experiences. ¶ CON8892 - Oracle’s Journey to Social Business Social business is a revolution, one that is causing rapidly accelerating change in how companies and customers engage with one another and how employees work together. Oracle’s goal in becoming a social business is to create a socially connected organization in which working collaboratively across geographical locations, lines of business, and management chains is second nature, enabling innovative solutions to business challenges. We can achieve this by connecting the right people, finding the right content, communicating with the right people, collaborating at the right time, and building the right communities in the right context—all ready in the CLOUD. Attend this session to see how Oracle is transforming itself into a social business. ¶  ------------ If you've read all the way to the end here - we are REALLY looking forward to seeing you in San Francisco.

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  • Parallelism in .NET – Part 5, Partitioning of Work

    - by Reed
    When parallelizing any routine, we start by decomposing the problem.  Once the problem is understood, we need to break our work into separate tasks, so each task can be run on a different processing element.  This process is called partitioning. Partitioning our tasks is a challenging feat.  There are opposing forces at work here: too many partitions adds overhead, too few partitions leaves processors idle.  Trying to work the perfect balance between the two extremes is the goal for which we should aim.  Luckily, the Task Parallel Library automatically handles much of this process.  However, there are situations where the default partitioning may not be appropriate, and knowledge of our routines may allow us to guide the framework to making better decisions. First off, I’d like to say that this is a more advanced topic.  It is perfectly acceptable to use the parallel constructs in the framework without considering the partitioning taking place.  The default behavior in the Task Parallel Library is very well-behaved, even for unusual work loads, and should rarely be adjusted.  I have found few situations where the default partitioning behavior in the TPL is not as good or better than my own hand-written partitioning routines, and recommend using the defaults unless there is a strong, measured, and profiled reason to avoid using them.  However, understanding partitioning, and how the TPL partitions your data, helps in understanding the proper usage of the TPL. I indirectly mentioned partitioning while discussing aggregation.  Typically, our systems will have a limited number of Processing Elements (PE), which is the terminology used for hardware capable of processing a stream of instructions.  For example, in a standard Intel i7 system, there are four processor cores, each of which has two potential hardware threads due to Hyperthreading.  This gives us a total of 8 PEs – theoretically, we can have up to eight operations occurring concurrently within our system. In order to fully exploit this power, we need to partition our work into Tasks.  A task is a simple set of instructions that can be run on a PE.  Ideally, we want to have at least one task per PE in the system, since fewer tasks means that some of our processing power will be sitting idle.  A naive implementation would be to just take our data, and partition it with one element in our collection being treated as one task.  When we loop through our collection in parallel, using this approach, we’d just process one item at a time, then reuse that thread to process the next, etc.  There’s a flaw in this approach, however.  It will tend to be slower than necessary, often slower than processing the data serially. The problem is that there is overhead associated with each task.  When we take a simple foreach loop body and implement it using the TPL, we add overhead.  First, we change the body from a simple statement to a delegate, which must be invoked.  In order to invoke the delegate on a separate thread, the delegate gets added to the ThreadPool’s current work queue, and the ThreadPool must pull this off the queue, assign it to a free thread, then execute it.  If our collection had one million elements, the overhead of trying to spawn one million tasks would destroy our performance. The answer, here, is to partition our collection into groups, and have each group of elements treated as a single task.  By adding a partitioning step, we can break our total work into small enough tasks to keep our processors busy, but large enough tasks to avoid overburdening the ThreadPool.  There are two clear, opposing goals here: Always try to keep each processor working, but also try to keep the individual partitions as large as possible. When using Parallel.For, the partitioning is always handled automatically.  At first, partitioning here seems simple.  A naive implementation would merely split the total element count up by the number of PEs in the system, and assign a chunk of data to each processor.  Many hand-written partitioning schemes work in this exactly manner.  This perfectly balanced, static partitioning scheme works very well if the amount of work is constant for each element.  However, this is rarely the case.  Often, the length of time required to process an element grows as we progress through the collection, especially if we’re doing numerical computations.  In this case, the first PEs will finish early, and sit idle waiting on the last chunks to finish.  Sometimes, work can decrease as we progress, since previous computations may be used to speed up later computations.  In this situation, the first chunks will be working far longer than the last chunks.  In order to balance the workload, many implementations create many small chunks, and reuse threads.  This adds overhead, but does provide better load balancing, which in turn improves performance. The Task Parallel Library handles this more elaborately.  Chunks are determined at runtime, and start small.  They grow slowly over time, getting larger and larger.  This tends to lead to a near optimum load balancing, even in odd cases such as increasing or decreasing workloads.  Parallel.ForEach is a bit more complicated, however. When working with a generic IEnumerable<T>, the number of items required for processing is not known in advance, and must be discovered at runtime.  In addition, since we don’t have direct access to each element, the scheduler must enumerate the collection to process it.  Since IEnumerable<T> is not thread safe, it must lock on elements as it enumerates, create temporary collections for each chunk to process, and schedule this out.  By default, it uses a partitioning method similar to the one described above.  We can see this directly by looking at the Visual Partitioning sample shipped by the Task Parallel Library team, and available as part of the Samples for Parallel Programming.  When we run the sample, with four cores and the default, Load Balancing partitioning scheme, we see this: The colored bands represent each processing core.  You can see that, when we started (at the top), we begin with very small bands of color.  As the routine progresses through the Parallel.ForEach, the chunks get larger and larger (seen by larger and larger stripes). Most of the time, this is fantastic behavior, and most likely will out perform any custom written partitioning.  However, if your routine is not scaling well, it may be due to a failure in the default partitioning to handle your specific case.  With prior knowledge about your work, it may be possible to partition data more meaningfully than the default Partitioner. There is the option to use an overload of Parallel.ForEach which takes a Partitioner<T> instance.  The Partitioner<T> class is an abstract class which allows for both static and dynamic partitioning.  By overriding Partitioner<T>.SupportsDynamicPartitions, you can specify whether a dynamic approach is available.  If not, your custom Partitioner<T> subclass would override GetPartitions(int), which returns a list of IEnumerator<T> instances.  These are then used by the Parallel class to split work up amongst processors.  When dynamic partitioning is available, GetDynamicPartitions() is used, which returns an IEnumerable<T> for each partition.  If you do decide to implement your own Partitioner<T>, keep in mind the goals and tradeoffs of different partitioning strategies, and design appropriately. The Samples for Parallel Programming project includes a ChunkPartitioner class in the ParallelExtensionsExtras project.  This provides example code for implementing your own, custom allocation strategies, including a static allocator of a given chunk size.  Although implementing your own Partitioner<T> is possible, as I mentioned above, this is rarely required or useful in practice.  The default behavior of the TPL is very good, often better than any hand written partitioning strategy.

