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• Packaging Swing apps with integrated JavaFX content

  - by igor

  JavaFX provides a lot of interesting capabilities for developing rich client applications in Java, but what if you are working on an existing Swing application and you want to take advantage of these new features?  Maybe you want to use one or two controls like the LineChart or a MediaView.  Maybe you want to embed a large Scene Graph as an initial step in porting your application to FX.  A hybrid Swing/FX application might just be the answer. Developing a hybrid Swing + JavaFX application is not terribly difficult, but until recently the deployment of hybrid applications has not simple as a "pure" JavaFX application.  The existing tools focused on packaging FX Applications, or Swing applications - they did not account for hybrid applications. But with JavaFX 2.2 the tools include support for this hybrid application use case.  Solution  In JavaFX 2.2 we extended the packaging ant tasks to greatly simplify deploying hybrid applications.  You now use the same deployment approach as you would for pure JavaFX applications.  Just bundle your main application jar with the fx:jar ant task and then generate html/jnlp files using fx:deploy.  The only difference is setting toolkit attribute for the fx:application tag as shown below: <fx:application id="swingFXApp" mainClass="${main.class}" toolkit="swing"/>  The value of ${main.class} in the example above is your application class which has a main method.  It does not need to extend JavaFX Application class. The resulting package provides support for the same set of execution modes as a package for a JavaFX application, although the packages which are created are not identical to the packages created for a pure FX application.  You will see two JNLP files generated in the case of a hybrid application - one for use from Swing applet and another for the webstart launch.  Note that these improvements do not alter the set of features available to Swing applications. The packaging tools just make it easier to use the advanced features of JavaFX in your Swing application. The same limits still apply, for example a Swing application can not use JavaFX Preloaders and code changes are necessary to support HTML splash screens. Why should I use the JavaFX ant tasks for packaging my Swing application?  While using FX packaging tool for a Swing application may seem like a mismatch at face value, there are some really good reasons to use this approach.  The primary justification for our packaging tools is to simplify the creation of your application artifacts, and to reduce manual errors.  Plus, no one should have to write JNLP by hand. Some specific benefits include: Your application jar will include a launcher program.  This improves your standalone launch by: checking for the JavaFX runtime guiding the user through any necessary installations setting the system proxy for Java The ant tasks will generate JNLP and HTML files for your swing app: avoids learning unnecessary details about JNLP, and eliminates the error-prone hand editing of JNLP files simplifies using advanced features like embedding JNLP and signing jars as BLOBs to improve launch performance.you can also embed the signing certificate details to improve the user's experience  allows the use of web page templates to inject the generated code directly into your actual web page instead of being forced to copy/paste the generated code snippets. What about native packing? Absolutely!  The very same ant task can generate a native bundle for a Swing application with JavaFX content.  Try running one of these sample native bundles for the "SwingInterop" FX example: exe and dmg.   I also used another feature on these examples: a click-through license agreement for .exe installers and OS X DMG drag installers. Small Caveat This packaging procedure is optimized around using the JavaFX packaging tools for your entire Swing application.  If you are trying to embed JavaFX content into existing project (with an existing build/packing process) then you may need to experiment in order to find the best way to integrate the JavaFX packaging steps into your existing build procedure. As long as you can use ant in your build process this should be a workable approach. It some cases solution could be less than ideal. For example, you need to use fx:jar to package your main jar file in order to produce a double-clickable jar or a native bundle.  The jar will be created from scratch, but you may already be creating the main jar file with a custom manifest.  This may lead to some redundant steps in your build process.  Hopefully the benefits will outweigh the problems. This is an area of ongoing development for the team, and we will continue to refine and improve both the tools and the process. Please share your experiences and suggestions with us.  You can comment here on the blog or file issues to JIRA. Sample code Here is the full ant code used to package SwingInterop.  You can grab latest JavaFX samples and try it yourself:  <target name="-post-jar"> <taskdef resource="com/sun/javafx/tools/ant/antlib.xml" uri="javafx:com.sun.javafx.tools.ant" classpath="${javafx.tools.ant.jar}"/> <!-- Mark application as Swing-based --> <fx:application id="swingFXApp" mainClass="${main.class}" toolkit="swing"/> <!-- Create doubleclickable jar file with embedded launcher --> <fx:jar destfile="${dist.jar}"> <fileset dir="${build.classes.dir}"/> <fx:application refid="swingFXApp" name="SwingInterop"/> <manifest> <attribute name="Implementation-Vendor" value="${application.vendor}"/> <attribute name="Implementation-Title" value="${application.title}"/> <attribute name="Implementation-Version" value="1.0"/> </manifest> </fx:jar> <!-- sign application jar. Use new self signed certificate --> <delete file="${build.dir}/test.keystore"/> <genkey alias="TestAlias" storepass="xyz123" keystore="${build.dir}/test.keystore" dname="CN=Samples, OU=JavaFX Dev, O=Oracle, C=US"/> <fx:signjar keystore="${build.dir}/test.keystore" alias="TestAlias" storepass="xyz123"> <fileset file="${dist.jar}"/> </fx:signjar> <!-- generate JNLPs, HTML and native bundles --> <fx:deploy width="960" height="720" includeDT="true" nativeBundles="all" outdir="${basedir}/${dist.dir}" embedJNLP="true" outfile="${application.title}"> <fx:application refId="swingFXApp"/> <fx:resources> <fx:fileset dir="${basedir}/${dist.dir}" includes="SwingInterop.jar"/> </fx:resources> <fx:permissions/> <info title="Sample app: ${application.title}" vendor="${application.vendor}"/> </fx:deploy> </target>

