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  • How to become a good team player?

    - by Nick
    I've been programming (obsessively) since I was 12. I am fairly knowledgeable across the spectrum of languages out there, from assembly, to C++, to Javascript, to Haskell, Lisp, and Qi. But all of my projects have been by myself. I got my degree in chemical engineering, not CS or computer engineering, but for the first time this fall I'll be working on a large programming project with other people, and I have no clue how to prepare. I've been using Windows all of my life, but this project is going to be very unix-y, so I purchased a Mac recently in the hopes of familiarizing myself with the environment. I was fortunate to participate in a hackathon with some friends this past year -- both CS majors -- and excitingly enough, we won. But I realized as I worked with them that their workflow was very different from mine. They used Git for version control. I had never used it at the time, but I've since learned all that I can about it. They also used a lot of frameworks and libraries. I had to learn what Rails was pretty much overnight for the hackathon (on the other hand, they didn't know what lexical scoping or closures were). All of our code worked well, but they didn't understand mine, and I didn't understand theirs. I hear references to things that real programmers do on a daily basis -- unit testing, code reviews, but I only have the vaguest sense of what these are. I normally don't have many bugs in my little projects, so I have never needed a bug tracking system or tests for them. And the last thing is that it takes me a long time to understand other people's code. Variable naming conventions (that vary with each new language) are difficult (__mzkwpSomRidicAbbrev), and I find the loose coupling difficult. That's not to say I don't loosely couple things -- I think I'm quite good at it for my own work, but when I download something like the Linux kernel or the Chromium source code to look at it, I spend hours trying to figure out how all of these oddly named directories and files connect. It's a programming sin to reinvent the wheel, but I often find it's just quicker to write up the functionality myself than to spend hours dissecting some library. Obviously, people who do this for a living don't have these problems, and I'll need to get to that point myself. Question: What are some steps that I can take to begin "integrating" with everyone else? Thanks!

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  • How employable am I as a programmer?

    - by dsimcha
    I'm currently a Ph.D. student in Biomedical Engineering with a concentration in computational biology and am starting to think about what I want to do after graduate school. I feel like I've accumulated a lot of programming skills while in grad school, but taken a very non-traditional path to learning all this stuff. I'm wondering whether I would have an easy time getting hired as a programmer and could fall back on that if I can't find a good job directly in my field, and if so whether I would qualify for a more prestigious position than "code monkey". Things I Have Going For Me Approximately 4 years of experience programming as part of my research. I believe I have a solid enough grasp of the fundamentals that I could pick up new languages and technologies pretty fast, and could demonstrate this in an interview. Good math and statistics skills. An extensive portfolio of open source work (and the knowledge that working on these projects implies): I wrote a statistics library in D, mostly from scratch. I wrote a parallelism library (parallel map, reduce, foreach, task parallelism, pipelining, etc.) that is currently in review for adoption by the D standard library. I wrote a 2D plotting library for D against the GTK Cairo backend. I currently use it for most of the figures I make for my research. I've contributed several major performance optimizations to the D garbage collector. (Most of these were low-hanging fruit, but it still shows my knowledge of low-level issues like memory management, pointers and bit twiddling.) I've contributed lots of miscellaneous bug fixes to the D standard library and could show the change logs to prove it. (This demonstrates my ability read other people's code.) Things I Have Going Against Me Most of my programming experience is in D and Python. I have very little to virtually no experience in the more established, "enterprise-y" languages like Java, C# and C++, though I have learned a decent amount about these languages from small, one-off projects and discussions about language design in the D community. In general I have absolutely no knowledge of "enterprise-y" technlogies. I've never used a framework before, possibly because most reusable code for scientific work and for D tends to call itself a "library" instead. I have virtually no formal computer science/software engineering training. Almost all of my knowledge comes from talking to programming geek friends, reading blogs, forums, StackOverflow, etc. I have zero professional experience with the official title of "developer", "software engineer", or something similar.

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  • Oracle Customer Success Forum - Batesville - Oracle Sales Cloud - June 24th, 5pm CET

    - by Richard Lefebvre
    Batesville uses Oracle Sales Cloud to create a common platform and standardize processes for business transformation across field sales and telesales. Using real-time KPI dashboards, they are measuring their business success with consistency across their sales reps.We are pleased to invite you to a discussion with Batesville on industry trends, why sales automation is important, reasons for choosing Oracle Sales Cloud, and the vendor evaluation process. Please click on the register button to confirm your attendance by 5:00 p.m. Pacific Time on June 23, 2014.Speakers: Diane Kinker, Director CRM Program Chris Haven, Senior Director Product Management, Oracle (Moderator) Organization Profile:Batesville (www.Batesville.com), a wholly owned subsidiary of Hillenbrand, Inc. (NYSE:HI), is the leader in the North American death care industry. For more than 125 years, Batesville has been dedicated to helping families honor the lives of those they love®. Batesville’s innovation has changed the face of funeral service, from advancements in manufacturing and quality to patented features and memorialization offerings, technology and web-based solutions, and profit-enhancing merchandising systems and room displays. Our history of manufacturing excellence, product innovation, superior customer service and reliable delivery has helped Batesville become – and remain – a market leader. Event Description:In this informal reference call, you will have the opportunity to hear Batesville discuss industry trends, why sales automation is important, the decision making process for choosing Oracle Sales Cloud, and the vendor evaluation process. The call will open with a brief overview, followed by discussion, and an open question and answer session. Please allow one hour for the call.Why Oracle:Batesville looked to transform its sales automation processes. Oracle Sales Cloud met these needs and Batesville’s requirements for: Standardized end-to-end Sales Processes including Sales Performance Management (territory management, quota management and incentive compensation) Mobile capabilities with integration to Microsoft Outlook and Smartphones Creation of the WIG Dashboard (Wildly Important Goal) using reporting and analytics Click the Register Now button to confirm your attendance for this informative event. Registration will close at 5:00 p.m. Pacific Time on June 23, 2014.After you register your information will be forwarded through an Approval Process. Once your registration request has been validated against the invitation database, you will receive an email confirmation with your registration details as long as there is availability. Please be advised that Batesville will revise the registrants list and may dismiss registrations as they see fit. Register Now!