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  • SSIS Lookup component tuning tips

    - by jamiet
    Yesterday evening I attended a London meeting of the UK SQL Server User Group at Microsoft’s offices in London Victoria. As usual it was both a fun and informative evening and in particular there seemed to be a few questions arising about tuning the SSIS Lookup component; I rattled off some comments and figured it would be prudent to drop some of them into a dedicated blog post, hence the one you are reading right now. Scene setting A popular pattern in SSIS is to use a Lookup component to determine whether a record in the pipeline already exists in the intended destination table or not and I cover this pattern in my 2006 blog post Checking if a row exists and if it does, has it changed? (note to self: must rewrite that blog post for SSIS2008). Fundamentally the SSIS lookup component (when using FullCache option) sucks some data out of a database and holds it in memory so that it can be compared to data in the pipeline. One of the big benefits of using SSIS dataflows is that they process data one buffer at a time; that means that not all of the data from your source exists in the dataflow at the same time and is why a SSIS dataflow can process data volumes that far exceed the available memory. However, that only applies to data in the pipeline; for reasons that are hopefully obvious ALL of the data in the lookup set must exist in the memory cache for the duration of the dataflow’s execution which means that any memory used by the lookup cache will not be available to be used as a pipeline buffer. Moreover, there’s an obvious correlation between the amount of data in the lookup cache and the time it takes to charge that cache; the more data you have then the longer it will take to charge and the longer you have to wait until the dataflow actually starts to do anything. For these reasons your goal is simple: ensure that the lookup cache contains as little data as possible. General tips Here is a simple tick list you can follow in order to tune your lookups: Use a SQL statement to charge your cache, don’t just pick a table from the dropdown list made available to you. (Read why in SELECT *... or select from a dropdown in an OLE DB Source component?) Only pick the columns that you need, ignore everything else Make the database columns that your cache is populated from as narrow as possible. If a column is defined as VARCHAR(20) then SSIS will allocate 20 bytes for every value in that column – that is a big waste if the actual values are significantly less than 20 characters in length. Do you need DT_WSTR typed columns or will DT_STR suffice? DT_WSTR uses twice the amount of space to hold values that can be stored using a DT_STR so if you can use DT_STR, consider doing so. Same principle goes for the numerical datatypes DT_I2/DT_I4/DT_I8. Only populate the cache with data that you KNOW you will need. In other words, think about your WHERE clause! Thinking outside the box It is tempting to build a large monolithic dataflow that does many things, one of which is a Lookup. Often though you can make better use of your available resources by, well, mixing things up a little and here are a few ideas to get your creative juices flowing: There is no rule that says everything has to happen in a single dataflow. If you have some particularly resource intensive lookups then consider putting that lookup into a dataflow all of its own and using raw files to pass the pipeline data in and out of that dataflow. Know your data. If you think, for example, that the majority of your incoming rows will match with only a small subset of your lookup data then consider chaining multiple lookup components together; the first would use a FullCache containing that data subset and the remaining data that doesn’t find a match could be passed to a second lookup that perhaps uses a NoCache lookup thus negating the need to pull all of that least-used lookup data into memory. Do you need to process all of your incoming data all at once? If you can process different partitions of your data separately then you can partition your lookup cache as well. For example, if you are using a lookup to convert a location into a [LocationId] then why not process your data one region at a time? This will mean your lookup cache only has to contain data for the location that you are currently processing and with the ability of the Lookup in SSIS2008 and beyond to charge the cache using a dynamically built SQL statement you’ll be able to achieve it using the same dataflow and simply loop over it using a ForEach loop. Taking the previous data partitioning idea further … a dataflow can contain more than one data path so why not split your data using a conditional split component and, again, charge your lookup caches with only the data that they need for that partition. Lookups have two uses: to (1) find a matching row from the lookup set and (2) put attributes from that matching row into the pipeline. Ask yourself, do you need to do these two things at the same time? After all once you have the key column(s) from your lookup set then you can use that key to get the rest of attributes further downstream, perhaps even in another dataflow. Are you using the same lookup data set multiple times? If so, consider the file caching option in SSIS 2008 and beyond. Above all, experiment and be creative with different combinations. You may be surprised at what works. Final  thoughts If you want to know more about how the Lookup component differs in SSIS2008 from SSIS2005 then I have a dedicated blog post about that at Lookup component gets a makeover. I am on a mini-crusade at the moment to get a BULK MERGE feature into the database engine, the thinking being that if the database engine can quickly merge massive amounts of data in a similar manner to how it can insert massive amounts using BULK INSERT then that’s a lot of work that wouldn’t have to be done in the SSIS pipeline. If you think that is a good idea then go and vote for BULK MERGE on Connect. If you have any other tips to share then please stick them in the comments. Hope this helps! @Jamiet Share this post: email it! | bookmark it! | digg it! | reddit! | kick it! | live it!

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  • A Guided Tour of Complexity

    - by JoshReuben
    I just re-read Complexity – A Guided Tour by Melanie Mitchell , protégé of Douglas Hofstadter ( author of “Gödel, Escher, Bach”) http://www.amazon.com/Complexity-Guided-Tour-Melanie-Mitchell/dp/0199798109/ref=sr_1_1?ie=UTF8&qid=1339744329&sr=8-1 here are some notes and links:   Evolved from Cybernetics, General Systems Theory, Synergetics some interesting transdisciplinary fields to investigate: Chaos Theory - http://en.wikipedia.org/wiki/Chaos_theory – small differences in initial conditions (such as those due to rounding errors in numerical computation) yield widely diverging outcomes for chaotic systems, rendering long-term prediction impossible. System Dynamics / Cybernetics - http://en.wikipedia.org/wiki/System_Dynamics – study of how feedback changes system behavior Network Theory - http://en.wikipedia.org/wiki/Network_theory – leverage Graph Theory to analyze symmetric  / asymmetric relations between discrete objects Algebraic Topology - http://en.wikipedia.org/wiki/Algebraic_topology – leverage abstract algebra to analyze topological spaces There are limits to deterministic systems & to computation. Chaos Theory definitely applies to training an ANN (artificial neural network) – different weights will emerge depending upon the random selection of the training set. In recursive Non-Linear systems http://en.wikipedia.org/wiki/Nonlinear_system – output is not directly inferable from input. E.g. a Logistic map: Xt+1 = R Xt(1-Xt) Different types of bifurcations, attractor states and oscillations may occur – e.g. a Lorenz Attractor http://en.wikipedia.org/wiki/Lorenz_system Feigenbaum Constants http://en.wikipedia.org/wiki/Feigenbaum_constants express ratios in a bifurcation diagram for a non-linear map – the convergent limit of R (the rate of period-doubling bifurcations) is 4.6692016 Maxwell’s Demon - http://en.wikipedia.org/wiki/Maxwell%27s_demon - the Second Law of Thermodynamics has only a statistical certainty – the universe (and thus information) tends towards entropy. While any computation can theoretically be done without expending energy, with finite memory, the act of erasing memory is permanent and increases entropy. Life & thought is a counter-example to the universe’s tendency towards entropy. Leo Szilard and later Claude Shannon came up with the Information Theory of Entropy - http://en.wikipedia.org/wiki/Entropy_(information_theory) whereby Shannon entropy quantifies the expected value of a message’s information in bits in order to determine channel capacity and leverage Coding Theory (compression analysis). Ludwig Boltzmann came up with Statistical Mechanics - http://en.wikipedia.org/wiki/Statistical_mechanics – whereby our Newtonian perception of continuous reality is a probabilistic and statistical aggregate of many discrete quantum microstates. This is relevant for Quantum Information Theory http://en.wikipedia.org/wiki/Quantum_information and the Physics of Information - http://en.wikipedia.org/wiki/Physical_information. Hilbert’s Problems http://en.wikipedia.org/wiki/Hilbert's_problems pondered whether mathematics is complete, consistent, and decidable (the Decision Problem – http://en.wikipedia.org/wiki/Entscheidungsproblem – is there always an algorithm that can determine whether a statement is true).  Godel’s Incompleteness Theorems http://en.wikipedia.org/wiki/G%C3%B6del's_incompleteness_theorems  proved that mathematics cannot be both complete and consistent (e.g. “This statement is not provable”). Turing through the use of Turing Machines (http://en.wikipedia.org/wiki/Turing_machine symbol processors that can prove mathematical statements) and Universal Turing Machines (http://en.wikipedia.org/wiki/Universal_Turing_machine Turing Machines that can emulate other any Turing Machine via accepting programs as well as data as input symbols) that computation is limited by demonstrating the Halting Problem http://en.wikipedia.org/wiki/Halting_problem (is is not possible to know when a program will complete – you cannot build an infinite loop detector). You may be used to thinking of 1 / 2 / 3 dimensional systems, but Fractal http://en.wikipedia.org/wiki/Fractal systems are defined by self-similarity & have non-integer Hausdorff Dimensions !!!  http://en.wikipedia.org/wiki/List_of_fractals_by_Hausdorff_dimension – the fractal dimension quantifies the number of copies of a self similar object at each level of detail – eg Koch Snowflake - http://en.wikipedia.org/wiki/Koch_snowflake Definitions of complexity: size, Shannon entropy, Algorithmic Information Content (http://en.wikipedia.org/wiki/Algorithmic_information_theory - size of shortest program that can generate a description of an object) Logical depth (amount of info processed), thermodynamic depth (resources required). Complexity is statistical and fractal. John Von Neumann’s other machine was the Self-Reproducing Automaton http://en.wikipedia.org/wiki/Self-replicating_machine  . Cellular Automata http://en.wikipedia.org/wiki/Cellular_automaton are alternative form of Universal Turing machine to traditional Von Neumann machines where grid cells are locally synchronized with their neighbors according to a rule. Conway’s Game of Life http://en.wikipedia.org/wiki/Conway's_Game_of_Life demonstrates various emergent constructs such as “Glider Guns” and “Spaceships”. Cellular Automatons are not practical because logical ops require a large number of cells – wasteful & inefficient. There are no compilers or general program languages available for Cellular Automatons (as far as I am aware). Random Boolean Networks http://en.wikipedia.org/wiki/Boolean_network are extensions of cellular automata where nodes are connected at random (not to spatial neighbors) and each node has its own rule –> they demonstrate the emergence of complex  & self organized behavior. Stephen Wolfram’s (creator of Mathematica, so give him the benefit of the doubt) New Kind of Science http://en.wikipedia.org/wiki/A_New_Kind_of_Science proposes the universe may be a discrete Finite State Automata http://en.wikipedia.org/wiki/Finite-state_machine whereby reality emerges from simple rules. I am 2/3 through this book. It is feasible that the universe is quantum discrete at the plank scale and that it computes itself – Digital Physics: http://en.wikipedia.org/wiki/Digital_physics – a simulated reality? Anyway, all behavior is supposedly derived from simple algorithmic rules & falls into 4 patterns: uniform , nested / cyclical, random (Rule 30 http://en.wikipedia.org/wiki/Rule_30) & mixed (Rule 110 - http://en.wikipedia.org/wiki/Rule_110 localized structures – it is this that is interesting). interaction between colliding propagating signal inputs is then information processing. Wolfram proposes the Principle of Computational Equivalence - http://mathworld.wolfram.com/PrincipleofComputationalEquivalence.html - all processes that are not obviously simple can be viewed as computations of equivalent sophistication. Meaning in information may emerge from analogy & conceptual slippages – see the CopyCat program: http://cognitrn.psych.indiana.edu/rgoldsto/courses/concepts/copycat.pdf Scale Free Networks http://en.wikipedia.org/wiki/Scale-free_network have a distribution governed by a Power Law (http://en.wikipedia.org/wiki/Power_law - much more common than Normal Distribution). They are characterized by hubs (resilience to random deletion of nodes), heterogeneity of degree values, self similarity, & small world structure. They grow via preferential attachment http://en.wikipedia.org/wiki/Preferential_attachment – tipping points triggered by positive feedback loops. 2 theories of cascading system failures in complex systems are Self-Organized Criticality http://en.wikipedia.org/wiki/Self-organized_criticality and Highly Optimized Tolerance http://en.wikipedia.org/wiki/Highly_optimized_tolerance. Computational Mechanics http://en.wikipedia.org/wiki/Computational_mechanics – use of computational methods to study phenomena governed by the principles of mechanics. This book is a great intuition pump, but does not cover the more mathematical subject of Computational Complexity Theory – http://en.wikipedia.org/wiki/Computational_complexity_theory I am currently reading this book on this subject: http://www.amazon.com/Computational-Complexity-Christos-H-Papadimitriou/dp/0201530821/ref=pd_sim_b_1   stay tuned for that review!

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  • CodePlex Daily Summary for Tuesday, March 23, 2010

    CodePlex Daily Summary for Tuesday, March 23, 2010New Projects.NET StarCraft II Replay Parser: A .NET 3.5 Library used to parse StarCraft II replays. Developed in C# 3.5.BackToBasics "B2B" Chat: With technology and software getting more and more complicated, why not get back to basics with BackToBasicsChat. B2B allows you to chat over a ser...Dark Neuron Game Engine: Dark Neuron allows you to easily create fun and interesting games with no need of developing basic game components. This engine is developed for C#...DeepZoom Pivot Constructor: Library to make building DeepZoom images and Pivot displays simpler.ePaper reader: The project is aimed at creating a tool which helps in reading electronic editions of news papers(pdf/flash)FSharpPageProvider for EPiServer CMS 6: This project starts as the port of EPiServer XmlPageProvider to F# programming language. Hammock for REST: Hammock is a REST library for .NET that greatly simplifies consuming and wrapping RESTful services.Kirill Osenkov: Various small projects, tools, utilities and samples by Kirill OsenkovliveDB: liveDB - web client for sql serverLucilla Framework: lucilla frameworkMVC Foolproof Validation: MVC Foolproof Validation aims to extend the Data Annotation validation provided in ASP.NET MVC. Initial efforts are focused on adding contingent va...MVC2Forums: MVC2Forums is simply a forum system based upon MVC2.Mvvm Foundation Silverlight: Mvvm Foundation Silverlight is a library of classes that are helpful when building Silverlight applications based in the MVVM pattern. This librar...MyPersonalWebsite: This is my personal web site developed using ASP.NET MVC 2Planner: Planner makes it easier for all peoples to plan your tasks. It's developed in Delphi.Prose: Prose is an playground for an experimental JavaScript like language compiler. Eventually it will implement 0-CFA, CFA2, and a Tracing JITQuestTracker: QuestTracker is a todo list presented in the format of a quest tracking list such as the one in World of Warcraft.SevenZipLib: SevenZipLib is a C# interface to the 7-zip library.SimpleGeo .Net: .Net Client library for the SimpleGeo.com serviceNew ReleasesAutenticar no OpenLDAP utilizando pGIna: DLL LDAPAuth Plus: New Group: No LoginBMap.NET: BMap.NET 2: This is the 2nd version of BMap.NET. It has included these tags: Bing Maps, and "About BMap.NET".Cronos: Version 2.04: This is primarily a bug-fix release. Several numerical issues have been resolved, and a resource leak (of MS Windows graphics objects) has been fi...EV Dashboard: v1.0: This release includes support for an App.config file and Auto Connect, which will connect to the specified BMS at startup. 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Supported files: tasks.data (v1.3.6 client)VCC: Latest build, v2.1.30322.0: Automatic drop of latest buildVisual Studio DSite: Advanced Notepad (Visual C++ 2008): An notepad written in c that can save in a rich text file format.Wallpaper Rotator: Wallpaper Rotator 0.5: Wallpaper Rotator 0.5 This version includes the following improvements: Saving the choice of "Random Order (Shuffle Mode)" Updating the configu...Most Popular ProjectsMetaSharpRawrWBFS ManagerSilverlight ToolkitASP.NET Ajax LibraryMicrosoft SQL Server Product Samples: DatabaseAJAX Control ToolkitLiveUpload to FacebookWindows Presentation Foundation (WPF)ASP.NETMost Active ProjectsRawrjQuery Library for SharePoint Web ServicesBlogEngine.NETLINQ to TwitterPHPExcelFarseer Physics EngineFacebook Developer ToolkitNB_Store - Free DotNetNuke Ecommerce Catalog Modulepatterns & practices: Composite WPF and SilverlightN2 CMS