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  • Support ARMv7 instruction set in Windows Embedded Compact applications

    - by Valter Minute
    On of the most interesting new features of Windows Embedded Compact 7 is support for the ARMv5, ARMv6 and ARMv7 instruction sets instead of the ARMv4 “generic” support provided by the previous releases. This means that code build for Windows Embedded Compact 7 can leverage features (like the FPU unit for ARMv6 and v7) and instructions of the recent ARM cores and improve their performances. Those improvements are noticeable in graphics, floating point calculation and data processing. The ARMv7 instruction set is supported by the latest Cortex-A8, A9 and A15 processor families. Those processor are currently used in tablets, smartphones, in-car navigation systems and provide a great amount of processing power and a low amount of electric power making them very interesting for portable device but also for any kind of device that requires a rich user interface, processing power, connectivity and has to keep its power consumption low. The bad news is that the compiler provided with Visual Studio 2008 does not provide support for ARMv7, building native applications using just the ARMv4 instruction set. Porting a Visual Studio “Smart Device” native C/C++ project to Platform Builder is not easy and you’ll lack many of the features that the VS2008 application development environment provides. You’ll also need access to the BSP and OSDesign configuration for your device to be able to build and debug your application inside Platform Builder and this may prevent independent software vendors from using the new compiler to improve their applications performances. Adeneo Embedded now provides a whitepaper and a Visual Studio plug-in that allows usage of the new ARMv7 enabled compiler to build applications inside Visual Studio 2008. I worked on the whitepaper and the tools, with the help of my colleagues and now the results can be downloaded from Adeneo Embedded’s website: http://www.adeneo-embedded.com/OS-Technologies/Windows-Embedded (Click on the “WEC7 ARMv7 Whitepaper tab to access the download links, free registration required) A very basic benchmark showed a very good performance improvement in integer and floating-point operations. Obviously your mileage may vary and we can’t promise the same amount of improvement on any application, but with a small effort on your side (even smaller if you use the plug-in) you can try on your own application. ARMv7 support is provided using Platform Builder’s compiler and VS2008 application debugger is not able to debut ARMv7 code, so you may need to put in place some workaround like keeping ARMv4 code for debugging etc.

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  • Is it okay to have people with multiple roles in a Scrum team?

    - by Wayne M
    I'm evaluating some Agile-style methodologies for possible introduction to my team. With Scrum, is it allowable to have the same person perform multiple roles? We have a small team of four developers and a web designer; we don't really have a lead (I fulfill this role), QA testers or business analysts, and all of our development tasks come from the CIO. Automated testing is seen as a total waste of time, and everything focuses on speed and not quality. What will happen is the CIO will come up with a development task (whether a feature or a bug) and give it to a developer (not to the whole team, to an individual, often in private or out of the blue) who is then expected to get it completed. The CIO doesn't gather requirements beyond the initial idea (and this has bitten us before as we'll implement something only to find out that none of the end users can use the feature, because they weren't consulted or even informed about it before we developed it, and in a panic we'll be told to revert the change) but requires say in/approval of everything that we do. First things first, is a Scrum style something to consider to introduce some standards and practices? From reading, Scrum seems to rely on a bit more trust and communication and focuses more on project management than on development, which is something we are completely devoid of as we don't have any semblance of project management at present. Second, if it can work is it unreasonable for someone, let's say myself, to act as both ScrumMaster and a developer? Or for a developer to also be the Product Owner (although chances are this will be the CIO, who isn't a developer)? I realize the Scrum Master and the Product Owner should be different people but at the same time I don't think we have anyone who has the qualities of a Product Owner (chances are it would turn into a "I need all these stories, I don't care how but get it done" type of deal and/or any freeze would be unfrozen on a whim). It seems to me that I might need to pick and choose pieces of Scrum/XP/Lean to compensate for how things are done currently, as it's highly unlikely that the mentality can be changed; for instance Pair Programming would never fly (seen as a waste, you get half the tasks done if you need two people for everything), TDD would be a hard sell, but short cycles would be welcomed.

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  • Once installed geos library (C++, and C), and then trying to install rgeos package (R), it reports geos-config missing!

    - by user1873888
    Knowing that the package rgeos, from the R language, requieres a prior installation of geos libraries, I installed, both, libgeos and libgeos-c1 (3.2.2), using the synaptic installer in my Ubuntu 12.04 (32 bit) machine. Then I tried to install rgeos directly from the R console, and it issued a message in the sense that geos-config was not found. The output is as follows: > install.packages("rgeos") Installing package(s) into ‘/home/checo/R/i486-pc-linux-gnu-library/2.15’ (as ‘lib’ is unspecified) also installing the dependency ‘sp’ probando la URL 'http://cran.rstudio.com/src/contrib/sp_1.0-9.tar.gz' Content type 'application/x-gzip' length 882102 bytes (861 Kb) URL abierta ================================================== downloaded 861 Kb probando la URL 'http://cran.rstudio.com/src/contrib/rgeos_0.2-19.tar.gz' Content type 'application/x-gzip' length 221471 bytes (216 Kb) URL abierta ================================================== downloaded 216 Kb * installing *source* package ‘sp’ ... ** package ‘sp’ successfully unpacked and MD5 sums checked ** libs gcc -std=gnu99 -I/usr/share/R/include -DNDEBUG -fpic -O3 -pipe -g -c R centroid.c -o Rcentroid.o gcc -std=gnu99 -I/usr/share/R/include -DNDEBUG -fpic -O3 -pipe -g -c gcdist.c -o gcdist.o gcc -std=gnu99 -I/usr/share/R/include -DNDEBUG -fpic -O3 -pipe -g -c init.c -o init.o gcc -std=gnu99 -I/usr/share/R/include -DNDEBUG -fpic -O3 -pipe -g -c pip.c -o pip.o gcc -std=gnu99 -I/usr/share/R/include -DNDEBUG -fpic -O3 -pipe -g -c pip2.c -o pip2.o gcc -std=gnu99 -I/usr/share/R/include -DNDEBUG -fpic -O3 -pipe -g -c sp_xports.c -o sp_xports.o gcc -std=gnu99 -I/usr/share/R/include -DNDEBUG -fpic -O3 -pipe -g -c surfaceArea.c -o surfaceArea.o gcc -std=gnu99 -I/usr/share/R/include -DNDEBUG -fpic -O3 -pipe -g -c zerodist.c -o zerodist.o gcc -std=gnu99 -shared -o sp.so Rcentroid.o gcdist.o init.o pip.o pip2.o sp_xports.o surfaceArea.o zerodist.o -L/usr/lib/R/lib -lR installing to /home/checo/R/i486-pc-linux-gnu-library/2.15/sp/libs ** R ** data ** demo ** inst ** preparing package for lazy loading ** help *** installing help indices ** building package indices ** installing vignettes ‘intro_sp.Rnw’ ‘over.Rnw’ ** testing if installed package can be loaded * DONE (sp) * installing *source* package ‘rgeos’ ... ** package ‘rgeos’ successfully unpacked and MD5 sums checked configure: CC: gcc -std=gnu99 configure: CXX: g++ configure: rgeos: 0.2-17 checking for /usr/bin/svnversion... no configure: svn revision: 394 checking geos-config usability... ./configure: line 1385: geos-config: command not found no configure: error: geos-config not usable ERROR: configuration failed for package ‘rgeos’ * removing ‘/home/checo/R/i486-pc-linux-gnu-library/2.15/rgeos’ Warning in install.packages : installation of package ‘rgeos’ had non-zero exit status Forgive my ignorance, but I don't know where this file, "geos-config", comes from: should it be generated by the gcc compilations above, or should it be previously installed when the libgeos libraries were intalled? I learnt, from another machine, that "geos-config" is an executable and that it should be installed in /usr/bin. Do you have any idea on what's wrong with my procedure? Thanks, -Sergio.

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  • SQL Azure Security: DoS Part II

    - by Herve Roggero
    Ah!  When you shoot yourself in the foot... a few times... it hurts! That's what I did on Sunday, to learn more about the behavior of the SQL Azure Denial Of Service prevention feature. This article is a short follow up to my last post on this feature. In this post, I will outline some of the lessons learned that were the result of testing the behavior of SQL Azure from two machines. From the standpoint of SQL Azure, they look like one machine since they are behind a NAT. All logins affected The first thing to note is that all the logins are affected. If you lock yourself out to a specific database, none of the logins will work on that database. In fact the database size becomes "--" in the SQL Azure Portal.   Less than 100 sessions I was able to see 50+ sessions being made in SQL Azure (by looking at sys.dm_exec_sessions) before being locked out. The the DoS feature appears to be triggered in part by the number of open sessions. I could not determine if the lockout is triggered by the speed at which connection requests are made however.   Other Databases Unaffected This was interesting... the DoS feature works at the database level. Other databases were available for me to use.   Just Wait Initially I thought that going through SQL Azure and connecting from there would reset the database and allow me to connect again. Unfortunately this doesn't seem to be the case. You will have to wait. And the more you lock yourself out, the more you will have to wait... The first time the database became available again within 30 seconds or so; the second time within 2-3 minutes and the third time... within 2-3 hours...   Successful Logins The DoS feature appears to engage only for valid logins. If you have a login failure, it doesn't seem to count. I ran a test with over 100 login failures without being locked.

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  • WebLogic Partner Community Newsletter June 2012

    - by JuergenKress
    Dear WebLogic partner community member Happy New fiscal Year FY13 - thanks for the FY12 middleware business! Our WebLogic Partner Community grew very fast to 800+ members! To continue our joint successful business in the new fiscal year our top priorities in FY13 are: Become trained:the next opportunity are the summer camps in Lisbon & Munich or our on-demand training WebLogic 12c & ExaLogic & ADF see our detailed training calendar below. Run your marketing & sales campaign: sales kits, marketing kits, solution catalog add your services to oracle.com, add your events to oracle.com and advertisement Get recognized: OFM awards, partner excellence awards & references & plaques Become Specialized: All of the above makes the Oracle WebLogic 12c & ExaLogic & ADF Specialization! Make sure you get your Specialization benefits! Topics: Key product focus areas will be: ias to WebLogic & ExaLogic, ADF mobile and Oracle Java Cloud platform. Get a sneak preview of our FY13 sales plays (Oracle and Partner confidential) If you can not attend our Summer Camps and our WebLogic 12c Bootcamps please register for the on-demand Oracle WebLogic Server 12c Sales Boot Camp & Oracle WebLogic Server 12c PreSales Boot Camp and the WebLogic Server: Diagnosing Performance Webcast From June 1st 2012 ExaLogic Specialization is mandatory for re-sell! To support you with your opportunities we published the ExaLogic Kit & Cloud Application Foundation kit which includes sales ppt presentations and technical details! We are also highly interested to run a joint iAS to WebLogic upgrade marketing campaign! See you in Lisbon! Jürgen Kress Oracle WebLogic Partner Adoption EMEA To read the newsletter please visit http://tinyurl.com/WebLogicnewsJunea2012 (OPN Account required) To become a member of the WebLogic Partner Community please register at http://www.oracle.com/partners/goto/wls-emea ( OPN account required). If you need support with your account please contact the Oracle Partner Business Center. Blog Twitter LinkedIn Mix Forum Wiki Technorati Tags: WebLogic Community newsletter,WebLogic,WebLogic Community,OPN,Oracle,Jürgen Kress,WebLogic 12c,Fusion Middleware Innovation Awards 2012,SPCEjEnterprise 2012 Benchmark,WebLogic Benchmark Sun,Java training,WebLogic advisor webcast

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  • Maximizing the Value of Software

    - by David Dorf
    A few years ago we decided to increase our investments in documenting retail processes and architectures.  There were several goals but the main two were to help retailers maximize the value they derive from our software and help system integrators implement our software faster.  The sale is only part of our success metric -- its actually more important that the customer realize the benefits of the software.  That's when we actually celebrate. This week many of our customers are gathered in Chicago to discuss their successes during our annual Crosstalk conference.  That provides the perfect forum to announce the release of the Oracle Retail Reference Library.  The RRL is available for free to Oracle Retail customers and partners.  It contains 1000s of hours of work and represents years of experience in the retail industry.  The Retail Reference Library is composed of three offerings: Retail Reference Model We've been sharing the RRM for several years now, with lots of accolades.  The RRM is a set of business process diagrams at varying levels of granularity. This release marks the debut of Visio documents, which should make it easier for retailers to adopt and edit the diagrams.  The processes represent an approximation of the Oracle Retail software, but at higher levels they are pretty generic and therefore usable with other software as well.  Using these processes, the business and IT are better able to communicate the expectations of the software.  They can be used to guide customization when necessary, and help identify areas for optimization in the organization. Retail Reference Architecture When embarking on a software implementation project, it can be daunting to start from a blank sheet of paper.  So we offer the RRA, a comprehensive set of documents that describe the retail enterprise in terms of logical architecture, physical deployments, and systems integration.  These documents and diagrams describe how all the systems typically found in a retailer enterprise work together.  They serve as a way to jump-start implementations using best practices we've captured over the years. Retail Semantic Glossary Have you ever seen two people argue over something because they're using misaligned terminology?  Its a huge waste and happens all the time.  The Retail Semantic Glossary is a simple application that allows retailers to define terms and metrics in a centralized database.  This initial version comes with limited content with the goal of adding more over subsequent releases.  This is the single source for defining key performance indicators, metrics, algorithms, and terms so that the retail organization speaks in a consistent language. These three offerings are downloaded from MyOracleSupport separately and linked together using the start page above.  Everything is navigated using a Web browser.  See the Oracle Retail Documentation blog for more details.