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  • Oracle Expands Sun Blade Portfolio for Cloud and Highly Virtualized Environments

    - by Ferhat Hatay
    Oracle announced the expansion of Sun Blade Portfolio for cloud and highly virtualized environments that deliver powerful performance and simplified management as tightly integrated systems.  Along with the SPARC T3-1B blade server, Oracle VM blade cluster reference configuration and Oracle's optimized solution for Oracle WebLogic Suite, Oracle introduced the dual-node Sun Blade X6275 M2 server module with some impressive benchmark results.   Benchmarks on the Sun Blade X6275 M2 server module demonstrate the outstanding performance characteristics critical for running varied commercial applications used in cloud and highly virtualized environments.  These include best-in-class SPEC CPU2006 results with the Intel Xeon processor 5600 series, six Fluent world records and 1.8 times the price-performance of the IBM Power 755 running NAMD, a prominent bio-informatics workload.   Benchmarks for Sun Blade X6275 M2 server module  SPEC CPU2006  The Sun Blade X6275 M2 server module demonstrated best in class SPECint_rate2006 results for all published results using the Intel Xeon processor 5600 series, with a result of 679.  This result is 97% better than the HP BL460c G7 blade, 80% better than the IBM HS22V blade, and 79% better than the Dell M710 blade.  This result demonstrates the density advantage of the new Oracle's server module for space-constrained data centers.     Sun Blade X6275M2 (2 Nodes, Intel Xeon X5670 2.93GHz) - 679 SPECint_rate2006; HP ProLiant BL460c G7 (2.93 GHz, Intel Xeon X5670) - 347 SPECint_rate2006; IBM BladeCenter HS22V (Intel Xeon X5680)  - 377 SPECint_rate2006; Dell PowerEdge M710 (Intel Xeon X5680, 3.33 GHz) - 380 SPECint_rate2006.  SPEC, SPECint, SPECfp reg tm of Standard Performance Evaluation Corporation. Results from www.spec.org as of 11/24/2010 and this report.    For more specifics about these results, please go to see http://blogs.sun.com/BestPerf   Fluent The Sun Fire X6275 M2 server module produced world-record results on each of the six standard cases in the current "FLUENT 12" benchmark test suite at 8-, 12-, 24-, 32-, 64- and 96-core configurations. These results beat the most recent QLogic score with IBM DX 360 M series platforms and QLogic "Truescale" interconnects.  Results on sedan_4m test case on the Sun Blade X6275 M2 server module are 23% better than the HP C7000 system, and 20% better than the IBM DX 360 M2; Dell has not posted a result for this test case.  Results can be found at the FLUENT website.   ANSYS's FLUENT software solves fluid flow problems, and is based on a numerical technique called computational fluid dynamics (CFD), which is used in the automotive, aerospace, and consumer products industries. The FLUENT 12 benchmark test suite consists of seven models that are well suited for multi-node clustered environments and representative of modern engineering CFD clusters. Vendors benchmark their systems with the principal objective of providing comparative performance information for FLUENT software that, among other things, depends on compilers, optimization, interconnect, and the performance characteristics of the hardware.   FLUENT application performance is representative of other commercial applications that require memory and CPU resources to be available in a scalable cluster-ready format.  FLUENT benchmark has six conventional test cases (eddy_417k, turbo_500k, aircraft_2m, sedan_4m, truck_14m, truck_poly_14m) at various core counts.   All information on the FLUENT website (http://www.fluent.com) is Copyrighted1995-2010 by ANSYS Inc. Results as of November 24, 2010. For more specifics about these results, please go to see http://blogs.sun.com/BestPerf   NAMD Results on the Sun Blade X6275 M2 server module running NAMD (a parallel molecular dynamics code designed for high-performance simulation of large biomolecular systems) show up to a 1.8X better price/performance than IBM's Power 7-based system.  For space-constrained environments, the ultra-dense Sun Blade X6275 M2 server module provides a 1.7X better price/performance per rack unit than IBM's system.     IBM Power 755 4-way Cluster (16U). Total price for cluster: $324,212. See IBM United States Hardware Announcement 110-008, dated February 9, 2010, pp. 4, 21 and 39-46.  Sun Blade X6275 M2 8-Blade Cluster (10U). Total price for cluster:  $193,939. Price/performance and performance/RU comparisons based on f1ATPase molecule test results. Sun Blade X6275 M2 cluster: $3,568/step/sec, 5.435 step/sec/RU. IBM Power 755 cluster: $6,355/step/sec, 3.189 step/sec/U. See http://www-03.ibm.com/systems/power/hardware/reports/system_perf.html. See http://www.ks.uiuc.edu/Research/namd/performance.html for more information, results as of 11/24/10.   For more specifics about these results, please go to see http://blogs.sun.com/BestPerf   Reverse Time Migration The Reverse Time Migration is heavily used in geophysical imaging and modeling for Oil & Gas Exploration.  The Sun Blade X6275 M2 server module showed up to a 40% performance improvement over the previous generation server module with super-linear scalability to 16 nodes for the 9-Point Stencil used in this Reverse Time Migration computational kernel.  The balanced combination of Oracle's Sun Storage 7410 system with the Sun Blade X6275 M2 server module cluster showed linear scalability for the total application throughput, including the I/O and MPI communication, to produce a final 3-D seismic depth imaged cube for interpretation. The final image write time from the Sun Blade X6275 M2 server module nodes to Oracle's Sun Storage 7410 system achieved 10GbE line speed of 1.25 GBytes/second or better performance. Between subsequent runs, the effects of I/O buffer caching on the Sun Blade X6275 M2 server module nodes and write optimized caching on the Sun Storage 7410 system gave up to 1.8 GBytes/second effective write performance. The performance results and characterization of this Reverse Time Migration benchmark could serve as a useful measure for many other I/O intensive commercial applications. 3D VTI Reverse Time Migration Seismic Depth Imaging, see http://blogs.sun.com/BestPerf/entry/3d_vti_reverse_time_migration for more information, results as of 11/14/2010.                            

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  • Setting useLegacyV2RuntimeActivationPolicy At Runtime