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  • Resources to Help You Getting Up To Speed on ADF Mobile

    - by Joe Huang
    Hi, everyone: By now, I hope you would have a chance to review the sample applications and try to deploy it.  This is a great way to get started on learning ADF Mobile.  To help you getting started, here is a central list of "steps to get up to speed on ADF Mobile" and related resources that can help you developing your mobile application. Check out the ADF Mobile Landing Page on the Oracle Technology Network. View this introductory video. Read this Data Sheet and FAQ on ADF Mobile. JDeveloper 11.1.2.3 Download. Download the generic version of JDeveloper for installation on Mac. Note that there are workarounds required to install JDeveloper on a Mac. Download ADF Mobile Extension from JDeveloper Update Center or Here. Please note you will need to configure JDeveloper for Internet access (In HTTP Proxy preferences) in order the install the extension, as the installation process will prompt you for a license that's linked off Oracle's web site. View this end-to-end application creation video. View this end-to-end iOS deployment video if you are developing for iOS devices. Configure your development environment, including location of the SDK, etc in JDeveloper-Tools-Preferences-ADF Mobile dialog box.  The two videos above should cover some of these configuration steps. Check out the sample applications shipped with JDeveloper, and then deploy them to simulator/devices using the steps outlined in the video above.  This blog entry outlines all sample applications shipped with JDeveloper. Develop a simple mobile application by following this tutorial. Try out the Oracle Open World 2012 Hands on Lab to get a sense of how to programmatically access server data.  You will need these source files. Ask questions in the ADF/JDeveloper Forum. Search ADF Mobile Preview Forum for entries from ADF Mobile Beta Testing participants. For all other questions, check out this exhaustive and detailed ADF Mobile Developer Guide. If something does not seem right, check out the ADF Mobile Release Note. Thanks, Oracle ADF Mobile Product Management Team

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  • Common SOA Problems by C2B2

    - by JuergenKress
    SOA stands for Service Oriented Architecture and has only really come together as a concrete approach in the last 15 years or so, although the concepts involved have been around for longer. Oracle SOA Suite is based around the Service Component Architecture (SCA) devised by the Open SOA collaboration of companies including Oracle and IBM. SCA, as used in SOA suite, is designed as a way to crystallise the concepts of SOA into a standard which ensures that SOA principles like the separation of application and business logic are maintained. Orchestration or Integration? A common thing to see with many people who are beginning to either build a new SOA based infrastructure, or move an old system to be service oriented, is confusion in the purpose of SOA technologies like BPEL and enterprise service buses. For a lot of problems, orchestration tools like BPEL or integration tools like an ESB will both do the job and achieve the right objectives; however it’s important to remember that, although a hammer can be used to drive a screw into wood, that doesn’t mean it’s the best way to do it. Service Integration is the act of connecting components together at a low level, which usually results in a single external endpoint for you to expose to your customers or other teams within your organisation – a simple product ordering system, for example, might integrate a stock checking service and a payment processing service. Process Orchestration, however, is generally a higher level approach whereby the (often externally exposed) service endpoints are brought together to track an end-to-end business process. This might include the earlier example of a product ordering service and couple it with a business rules service and human task to handle edge-cases. A good (but not exhaustive) rule-of-thumb is that integrations performed by an ESB will usually be real-time, whereas process orchestration in a SOA composite might comprise processes which take a certain amount of time to complete, or have to wait pending manual intervention. BPEL vs BPMN For some, with pre-existing SOA or business process projects, this decision is effectively already made. For those embarking on new projects it’s certainly an important consideration for those using Oracle SOA software since, due to the components included in SOA Suite and BPM Suite, the choice of which to buy is determined by what they offer. Oracle SOA suite has no BPMN engine, whereas BPM suite has both a BPMN and a BPEL engine. SOA suite has the ESB component “Mediator”, whereas BPM suite has none. Decisions must be made, therefore, on whether just one or both process modelling languages are to be used. The wrong decision could be costly further down the line. Design for performance: Read the complete article here. SOA & BPM Partner Community For regular information on Oracle SOA Suite become a member in the SOA & BPM Partner Community for registration please visit www.oracle.com/goto/emea/soa (OPN account required) If you need support with your account please contact the Oracle Partner Business Center. Blog Twitter LinkedIn Facebook Wiki Technorati Tags: C2B2,SOA best practice,SOA Community,Oracle SOA,Oracle BPM,Community,OPN,Jürgen Kress

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  • Oracle GoldenGate 11gR2 Event Marker System

    - by Doug Reid
    0 false 18 pt 18 pt 0 0 false false false /* 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-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman"; mso-ascii-font-family:Cambria; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Cambria; mso-hansi-theme-font:minor-latin;} Oracle GoldenGate 11gR2 includes a number of refinements to the Event Marker system. Using event markers enables GoldenGate processes to take a defined action based on an event in the data stream. This feature within Oracle GoldenGate simplifies methods to embed specific custom processing in the areas of error handling, alerts, and notification. The event marker system effectively allows for DML driven workflows to be created within GoldenGate and enables customers to craft non-standard processing based on special events. There are a number of supported event actions including: trace, log, checkpoint before, suspend, abort, and several others. With 11gR1 events can now be triggered by DDL operations, plus variables can be passed in and out of the system to shell scripts. Some good use cases for this feature are Automatic switchover to the secondary system during planned outages Better monitoring over source systems’ performance and automated switchover to the standby system in case of an outage with the primary system Automatic switchover from initial load to changed data movement Automatic synchronization of any type of batch processing taking place on both the source and target databases for database consistency Automatic stoppage of the Delivery module to allow end-of-day reporting Finding, tracking, and reporting on transactions that are of interest including the ones that do not have primary keys or transaction record numbers If you would like to see a demo, please visit our youtube channel (http://youtube.com/oraclegoldengate)  To learn more about the new features of Oracle GoldenGate 11gR2 and to ask questions to the PM team, please join us on September 12th  8am or 10am PST for our live webcast. Click here to register.

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  • On the art of self-promotion

    - by Tony Davis
    I attended Brent Ozar's Building the Fastest SQL Servers session at Tech Ed last week, and found myself engulfed in a 'perfect storm' of excellent technical and presentational skills coupled with an astute awareness of the value of promoting one's work. I spend a lot of time at such events talking to developers and DBAs about the value of blogging and writing articles, and my impression is that some could benefit from a touch less modesty and a little more self-promotion. I sense a reticence in many would-be writers. Is what I have to say important enough? Haven't far more qualified and established commentators, MVPs and so on, already said it? While it's a good idea to pick reasonably fresh and interesting topics, it's more important not to let such fears lead to writer's block. In the eyes of any future employer, your published writing is an extension of your resume. They will not care that a certain MVP knows how to solve problem x, but they will be very interested to see that you have tackled that same problem, and solved it in your own way, and described the process in your own voice. In your current job, your writing is one of the ways you can express to your peers, and to the organization as a whole, the value of what you contribute. Many Developers and DBAs seem to rely on the idea that their work will speak for itself, and that their skill shines out from it. Unfortunately, this isn't always true. Many Development DBAs, for example, will be painfully aware of the massive effort involved in tuning and adding resilience to rapidly developed applications. However, others in the organization who are unaware of what's involved in getting an application that is 'done' ready for production may dismiss such efforts as fussiness or conservatism. At the dark end of the development cycle, chickens come home to roost, but their droppings tend to land on those trying to clear up the mess. My advice is this: next time you fix a bug or improve the resilience or performance of a database or application, make sure that you use team meetings, informal discussions and so on to ensure that people understand what the problem was and what you had to do to fix it. Use your blog to describe, generally, the process you adopted, the resources you used and the insights that came from your work. Encourage your colleagues to do the same. By spreading the art of self-promotion to everyone involved in an IT project, we get a better idea of the extent of the work and the value of the contribution of all the team members. As always, we'd love to hear what you think. This very week, Simple-talk launches its new blogging platform. If any of this has moved you to 'throw your hat into the ring', drop us a mail at [email protected]. Cheers, Tony.

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  • How do I take responsibility for my code when colleague makes unnecessary improvements without notice?

    - by Jesslyn
    One of my teammates is a jack of all trades in our IT shop and I respect his insight. However, sometimes he reviews my code (he's second in command to our team leader, so that's expected) without a heads up. So sometimes he reviews my changes before they complete the end goal and makes changes right away... and has even broken my work once. Other times, he has made unnecessary improvements to some of my code that is 3+ months old. This annoys me for a few reasons: I am not always given a chance to fix my mistakes He has not taken the time to ask me what I was trying to accomplish when he is confused, which could affect his testing or changes I don't always think his code is readable Deadlines are not an issue and his current workload doesn't require any work in my projects other than reviewing my code changes. Anyways, I have told him in the past to please keep me posted if he sees something in my work that he wants to change so that I could take ownership of my code (maybe I should have said "shortcomings") and he's not been responsive. I fear that I may come off as aggressive when I ask him to explain his changes to me. He's just a quiet person who keeps to himself, but his actions continue. I don't want to banish him from making code changes (not like I could), because we are a team--but I want to do my part to help our team. Added clarifications: We share 1 development branch. I do not wait until all my changes complete a single task because I risk losing some significant work--so I make sure my changes build and do not break anything. My concern is that my teammate doesn't explain the reason or purpose behind his changes. I don't think he should need my blessing, but if we disagree on an approach I thought it would be best to discuss the pros and cons and make a decision once we both understand what is going on. I have not discussed this with our team lead yet as I would prefer to resolve personal disagreements without getting management involved unless it is necessary. Since my concern seemed more of personal issue than a threat to our work, I chose to not bother the team lead. I am working on code review process ideas--to help promote the benefits of more organized code reviews without making it all about my pet peeves.

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  • NHibernate Session Load vs Get when using Table per Hierarchy. Always use ISession.Get&lt;T&gt; for TPH to work.

    - by Rohit Gupta
    Originally posted on: http://geekswithblogs.net/rgupta/archive/2014/06/01/nhibernate-session-load-vs-get-when-using-table-per-hierarchy.aspxNHibernate ISession has two methods on it : Load and Get. Load allows the entity to be loaded lazily, meaning the actual call to the database is made only when properties on the entity being loaded is first accessed. Additionally, if the entity has already been loaded into NHibernate Cache, then the entity is loaded directly from the cache instead of querying the underlying database. ISession.Get<T> instead makes the call to the database, every time it is invoked. With this background, it is obvious that we would prefer ISession.Load<T> over ISession.Get<T> most of the times for performance reasons to avoid making the expensive call to the database. let us consider the impact of using ISession.Load<T> when we are using the Table per Hierarchy implementation of NHibernate. Thus we have base class/ table Animal, there is a derived class named Snake with the Discriminator column being Type which in this case is “Snake”. If we load This Snake entity using the Repository for Animal, we would have a entity loaded, as shown below: public T GetByKey(object key, bool lazy = false) { if (lazy) return CurrentSession.Load<T>(key); return CurrentSession.Get<T>(key); } var tRepo = new NHibernateReadWriteRepository<TPHAnimal>(); var animal = tRepo.GetByKey(new Guid("602DAB56-D1BD-4ECC-B4BB-1C14BF87F47B"), true); var snake = animal as Snake; snake is null As you can see that the animal entity retrieved from the database cannot be cast to Snake even though the entity is actually a snake. The reason being ISession.Load prevents the entity to be cast to Snake and will throw the following exception: System.InvalidCastException :  Message=Unable to cast object of type 'TPHAnimalProxy' to type 'NHibernateChecker.Model.Snake'. Thus we can see that if we lazy load the entity using ISession.Load<TPHAnimal> then we get a TPHAnimalProxy and not a snake. =============================================================== However if do not lazy load the same cast works perfectly fine, this is since we are loading the entity from database and the entity being loaded is not a proxy. Thus the following code does not throw any exceptions, infact the snake variable is not null: var tRepo = new NHibernateReadWriteRepository<TPHAnimal>(); var animal = tRepo.GetByKey(new Guid("602DAB56-D1BD-4ECC-B4BB-1C14BF87F47B"), false); var snake = animal as Snake; if (snake == null) { var snake22 = (Snake) animal; }