    - by Reed
    Version 4.0 of the .NET Framework included a new CLR which is almost entirely backwards compatible with the 2.0 version of the CLR.  However, by default, mixed-mode assemblies targeting .NET 3.5sp1 and earlier will fail to load in a .NET 4 application.  Fixing this requires setting useLegacyV2RuntimeActivationPolicy in your app.Config for the application.  While there are many good reasons for this decision, there are times when this is extremely frustrating, especially when writing a library.  As such, there are (rare) times when it would be beneficial to set this in code, at runtime, as well as verify that it’s running correctly prior to receiving a FileLoadException. Typically, loading a pre-.NET 4 mixed mode assembly is handled simply by changing your app.Config file, and including the relevant attribute in the startup element: <?xml version="1.0" encoding="utf-8" ?> <configuration> <startup useLegacyV2RuntimeActivationPolicy="true"> <supportedRuntime version="v4.0"/> </startup> </configuration> .csharpcode { background-color: #ffffff; font-family: consolas, "Courier New", courier, monospace; color: black; font-size: small } .csharpcode pre { background-color: #ffffff; font-family: consolas, "Courier New", courier, monospace; color: black; font-size: small } .csharpcode pre { margin: 0em } .csharpcode .rem { color: #008000 } .csharpcode .kwrd { color: #0000ff } .csharpcode .str { color: #006080 } .csharpcode .op { color: #0000c0 } .csharpcode .preproc { color: #cc6633 } .csharpcode .asp { background-color: #ffff00 } .csharpcode .html { color: #800000 } .csharpcode .attr { color: #ff0000 } .csharpcode .alt { background-color: #f4f4f4; margin: 0em; width: 100% } .csharpcode .lnum { color: #606060 } This causes your application to run correctly, and load the older, mixed-mode assembly without issues. For full details on what’s happening here and why, I recommend reading Mark Miller’s detailed explanation of this attribute and the reasoning behind it. Before I show any code, let me say: I strongly recommend using the official approach of using app.config to set this policy. That being said, there are (rare) times when, for one reason or another, changing the application configuration file is less than ideal. While this is the supported approach to handling this issue, the CLR Hosting API includes a means of setting this programmatically via the ICLRRuntimeInfo interface.  Normally, this is used if you’re hosting the CLR in a native application in order to set this, at runtime, prior to loading the assemblies.  However, the F# Samples include a nice trick showing how to load this API and bind this policy, at runtime.  This was required in order to host the Managed DirectX API, which is built against an older version of the CLR. This is fairly easy to port to C#.  Instead of a direct port, I also added a little addition – by trapping the COM exception received if unable to bind (which will occur if the 2.0 CLR is already bound), I also allow a runtime check of whether this property was setup properly: public static class RuntimePolicyHelper { public static bool LegacyV2RuntimeEnabledSuccessfully { get; private set; } static RuntimePolicyHelper() { ICLRRuntimeInfo clrRuntimeInfo = (ICLRRuntimeInfo)RuntimeEnvironment.GetRuntimeInterfaceAsObject( Guid.Empty, typeof(ICLRRuntimeInfo).GUID); try { clrRuntimeInfo.BindAsLegacyV2Runtime(); LegacyV2RuntimeEnabledSuccessfully = true; } catch (COMException) { // This occurs with an HRESULT meaning // "A different runtime was already bound to the legacy CLR version 2 activation policy." LegacyV2RuntimeEnabledSuccessfully = false; } } [ComImport] [InterfaceType(ComInterfaceType.InterfaceIsIUnknown)] [Guid("BD39D1D2-BA2F-486A-89B0-B4B0CB466891")] private interface ICLRRuntimeInfo { void xGetVersionString(); void xGetRuntimeDirectory(); void xIsLoaded(); void xIsLoadable(); void xLoadErrorString(); void xLoadLibrary(); void xGetProcAddress(); void xGetInterface(); void xSetDefaultStartupFlags(); void xGetDefaultStartupFlags(); [MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)] void BindAsLegacyV2Runtime(); } } Using this, it’s possible to not only set this at runtime, but also verify, prior to loading your mixed mode assembly, whether this will succeed. In my case, this was quite useful – I am working on a library purely for internal use which uses a numerical package that is supplied with both a completely managed as well as a native solver.  The native solver uses a CLR 2 mixed-mode assembly, but is dramatically faster than the pure managed approach.  By checking RuntimePolicyHelper.LegacyV2RuntimeEnabledSuccessfully at runtime, I can decide whether to enable the native solver, and only do so if I successfully bound this policy. There are some tricks required here – To enable this sort of fallback behavior, you must make these checks in a type that doesn’t cause the mixed mode assembly to be loaded.  In my case, this forced me to encapsulate the library I was using entirely in a separate class, perform the check, then pass through the required calls to that class.  Otherwise, the library will load before the hosting process gets enabled, which in turn will fail. This code will also, of course, try to enable the runtime policy before the first time you use this class – which typically means just before the first time you check the boolean value.  As a result, checking this early on in the application is more likely to allow it to work. Finally, if you’re using a library, this has to be called prior to the 2.0 CLR loading.  This will cause it to fail if you try to use it to enable this policy in a plugin for most third party applications that don’t have their app.config setup properly, as they will likely have already loaded the 2.0 runtime. As an example, take a simple audio player.  The code below shows how this can be used to properly, at runtime, only use the “native” API if this will succeed, and fallback (or raise a nicer exception) if this will fail: public class AudioPlayer { private IAudioEngine audioEngine; public AudioPlayer() { if (RuntimePolicyHelper.LegacyV2RuntimeEnabledSuccessfully) { // This will load a CLR 2 mixed mode assembly this.audioEngine = new AudioEngineNative(); } else { this.audioEngine = new AudioEngineManaged(); } } public void Play(string filename) { this.audioEngine.Play(filename); } } Now – the warning: This approach works, but I would be very hesitant to use it in public facing production code, especially for anything other than initializing your own application.  While this should work in a library, using it has a very nasty side effect: you change the runtime policy of the executing application in a way that is very hidden and non-obvious.

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  • Why Is Vertical Resolution Monitor Resolution so Often a Multiple of 360?

    - by Jason Fitzpatrick
    Stare at a list of monitor resolutions long enough and you might notice a pattern: many of the vertical resolutions, especially those of gaming or multimedia displays, are multiples of 360 (720, 1080, 1440, etc.) But why exactly is this the case? Is it arbitrary or is there something more at work? Today’s Question & Answer session comes to us courtesy of SuperUser—a subdivision of Stack Exchange, a community-driven grouping of Q&A web sites. The Question SuperUser reader Trojandestroy recently noticed something about his display interface and needs answers: YouTube recently added 1440p functionality, and for the first time I realized that all (most?) vertical resolutions are multiples of 360. Is this just because the smallest common resolution is 480×360, and it’s convenient to use multiples? (Not doubting that multiples are convenient.) And/or was that the first viewable/conveniently sized resolution, so hardware (TVs, monitors, etc) grew with 360 in mind? Taking it further, why not have a square resolution? Or something else unusual? (Assuming it’s usual enough that it’s viewable). Is it merely a pleasing-the-eye situation? So why have the display be a multiple of 360? The Answer SuperUser contributor User26129 offers us not just an answer as to why the numerical pattern exists but a history of screen design in the process: Alright, there are a couple of questions and a lot of factors here. Resolutions are a really interesting field of psychooptics meeting marketing. First of all, why are the vertical resolutions on youtube multiples of 360. This is of course just arbitrary, there is no real reason this is the case. The reason is that resolution here is not the limiting factor for Youtube videos – bandwidth is. Youtube has to re-encode every video that is uploaded a couple of times, and tries to use as little re-encoding formats/bitrates/resolutions as possible to cover all the different use cases. For low-res mobile devices they have 360×240, for higher res mobile there’s 480p, and for the computer crowd there is 360p for 2xISDN/multiuser landlines, 720p for DSL and 1080p for higher speed internet. For a while there were some other codecs than h.264, but these are slowly being phased out with h.264 having essentially ‘won’ the format war and all computers being outfitted with hardware codecs for this. Now, there is some interesting psychooptics going on as well. As I said: resolution isn’t everything. 720p with really strong compression can and will look worse than 240p at a very high bitrate. But on the other side of the spectrum: throwing more bits at a certain resolution doesn’t magically make it better beyond some point. There is an optimum here, which of course depends on both resolution and codec. In general: the optimal bitrate is actually proportional to the resolution. So the next question is: what kind of resolution steps make sense? Apparently, people need about a 2x increase in resolution to really see (and prefer) a marked difference. Anything less than that and many people will simply not bother with the higher bitrates, they’d rather use their bandwidth for other stuff. This has been researched quite a long time ago and is the big reason why we went from 720×576 (415kpix) to 1280×720 (922kpix), and then again from 1280×720 to 1920×1080 (2MP). Stuff in between is not a viable optimization target. And again, 1440P is about 3.7MP, another ~2x increase over HD. You will see a difference there. 4K is the next step after that. Next up is that magical number of 360 vertical pixels. Actually, the magic number is 120 or 128. All resolutions are some kind of multiple of 120 pixels nowadays, back in the day they used to be multiples of 128. This is something that just grew out of LCD panel industry. LCD panels use what are called line drivers, little chips that sit on the sides of your LCD screen that control how bright each subpixel is. Because historically, for reasons I don’t really know for sure, probably memory constraints, these multiple-of-128 or multiple-of-120 resolutions already existed, the industry standard line drivers became drivers with 360 line outputs (1 per subpixel). If you would tear down your 1920×1080 screen, I would be putting money on there being 16 line drivers on the top/bottom and 9 on one of the sides. Oh hey, that’s 16:9. Guess how obvious that resolution choice was back when 16:9 was ‘invented’. Then there’s the issue of aspect ratio. This is really a completely different field of psychology, but it boils down to: historically, people have believed and measured that we have a sort of wide-screen view of the world. Naturally, people believed that the most natural representation of data on a screen would be in a wide-screen view, and this is where the great anamorphic revolution of the ’60s came from when films were shot in ever wider aspect ratios. Since then, this kind of knowledge has been refined and mostly debunked. Yes, we do have a wide-angle view, but the area where we can actually see sharply – the center of our vision – is fairly round. Slightly elliptical and squashed, but not really more than about 4:3 or 3:2. So for detailed viewing, for instance for reading text on a screen, you can utilize most of your detail vision by employing an almost-square screen, a bit like the screens up to the mid-2000s. However, again this is not how marketing took it. Computers in ye olden days were used mostly for productivity and detailed work, but as they commoditized and as the computer as media consumption device evolved, people didn’t necessarily use their computer for work most of the time. They used it to watch media content: movies, television series and photos. And for that kind of viewing, you get the most ‘immersion factor’ if the screen fills as much of your vision (including your peripheral vision) as possible. Which means widescreen. But there’s more marketing still. When detail work was still an important factor, people cared about resolution. As many pixels as possible on the screen. SGI was selling almost-4K CRTs! The most optimal way to get the maximum amount of pixels out of a glass substrate is to cut it as square as possible. 1:1 or 4:3 screens have the most pixels per diagonal inch. But with displays becoming more consumery, inch-size became more important, not amount of pixels. And this is a completely different optimization target. To get the most diagonal inches out of a substrate, you want to make the screen as wide as possible. First we got 16:10, then 16:9 and there have been moderately successful panel manufacturers making 22:9 and 2:1 screens (like Philips). Even though pixel density and absolute resolution went down for a couple of years, inch-sizes went up and that’s what sold. Why buy a 19″ 1280×1024 when you can buy a 21″ 1366×768? Eh… I think that about covers all the major aspects here. There’s more of course; bandwidth limits of HDMI, DVI, DP and of course VGA played a role, and if you go back to the pre-2000s, graphics memory, in-computer bandwdith and simply the limits of commercially available RAMDACs played an important role. But for today’s considerations, this is about all you need to know. Have something to add to the explanation? Sound off in the the comments. Want to read more answers from other tech-savvy Stack Exchange users? Check out the full discussion thread here.     