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  • Training v. Teaching

    - by Chris Gardner
    Originally posted on: http://geekswithblogs.net/freestylecoding/archive/2014/05/28/training-v.-teaching.aspxAs some of you may know, I recently accepted a position to teach an undergraduate course at my alma mater. Yesterday, I had my first day in an academic classroom. I immediately noticed a difference with the interactions between the students. They don't act like students in a professional training or conference talk. I wanted to use this opportunity to enumerate some of those differences. The immediate thing I noticed was the lack of open environment. This is not to say the class was hostile towards me. I am used to entering the room, bantering with audience, loosening everyone a bit, and flowing into the discussion. A purely academic audience does not banter. At least, they do not banter on day one. I think I can attribute this to two factors. This first is a greater perception of authority. In a training or conference environment, I am an equal with the audience. This is true even if I am being a subject matter expert. We're all professionals. We're all there to learn from each other, share our stories, and enjoy the journey. In the academic classroom, there was a distinct class difference. I had forgotten about this distinction; I had the professional familiarity with the staff by the time I completed my masters. This leads to the other distinction. These was an expectation of performance. At conference and professional training, there is generally no (immediate) grading. This may be a preparation for a certification exam, but I'm not the one responsible for delivering the exam. This was not the case in the academic classroom. These students are battling for points, and I am the sole arbiter. These students are less likely to let the material wash over them, applying the material to their past experiences. They were down taking notes. I don't want to leave the impression that there was no interact in the classroom. I spent a good deal of time doing problems with the class on the whiteboard. I tried to get the class to help me work out the steps. This opened up a few of them. After every conference or training class, I always get a few people that will email me afterward to continue the conversation. I am very curious to see if anybody comes to my office hours tomorrow. However, that is a curiosity that will have to wait until tomorrow.

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  • Loading another domain's content in a modal iframe - acceptable?

    - by user568458
    Is it okay to load another page in an iframe in a modal pop-up window - in terms of legal and ethical standards around displaying 3rd party content? I remember a few years ago there was controversy and a debate about whether it was okay to load another domain's page content on your domain in a full-width iframe, with your site providing a masthead with controls for favouriting, linking etc (e.g. like StumbleUpon). I seem to recall that the consensus was, that it was okay so long as you were clearly in no way claiming ownership of the 3rd party content or attempting to modify the content and so long as there was a 'go to site' button or equivalent; and that sites could ask you to exclude them, but generally speaking, it's an acceptable practice. How acceptable would it be considered to be to load another site's page within a modal (lightbox-like) popup box (following all the above principles: clear attribution and a prominent button that kills the iframe and gives them the 3rd party original)? My expectation would be that it would follow the same principles, and be acceptable so long as these conditions were met. Note that I'm asking about the likely legitimate responses of the 3rd party sites and possible legal position, not about usability or UX. I'm aware that this should never ever ever ever ever be the standard way external links are loaded, and that 99% of the time linking to external content like this would be terrible for usability. My specific use case is one of those 1% of cases where loading a separate page in this tab actually wouldn't be the expected behaviour of a link: an interactive data visualisation tool that also acts as a 'browser' of external content (science papers underlying the data it navigates). All other links within the interactive will change something while staying on the same page. If the user clicked one of these external links by mistake (as people often do, even when they are clearly, noisily labelled) and then had to back-button back, they would lose their fine-grained position in the interactive tool (jquery bbq hashchanges being not appropriate for all elements of the tool). New window/tab will simply open the target page on the 3rd party domain. Opening a new window/tab would also be an alternative option (and has its own disadvantages) - my question is, whether this is an alternative that could be considered (in terms of acceptable practice around intellectual property etc), irrespective of which option is best for UX: which is something we'll decide the proper way, based on actual UX testing.

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  • My co-worker has not been doing such a good job for the past decade. What do I do? [closed]

    - by stijn
    Possible Duplicate: How do I approach a coworker about his or her code quality? I started working with him almost a decade ago and back then I had never really programmed before, being a young hardware engineer. Right now however I have made quite some progress in all areas being part of software design and i am much, much more skilled than my co-worker who is 15 years older and has been programming more than twice as long. He is super nice and definitely smart enough, but lately his lack of skill and performance are starting to drag me down because we're more and more working on the same codebase. And soon we are going to do a quite ambitious start from scratch creating a whole new hard/software system. I feel it is time to address all issues now, but i do not know how to start. Here are some of the things that I would like to see him improve on: no consistent usage of style, spaces nor tabs (eg if(something ) a =b ) adds newlines around pieces of code to make it easier to read, then commits those with messages like 'no changes made' overall commit messages are useless and so are most of the comments, if there are any (eg 'remove solves for bug Rik' if Rik reported a bug). There is no function/class documentation. lots of spelling errors, in both English and native language, which sometimes are mixed 6/7/8 level deep deep nesting is no exception, a lot of functions start with one level already like if(ptr!=Null){ even when ptr is the result of allocation via new in the constructor numerous source files have over 10k lines of those lines, a major part is simply a result of copy-pasting functionality instead of using a function. This includes copying comments so we end up with 50 occurrences of var=NULL; //TODO TEST this!!!!!!! another part is hundreds of lines of dead code knows what versioning does, yet comments out old code and places new code underneath it when making changes coding skills are below par, especially for the type of rather high precision applications we do. Yet somehow, after a lot of trying and testing, stuff starts to work. But then breaks again some time later because every change casues a waterfall effect. violates every single item in the C++ FAQ lite, practices every bad practice I can think of still doesn't know how to properly use the debugger, but spends hours inspecting messy logfiles in notepad on a tiny laptop screen. Does not make any adjustments to the settings of the software he uses. Never uses keyboard shortcuts. does not seem to progress or learn new things at all. Work rather slow, mostly due to the lack of planning and incorrect usage of tools. How does one deal with this? For starters, how do I make him aware of all these problems? Should I tell the staff about it? And the next step, how to get him to learn new things and adopt another way of working?

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  • Update in Certification Exam Score Report Access Process!

    - by Richard Lefebvre
    Please note that exam results for all Oracle Certification exams will be accessed through CertView, starting October 30th, 2012. Exam results will no longer be available at the test center, or on the Pearson VUE website. Candidates will receive an email from Oracle within 30 minutes of completing the exam to let them know that their exam results are available on CertView. Candidates must have an Oracle Web Account to access CertView. This new process applies to exam results for all Oracle Certification exams - proctored and non-proctored as well beta exams. CertView, Oracle's self-service certification portal will be the partners’ one stop source for all their certification and exam history! Other benefits of this change include: driving all candidates to have an Oracle Web Account which will lead to tighter integration with Oracle University records in the future, increased security around data privacy and a higher validity rate for candidate email addresses. Existing benefits of CertView include, self-service access to exam and certification records and logos, and access to Oracle's self service certification verification. Accessing Exam Results  Returning CertView Users ·         Click the link in the email sent by Oracle or go to certview.oracle.com ·         Select the See My New Exam Results Now link to view exam results ·         Select the Print My New Exam Results Now link to print exam results  New CertView Users - Who Have An Oracle Web Account ·         First time Users must authenticate their CertView account ·         Account Authentication requires the Oracle Testing ID and email address from your Pearson VUE profile ·         Click the link in the email sent by Oracle or go to certview.oracle.com and follow the Authenticate My CertView Account link.  New CertView Users - Who Do Not Have An Oracle Web Account ·         CertView users are required to have an Oracle Web Account ·         To create an Oracle Web Account, go to certview.oracle.com and select theCreate My Oracle Web Account Now link. Then follow the remaining instructions under I do not have an Oracle Web Account on that page.

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  • 12.04 Unity 3D 80% CPU load with Compiz

    - by user39288
    EDIT : I have been able to to determine that the problem is not compiz, but is actually Xorg. I don't know why, but by quickly maximizing terminal and taking a screenshot with top running before the problem went away I am able to see xorg takes up 72% of cpu, with bamfdaemon taking up 18%, and compiz taking up 14%. Seems the nvidia drivers are to blame, will play more with settings and perhaps do a clean nvidia-current install to try to fix the problem. Having a very annoying problem with high CPU usage. Running 12.04 with latest drivers and nvidia-current installed. Have not had any issues for days, now I have a strange problem. Unity 3d runs great most of the time, 1-2% CPU usage with only transmission running in background. Windows open and close smoothly. However,no matter what programs are open, if I minimize all open programs to the unity bar on the left, my CPU jumps to about 80% and slows down all maximize and minimize effects. Mouse movement stays smooth the whole time, but unity becomes unresponsive for up to 30 seconds at times. Hitting alt + tab to bring up even a single window fixes the problem. The window I bring back up doesn't even have to be maximized to solve the problem. Hitting the super button to bring up the dash makes CPU drop back to idle until I close it, then high CPU usage resumes. Believe the problem is compiz, but even just having only terminal running "top", I have to minimize it to the tray for the problem to show, so I can't see the problem process. I can only tell about the high CPU usage using indicator-sysmonitor. Even tried quitting the indicator, but I can still tell very poor performance with all applications when minimized. Reset compiz back to defaults, tried going to the post-release update nvidia drivers, played with vsync settings in both the nvidia settings and compiz. Even forced refresh rate, but cannot solve the problem. The problem does NOT occur in Unity 2D. Specs are core 2 duo 2.0ghz, 4GB ddr2 ram, 2x 320's HDD in RAID 0, and Nvidia GTX 260M graphics card.

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  • How are Reads Distributed in a Workload

    - by Bill Graziano
    People have uploaded nearly one millions rows of trace data to TraceTune.  That’s enough data to start to look at the results in aggregate.  The first thing I want to look at is logical reads.  This is the easiest metric to identify and fix. When you upload a trace, I rank each statement based on the total number of logical reads.  I also calculate each statement’s percentage of the total logical reads.  I do the same thing for CPU, duration and logical writes.  When you view a statement you can see all the details like this: This single statement consumed 61.4% of the total logical reads on the system while we were tracing it.  I also wanted to see the distribution of reads across statements.  That graph looks like this: On average, the highest ranked statement consumed just under 50% of the reads on the system.  When I tune a system, I’m usually starting in one of two modes: this “piece” is slow or the whole system is slow.  If a given piece (screen, report, query, etc.) is slow you can usually find the specific statements behind it and tune it.  You can make that individual piece faster but you may not affect the whole system. When you’re trying to speed up an entire server you need to identity those queries that are using the most disk resources in aggregate.  Fixing those will make them faster and it will leave more disk throughput for the rest of the queries. Here are some of the things I’ve learned querying this data: The highest ranked query averages just under 50% of the total reads on the system. The top 3 ranked queries average 73% of the total reads on the system. The top 10 ranked queries average 91% of the total reads on the system. Remember these are averages across all the traces that have been uploaded.  And I’m guessing that people mainly upload traces where there are performance problems so your mileage may vary. I also learned that slow queries aren’t the problem.  Before I wrote ClearTrace I used to identify queries by filtering on high logical reads using Profiler.  That picked out individual queries but those rarely ran often enough to put a large load on the system. If you look at the execution count by rank you’d see that the highest ranked queries also have the highest execution counts.  The graph would look very similar to the one above but flatter.  These queries don’t look that bad individually but run so often that they hog the disk capacity. The take away from all this is that you really should be tuning the top 10 queries if you want to make your system faster.  Tuning individually slow queries will help those specific queries but won’t have much impact on the system as a whole.

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  • Designing a completly new database/gui solution for my compnay

    - by user1277304
    I'm no expert when it come to Everything Visual Studio 2010 and utilizing SQL server 2008. I'm sure some of my personal projects I've built for personal use would get laughed off the face of the planet, but SQLCe has been the solution I was looking for those home type of projects. And they work, flawlessly. Now I feel it's time to step up to the big league. I want to develop a complete, unified and module based solution for my compnay that I'm working for. We're still using stuff from the 80s for goodness sake! I use Excel and query the ancient database on my own because I can't stand the GUI. Nothing against people of age, but the IDE our programmers are using is from the stone age, and they use APL of all things with it. I've yet to see a radio buttton control anywhere in the GUI where it would make sense. Anyway, I want to do this right from the ground up. I'm by no means a newbie when it comes to programming in .NET 2010, however, I want the entire solution to be professionaly done. I want version control, test projects, project flow, SQL 2008 integration and all the bells and whistles that come with that. I know for a fact that if we had something like that runnning, not only would development costs and time be slashed four fold, but the possibilities for expansion and performance would sky rocket. (Between the GUI an our DB engine, it can only use ONE CORE! ONE! It's 2012 for goodness sake!) Our buisness is growing and our current ancient solution just can't keep up, and I'd hate to see our buisness go down in flames because our programmer is stuck in the 80's and refuses to use anything current. So I ask you guys, the experts and know-it-alls, where do I start? Are there any gems of good books out there in the haystack of all "This for dummies" type of deals? I already have several people backing me in this endevour, and while it may seem brash to just usurp the current programmers, I'm doing this for the company as a whole. Thank you guys for your time.

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  • How granular should a command be in a CQ[R]S model?