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  • Programação paralela no .NET Framework 4 – Parte I

    - by anobre
    Introdução O avanço de tecnologia nos últimos anos forneceu, a baixo custo, acesso  a workstations com inúmeros CPUs. Facilmente encontramos hoje máquinas clientes com 2, 4 e até 8 núcleos, sem considerar os “super-servidores” com até 36 processadores :) Da wikipedia: A Unidade central de processamento (CPU, de acordo com as iniciais em inglês) ou o processador é a parte de um sistema de computador que executa as instruções de um programa de computador, e é o elemento primordial na execução das funções de um computador. Este termo tem sido usado na indústria de computadores pelo menos desde o início dos anos 1960[1]. A forma, desenho e implementação de CPUs têm mudado dramaticamente desde os primeiros exemplos, mas o seu funcionamento fundamental permanece o mesmo. Fazendo uma analogia, seria muito interessante delegarmos tarefas no mundo real que podem ser executadas independentemente a pessoas diferentes, atingindo desta forma uma  maior performance / produtividade na sua execução. A computação paralela se baseia na idéia que um problema maior pode ser dividido em problemas menores, sendo resolvidos de forma paralela. Este pensamento é utilizado há algum tempo por HPC (High-performance computing), e através das facilidades dos últimos anos, assim como a preocupação com consumo de energia, tornaram esta idéia mais atrativa e de fácil acesso a qualquer ambiente. No .NET Framework A plataforma .NET apresenta um runtime, bibliotecas e ferramentas para fornecer uma base de acesso fácil e rápido à programação paralela, sem trabalhar diretamente com threads e thread pool. Esta série de posts irá apresentar todos os recursos disponíveis, iniciando os estudos pela TPL, ou Task Parallel Library. Task Parallel Library A TPL é um conjunto de tipos localizados no namespace System.Threading e System.Threading.Tasks, a partir da versão 4 do framework. A partir da versão 4 do framework, o TPL é a maneira recomendada para escrever código paralelo e multithreaded. http://msdn.microsoft.com/en-us/library/dd460717(v=VS.100).aspx Task Parallelism O termo “task parallelism”, ou em uma tradução live paralelismo de tarefas, se refere a uma ou mais tarefas sendo executadas de forma simultanea. Considere uma tarefa como um método. A maneira mais fácil de executar tarefas de forma paralela é o código abaixo: Parallel.Invoke(() => TrabalhoInicial(), () => TrabalhoSeguinte()); O que acontece de verdade? Por trás nos panos, esta instrução instancia de forma implícita objetos do tipo Task, responsável por representar uma operação assíncrona, não exatamente paralela: public class Task : IAsyncResult, IDisposable É possível instanciar Tasks de forma explícita, sendo uma alternativa mais complexa ao Parallel.Invoke. var task = new Task(() => TrabalhoInicial()); task.Start(); Outra opção de instanciar uma Task e já executar sua tarefa é: var t = Task<int>.Factory.StartNew(() => TrabalhoInicialComValor());var t2 = Task<int>.Factory.StartNew(() => TrabalhoSeguinteComValor()); A diferença básica entre as duas abordagens é que a primeira tem início conhecido, mais utilizado quando não queremos que a instanciação e o agendamento da execução ocorra em uma só operação, como na segunda abordagem. Data Parallelism Ainda parte da TPL, o Data Parallelism se refere a cenários onde a mesma operação deva ser executada paralelamente em elementos de uma coleção ou array, através de instruções paralelas For e ForEach. A idéia básica é pegar cada elemento da coleção (ou array) e trabalhar com diversas threads concomitantemente. A classe-chave para este cenário é a System.Threading.Tasks.Parallel // Sequential version foreach (var item in sourceCollection) { Process(item); } // Parallel equivalent Parallel.ForEach(sourceCollection, item => Process(item)); Complicado né? :) Demonstração Acesse aqui um vídeo com exemplos (screencast). Cuidado! Apesar da imensa vontade de sair codificando, tome cuidado com alguns problemas básicos de paralelismo. Neste link é possível conhecer algumas situações. Abraços.

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  • Oracle Virtualization at Oracle OpenWorld 2012

    - by Chris Kawalek
    Mini-Series Entry 1 of 3: Hands-On Virtualization This is the first entry of a 3 part mini-series aimed at highlighting server and desktop virtualization at this year’s Oracle OpenWorld.  Oracle OpenWorld 2012 is fast approaching! If you are as excited as we are about the fascinating new Oracle virtualization content featured at Oracle OpenWorld 2012, you won’t want to miss this blog mini-series. We will be highlighting sessions that cover advances and innovations in our products, our product strategy and roadmap, and hands on labs for step-by-step instructions from our field and product experts. In the blog mini-series you will learn about: The Oracle Virtualization general keynote session Hands-on labs  Key Oracle server and desktop virtualization sessions In this entry, we will cover the Oracle Virtualization keynote session and the hands-on labs you won't want to miss. General Session: Oracle Virtualization Strategy and Roadmap Session ID: GEN8725 Oracle offers the industry’s most complete and integrated virtualization portfolio enabling organizations to realize benefits beyond simple consolidation as they transform their data centers into flexible cloud-based infrastructures. Join Oracle executives and experts to learn about Oracle’s desktop-to-data-center virtualization solutions, such as the OS, with built-in management integration at all layers that can help you virtualize and manage the complete computing environment, from physical servers to virtual servers and applications. This “don’t-miss” session offers details of the latest product updates and strategy; product roadmaps; integration with enterprise applications; and real-world examples of how Oracle server, desktop, and storage virtualization is benefiting customers. Here are our top picks for Hands-On Labs for Oracle OpenWorld 2012: Oracle Virtual Desktop Infrastructure Performance and Tablet Mobility Session ID: HOL9907 This hands-on lab demonstrates the performance (using an industry-standard load tester) and roaming capabilities of Oracle Virtual Desktop Infrastructure with Oracle’s Sun Ray Clients, Apple iPad and other clients. Deploying an IaaS Environment with Oracle VM: Hands-On Lab  Session ID: HOL9558 This hands-on lab takes you through the planning and deployment of an infrastructure as a service (IaaS) environment with Oracle VM as the foundation. It covers a range of topics, from planning storage capacity, LUN creation, network bandwidth planning, and best practices to designing and streamlining the environment for ease of management. Learn from deeply experienced field engineers and product experts. Virtualize and Deploy Oracle Applications in Minutes with Oracle VM: Hands-On Lab Session ID: HOL9559 This hands-on lab is for application architects or system administrators who will need to deploy and manage Oracle Applications. You’ll learn how Oracle VM Templates can turn you into a power user who can virtualize and deploy complex Oracle Applications in minutes. Longtime field-experienced engineers and product experts will show you, step by step, how to download and import templates and deploy the applications. x86 Enterprise Cloud Infrastructure with Oracle VM 3.x and Sun ZFS Storage Appliance Session ID: HOL9870 The purpose of this hands-on lab is to demonstrate the functionality and usage of Oracle’s enterprise cloud infrastructure for x86 with Oracle VM 3.x. It covers:  Creation of VMs Migration of VMs  Quick and easy deployment of Oracle applications with Oracle VM Templates  Usage of the Storage Connect plug-in for the Sun ZFS Storage Appliance You can find these and other great sessions on the Oracle OpenWorld 2012 Content Catalogue. Start checking now to better plan and organize your week at the conference. Then you’ll be ready to sign up for all of your sessions in mid-July when the scheduling tool goes live. While the hands-on labs allow you to directly interact with Oracle virtualization products, the conference sessions allow you to hear from a wide variety of industry experts on how they're using they technology in real world deployments, solving specific challenges, and more. In tomorrow's entry, we'll start talking about the many conference sessions related to Oracle server and desktop virtualization you can attend during the show. See you then! - The Oracle Virtualization marketing team

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  • Surface Review from Canadian Guy Who Didn&rsquo;t Go To Build

    - by D'Arcy Lussier
    I didn’t go to Build last week, opted to stay home and go trick-or-treating with my daughters instead. I had many friends that did go however, and I was able to catch up with James Chambers last night to hear about the conference and play with his Surface RT and Nokia 920 WP8 devices. I’ve been using Windows 8 for a while now, so I’m not going to comment on OS features – lots of posts out there on that already. Let me instead comment on the hardware itself. Size and Weight The size of the tablet was awesome. The Windows 8 tablet I’m using to reference this against is the one from Build 2011 (Samsung model) we received as well as my iPad. The Surface RT was taller and slightly heavier than the iPad, but smaller and lighter than the Samsung Win 8 tablet. I still don’t prefer the default wide-screen format, but the Surface RT is much more usable even when holding it by the long edge than the Samsung. Build Quality No issues with the build quality, it seemed very solid. But…y’know, people have been going on about how the Surface RT materials are so much better than the plastic feeling models Samsung and others put out. I didn’t really notice *that* much difference in that regard with the Surface RT. Interesting feature I didn’t expect – the Windows button on the device is touch-sensitive, not a mechanical one. I didn’t try video or anything, so I can’t comment on the media experience. The kickstand is a great feature, and the way the Surface RT connects to the combo case/keyboard touchcover is very slick while being incredibly simple. What About That Touch Cover Keyboard? So first, kudos to Microsoft on the touch cover! This thing was insanely responsive (including the trackpad) and really delivered on the thinness I was expecting. With that said, and remember this is with very limited use, I would probably go with the Type Cover instead of the Touch Cover. The difference is buttons. The Touch Cover doesn’t actually have “buttons” on the keyboard – hence why its a “touch” cover. You tap on a key to type it. James tells me after a while you get used to it and you can type very fast. For me, I just prefer the tactile feeling of a button being pressed/depressed. But still – typing on the touch case worked very well. Would I Buy One? So after playing with it, did I cry out in envy and rage that I wasn’t able to get one of these machines? Did I curse my decision to collect Halloween candy with my kids instead of being at Build getting hardware? Well – no. Even with the keyboard, the Surface RT is not a business laptop replacement device. While Office does come included, you can’t install any other applications outside of Windows Store Apps. This might be limiting depending on what other applications you need to have available on your computer. Surface RT is a great personal computing device, as long as you’re not already invested in a competing ecosystem. I’ve heard people make statements that they’re going to replace all the iPads in their homes with Surface tablets. In my home, that’s not feasible – my wife and daughters have amassed quite a collection of games via iTunes. We also buy all our music via iTunes as well, so even with the XBox streaming music service now available we’re still tied quite tightly to iTunes. So who is the Surface RT for? In my mind, if you’re looking for a solid, compact device that provides basic business functionality (read: email) or if you have someone that needs a very simple to use computer for email, web browsing, etc., then Surface RT is a great option. For me, I’m waiting on the Samsung Ativ Smart PC Pro and am curious to see what changes the Surface Pro will come with.

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  • Oracle’s New Memory-Optimized x86 Servers: Getting the Most Out of Oracle Database In-Memory