    - by Aaronaught
    I'm considering a project to migrate part of our WCF-based SOA over to a service bus model (probably nServiceBus) and using some basic pub-sub to achieve Command-Query Separation. I'm not new to SOA, or even to service bus models, but I confess that until recently my concept of "separation" was limited to run-of-the-mill database mirroring and replication. Still, I'm attracted to the idea because it seems to provide all the benefits of an eventually-consistent system while sidestepping many of the obvious drawbacks (most notably the lack of proper transactional support). I've read a lot on the subject from Udi Dahan who is basically the guru on ESB architectures (at least in the Microsoft world), but one thing he says really puzzles me: As we get larger entities with more fields on them, we also get more actors working with those same entities, and the higher the likelihood that something will touch some attribute of them at any given time, increasing the number of concurrency conflicts. [...] A core element of CQRS is rethinking the design of the user interface to enable us to capture our users’ intent such that making a customer preferred is a different unit of work for the user than indicating that the customer has moved or that they’ve gotten married. Using an Excel-like UI for data changes doesn’t capture intent, as we saw above. -- Udi Dahan, Clarified CQRS From the perspective described in the quotation, it's hard to argue with that logic. But it seems to go against the grain with respect to SOAs. An SOA (and really services in general) are supposed to deal with coarse-grained messages so as to minimize network chatter - among many other benefits. I realize that network chatter is less of an issue when you've got highly-distributed systems with good message queuing and none of the baggage of RPC, but it doesn't seem wise to dismiss the issue entirely. Udi almost seems to be saying that every attribute change (i.e. field update) ought to be its own command, which is hard to imagine in the context of one user potentially updating hundreds or thousands of combined entities and attributes as it often is with a traditional web service. One batch update in SQL Server may take a fraction of a second given a good highly-parameterized query, table-valued parameter or bulk insert to a staging table; processing all of these updates one at a time is slow, slow, slow, and OLTP database hardware is the most expensive of all to scale up/out. Is there some way to reconcile these competing concerns? Am I thinking about it the wrong way? Does this problem have a well-known solution in the CQS/ESB world? If not, then how does one decide what the "right level" of granularity in a Command should be? Is there some "standard" one can use as a starting point - sort of like 3NF in databases - and only deviate when careful profiling suggests a potentially significant performance benefit? Or is this possibly one of those things that, despite several strong opinions being expressed by various experts, is really just a matter of opinion?

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  • Block-level deduplicating filesystem

    - by James Haigh
    I'm looking for a deduplicating copy-on-write filesystem solution for general user data such as /home and backups of it. It should use online/inline/synchronous deduplication at the block-level using secure hashing (for negligible chance of collisions) such as SHA256 or TTH. Duplicate blocks need not even touch the disk. The idea is that I should be able to just copy /home/<user> to an external HDD with the same such filesystem to do a backup. Simple. No messing around with incremental backups where corruption to any of the snapshots will nearly always break all later snapshots, and no need to use a specific tool to delete or 'checkout' a snapshot. Everything should simply be done from the file browser without worry. Can you imagine how easy this would be? I'd never have to think twice about backing-up again! I don't mind a performance hit, reliability is the main concern. Although, with specific implementations of cp, mv and scp, and a file browser plugin, these operations would be very fast, especially when there is a lot of duplication as they would only need to transfer the absent blocks. Accidentally using conventional copy tools that do not integrate with the FS would merely take longer, waste some bandwidth when copying remotely and waste some CPU, as the duplicate data would be re-read, re-transferred and re-hashed (although nothing would be re-written), but would absolutely not corrupt anything. (Some filesharing software may also be able to benefit by integrating with the FS.) So what's the best way of doing this? I've looked at some options: lessfs - Looks unmaintained. Any good? [Opendedup/SDFS][3] - Java? Could I use this on Android?! What does [SDFS][4] stand for? [Btrfs][5] - Some patches floating around on mailing list archives, but no real support. [ZFS][6] - Hopefully they'll one day relicense under a true Free/Opensource GPL-compatible licence. Also, 2 years ago I had a go at an attempt in Python using Fuse at the file-level to be used over the top of a typical solid FS such as EXT4, but I found Fuse for Python underdocumented and didn't manage to implement all of the system calls. My first post here, so I can't post more than 2 links until I get over 10 rep: [3]: http://www.opendedup.org/ [4]: https://en.wikipedia.org/w/index.php?title=SDFS&action=edit&redlink=1 [5]: https://en.wikipedia.org/wiki/Btrfs#Features [6]: https://en.wikipedia.org/wiki/ZFS#Linux

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  • Setting MTU on Exalogic

    - by csoto
    For many reasons, a system administrator may want to change the MTU settings of a server. But in a system like Exalogic which contains lots of interconnected nodes and other various components, it's important to understand how this applies to the different networks. For example, when bringing up bonding of InfiniBand an error like the following may be thrown: Bringing up interface bond1: SIOCSIFMTU: Invalid argument Both scripts ifcfg-ib0 and ifcfg-ib1 (from the /etc/sysconfig/network-scripts/ direectory) have MTU set to 65500, which is a valid MTU value only if all IPoIB slaves operate in connected mode and are configured with the same value, so the line below must be added to both network scripts and then restart the network: CONNECTED_MODE=yes By the way, an error of the form “SIOCSIFMTU: Invalid argument” indicates that the requested MTU was rejected by the kernel. Typically this would be due to it exceeding the maximum value supported by the interface hardware. In that case you must either reduce the MTU to a value that is supported or obtain more capable hardware. This problem has been seen when trying to modify the MTU using the ifconfig command, like the output of the example below: [root@elxxcnxx ~]# ifconfig ib1 mtu 65520 SIOCSIFMTU: Invalid argument It's important to insist that in most cases the nodes must be rebooted after the MTU size has been changed. Although in some circumstances it may work without a reboot, it is not how it is typically documented. Now, in order to achieve a reduced memory consumption and improve performance for network traffic received on IPoIB related interfaces, it is recommend to reduce the MTU value in interface configuration files for IPoIB related bonds from 65520 to 64000. The change needs to be made to interface configuration files under the /etc/sysconfig/network-scripts directory and applies to the interface configuration files for bonds over IPoIB related slave devices, for example /etc/sysconfig/network-scripts/ifcfg-bond1. However, keep in mind that the numeric portion of the interface filenames that corresponding to IPoIB interfaces is expected to vary across compute nodes and vServers and so cannot be relied upon to identify which interface files are for bonds are over IPoIB rather than EoIB related slave interfaces. To fix these MTU values to the recommended settings, there are very useful instructions and a script on the MOS Note 1624434.1, and it's applicable physical and virtual configurations of Exalogic. Regarding the recommended MTU value for EoIB related interfaces, its maximum appropriate value is 1500. If for some reason a vServer has been created with a higher value (set on the /etc/sysconfig/network-scripts/ifcfg-bond0 file), then it must be fixed. An error like the following could be thrown under this circumstance: [root@vServer ~]# service network restart ... Bringing up interface bond0:  SIOCSIFMTU: Invalid argument Also an error like the one below can be seen on the /var/log/messages file of the vServer: kernel: T5074835532 [mlx4_vnic] eth1:vnic_change_mtu:360: failed: new_mtu 64000 2026 The MOS Note 1611657.1 is very useful for this purpose.

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