    - by Josh Rosen, x86 Product Manager-Oracle
    With the launch of Oracle Database In-Memory, it is now possible to perform real-time analytics operations on your business data as it exists at that moment – in the DRAM of the server – and immediately return completely current and consistent data. The Oracle Database In-Memory option dramatically accelerates the performance of analytics queries by storing data in a highly optimized columnar in-memory format.  This is a truly exciting advance in database technology.As Larry Ellison mentioned in his recent webcast about Oracle Database In-Memory, queries run 100 times faster simply by throwing a switch.  But in order to get the most from the Oracle Database In-Memory option, the underlying server must also be memory-optimized. This week Oracle announced new 4-socket and 8-socket x86 servers, the Sun Server X4-4 and Sun Server X4-8, both of which have been designed specifically for Oracle Database In-Memory.  These new servers use the fastest Intel® Xeon® E7 v2 processors and each subsystem has been designed to be the best for Oracle Database, from the memory, I/O and flash technologies right down to the system firmware.Amongst these subsystems, one of the most important aspects we have optimized with the Sun Server X4-4 and Sun Server X4-8 are their memory subsystems.  The new In-Memory option makes it possible to select which parts of the database should be memory optimized.  You can choose to put a single column or table in memory or, if you can, put the whole database in memory.  The more, the better.  With 3 TB and 6 TB total memory capacity on the Sun Server X4-4 and Sun Server X4-8, respectively, you can memory-optimize more, if not your entire database.   Sun Server X4-8 CMOD with 24 DIMM slots per socket (up to 192 DIMM slots per server) But memory capacity is not the only important factor in selecting the best server platform for Oracle Database In-Memory.  As you put more of your database in memory, a critical performance metric known as memory bandwidth comes into play.  The total memory bandwidth for the server will dictate the rate in which data can be stored and retrieved from memory.  In order to achieve real-time analysis of your data using Oracle Database In-Memory, even under heavy load, the server must be able to handle extreme memory workloads.  With that in mind, the Sun Server X4-8 was designed with the maximum possible memory bandwidth, providing over a terabyte per second of total memory bandwidth.  Likewise, the Sun Server X4-4 also provides extreme memory bandwidth in an even more compact form factor with over half a terabyte per second, providing customers with scalability and choice depending on the size of the database.Beyond the memory subsystem, Oracle’s Sun Server X4-4 and Sun Server X4-8 systems provide other key technologies that enable Oracle Database to run at its best.  The Sun Server X4-4 allows for up 4.8 TB of internal, write-optimized PCIe flash while the Sun Server X4-8 allows for up to 6.4 TB of PCIe flash.  This enables dramatic acceleration of data inserts and updates to Oracle Database.  And with the new elastic computing capability of Oracle’s new x86 servers, server performance can be adapted to your specific Oracle Database workload to ensure that every last bit of processing power is utilized.Because Oracle designs and tests its x86 servers specifically for Oracle workloads, we provide the highest possible performance and reliability when running Oracle Database.  To learn more about Sun Server X4-4 and Sun Server X4-8, you can find more details including data sheets and white papers here. Josh Rosen is a Principal Product Manager for Oracle’s x86 servers, focusing on Oracle’s operating systems and software.  He previously spent more than a decade as a developer and architect of system management software. Josh has worked on system management for many of Oracle's hardware products ranging from the earliest blade systems to the latest Oracle x86 servers. 

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  • How to Install Oracle Software on Remote Linux Server

    - by James Taylor
    It is becoming more common these days to install Oracle software on remote Linux servers. This issue has always existed but was generally resolved either by silent installs or by someone physically going to the server to install the software. This is becoming more difficult with the popular virtualisation and cloud deployment strategies. This post provides the steps involved to install Oracle Software using the GUI interface on a remote Linux server. There are many ways to achieve this, the way I resolve this issue is via Virtual Network Computing (VNC) as it is shipped with RedHat and OEL out of the box. For this post I’m using OEL 5 deployed on a OVM guest. If not already done so download and install a client version of VNC so you can connect to the server. There are many out there, for the purpose of this post I use UltraVNC. You can download a free version from http://www.uvnc.com/download/index.html By default VNC Server is installed in your RedHat and OEL OS, but it is not configured. The way VNC works is when started it creates a client instance for the user and binds it to a specific port. So if have an account on the Linux box you can setup a VNC Server session for that user, you don’t need to be root. For the purpose of this document I’m going to use oracle as the user to setup a VNC Session as this is the user I want use to install the software. However to start the VNC Service you must be root. As the root user run the following command: service vncserver start Starting VNC server: no displays configured                [  OK  ] Login to the Linux box as the user  you wan to install the Oracle software [oracle@lisa ~]$ Run the command to create a new VNC server instance for the oracle user: vncserver You will be ask to supply password information. This is what you will enter when connecting from your desktop client. This password is also independent of the actual Linux user password. The VNC Server is acting as a proxy to this instance. You will require a password to access your desktops. Password: Verify: xauth:  creating new authority file /home/oracle/.Xauthority New 'lisa.nz.oracle.com:1 (oracle)' desktop is lisa.nz.oracle.com:1 Creating default startup script /home/oracle/.vnc/xstartup Starting applications specified in /home/oracle/.vnc/xstartup Log file is /home/oracle/.vnc/lisa.nz.oracle.com:1.log As you can see a new instance lisa.nz.oracle.com:1 has been created. If you were to run the vncserver command again another instance lisa.nz.oracle.com:2 will be created. If you are going through a firewall you will need to ensure that the port 5901 (port 1) is open between your client desktop and the Linux Server. Depending on the options chosen at install time a firewall could be in place. The simplest way to disable this is using the command. You will need to be root. service iptables stop This will stop the firewall while you install. If you just want to add a port to the accepted lists use the firewall UI. You will need to be root. system-config-security-level Now you are ready to connect to the server via the VNC. Using the software installed in step one start the VNC Client. You should be prompted for the server and port. If connectivity is established, you will be prompted for the password entered in step 5. You should now be presented with a terminal screen ready to install software Go to the location of the oracle install software and start the Oracle Universal Installer

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  • Oracle Database 12 c Training and Certification: What’s in it for Me?

    - by KJones
    Oracle Database 12c has officially launched! Through Oracle University, our expert instructors can introduce you to the features and functions of this new Oracle Database 12c product. Through training courses and certification exam prep seminars, you can build up your database knowledge and apply this knowledge to advance your career. Already an Oracle Database Expert? Why Oracle Database 12c Training is still a Good Idea Oracle is the industry leader for database technology and takes the release of new products very seriously. We continue to listen to customer needs and add features and functionality to address those needs. Oracle Database 12c is no exception. The following areas have been greatly enhanced and should be considered for your additional training or certification: • Database for Cloud Computing • Compression and Information Lifecycle Management (ILM) • Improved Performance & Scalability • Extreme Availability • Security Defense in Depth • Manageability Oracle Certified Database Administrators Reap Career Rewards Becoming an expert user of database technology through Oracle University's certification program widens your skill set to demonstrate your expertise implementing the most advanced database technology available. By doing so, you'll make yourself a more marketable employee and candidate in the job market.  Reasons to Become an Oracle Certified Database Administrator of Oracle Database 12c: • The new Oracle Database 12c certifications emphasize more advanced skills that align with industry standards, resulting in an even more valuable credential for customers and partners. • The Oracle Certified Associate (OCA) for Oracle Database 12c centers upon certification objectives that measure IT professionals' day-to-day skills, along with your ability to manage challenges. • Building upon all of the competencies incorporated into Oracle's Database 12c OCA certification, the Oracle Certified Professional (OCP) for Oracle Database 12c certification includes advanced knowledge and skills required of top-performing database administrators. • The Oracle Certified Master (OCM) for Oracle Database 12c - a very challenging and elite top-level certification - certifies the most highly skilled and experienced database experts. • Oracle offers 12c upgrade paths for existing Oracle Certified Professionals (OCP) and Oracle Certified Masters (OCM). Database 12c Training and Certification: Built with Your Input When creating Oracle Database 12c training courses and certifications, we wanted to know which tasks are most important in a DBA's day-to-day work. Instead of assuming what those tasks might be, we decided to develop a job task analysis survey for DBAs. The response rate from DBAs from around the world was overwhelming! The survey focused on the following key database areas: • DBA Core Essentials • Database Storage • High Availability • Scalability • Networking • Security • Very Large Database Administration • Distributed Databases After conducting this survey, we took this specific feedback and used it to help mold the new Oracle Database 12c training and certification curriculum. The benefit to you? You now have access to Oracle Database 12c courses and certification exams that were created with your specific on-the-job tasks in mind. Explore Oracle Database 12c Training & Certification Today Investing in Oracle Database 12c training courses and certifications will help you develop a great deal of knowledge, experience and expertise. Explore our portfolio of offerings to determine which skills you need as a DBA to get up-to-speed on Oracle Database 12c technology. Questions or comments about the new Oracle Database 12c offerings? Let us know in the comments below. - Diana Gray, Principle Curriculum Product Manager and Raza Siddiqui, Senior Principle Curriculum Product Manager

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