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• Online Password Security Tactics

  - by BuckWoody

  Recently two more large databases were attacked and compromised, one at the popular Gawker Media sites and the other at McDonald’s. Every time this kind of thing happens (which is FAR too often) it should remind the technical professional to ensure that they secure their systems correctly. If you write software that stores passwords, it should be heavily encrypted, and not human-readable in any storage. I advocate a different store for the login and password, so that if one is compromised, the other is not. I also advocate that you set a bit flag when a user changes their password, and send out a reminder to change passwords if that bit isn’t changed every three or six months.    But this post is about the *other* side – what to do to secure your own passwords, especially those you use online, either in a cloud service or at a provider. While you’re not in control of these breaches, there are some things you can do to help protect yourself. Most of these are obvious, but they contain a few little twists that make the process easier.   Use Complex Passwords This is easily stated, and probably one of the most un-heeded piece of advice. There are three main concepts here: ·         Don’t use a dictionary-based word ·         Use mixed case ·         Use punctuation, special characters and so on   So this: password Isn’t nearly as safe as this: P@ssw03d   Of course, this only helps if the site that stores your password encrypts it. Gawker does, so theoretically if you had the second password you’re in better shape, at least, than the first. Dictionary words are quickly broken, regardless of the encryption, so the more unusual characters you use, and the farther away from the dictionary words you get, the better.   Of course, this doesn’t help, not even a little, if the site stores the passwords in clear text, or the key to their encryption is broken. In that case…   Use a Different Password at Every Site What? I have hundreds of sites! Are you kidding me? Nope – I’m not. If you use the same password at every site, when a site gets attacked, the attacker will store your name and password value for attacks at other sites. So the only safe thing to do is to use different names or passwords (or both) at each site. Of course, most sites use your e-mail as a username, so you’re kind of hosed there. So even though you have hundreds of sites you visit, you need to have at least a different password at each site.   But it’s easier than you think – if you use an algorithm.   What I’m describing is to pick a “root” password, and then modify that based on the site or purpose. That way, if the site is compromised, you can still use that root password for the other sites.   Let’s take that second password: P@ssw03d   And now you can append, prepend or intersperse that password with other characters to make it unique to the site. That way you can easily remember the root password, but make it unique to the site. For instance, perhaps you read a lot of information on Gawker – how about these:   P@ssw03dRead ReadP@ssw03d PR@esasdw03d   If you have lots of sites, tracking even this can be difficult, so I recommend you use password software such as Password Safe or some other tool to have a secure database of your passwords at each site. DO NOT store this on the web. DO NOT use an Office document (Microsoft or otherwise) that is “encrypted” – the encryption office automation packages use is very trivial, and easily broken. A quick web search for tools to do that should show you how bad a choice this is.   Change Your Password on a Schedule I know. It’s a real pain. And it doesn’t seem worth it…until your account gets hacked. A quick note here – whenever a site gets hacked (and I find out about it) I change the password at that site immediately (or quit doing business with them) and then change the root password on every site, as quickly as I can.   If you follow the tip above, it’s not as hard. Just add another number, year, month, day, something like that into the mix. It’s not unlike making a Primary Key in an RDBMS.   P@ssw03dRead10242010   Change the site, and then update your password database. I do this about once a month, on the first or last day, during staff meetings. (J)   If you have other tips, post them here. We can all learn from each other on this.

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• Becoming A Great Developer

  - by Lee Brandt

  Image via Wikipedia I’ve been doing the whole programming thing for awhile and reading and watching some of the best in the business. I have come to notice that the really great developers do a few things that (I think) makes them great. Now don’t get me wrong, I am not saying that I am one of these few. I still struggle with doing some of the things that makes one great at development. Coincidently, many of these things also make you a better person period. Believe That Guidance Is Better Than Answers This is one I have no problem with. I prefer guidance any time I am learning from another developer. Answers may get you going, but guidance will leave you stranded. At some point, you will come across a problem that can only be solved by thinking for yourself and this is where that guidance will really come in handy. You can use that guidance and extrapolate whatever technology to salve that problem (if it’s the right tool for solving that problem). The problem is, lots of developers simply want someone to tell them, “Do this, then this, then set that, and write this.” Favor thinking and learn the guidance of doing X and don’t ask someone to show you how to do X, if that makes sense. Read, Read and Read If you don’t like reading, you’re probably NOT going to make it into the Great Developer group. Great developers read books, they read magazines and they read code. Open source playgrounds like SourceForge, CodePlex and GitHub, have made it extremely easy to download code from developers you admire and see how they do stuff. Chances are, if you read their blog too, they’ll even explain WHY they did what they did (see “Guidance” above). MSDN and Code Magazine have not only code samples, but explanations of how to use certain technologies and sometimes even when NOT to use that same technology. Books are also out on just about every topic. I still favor the less technology centric books. For instance, I generally don’t buy books like, “Getting Started with Jiminy Jappets”. I look for titles like, “How To Write More Effective Code” (again, see guidance). The Addison-Wesley Signature Series is a great example of these types of books. They teach technology-agnostic concepts. Head First Design Patterns is another great guidance book. It teaches the "Gang Of Four" Design Patterns in a very easy-to-understand, picture-heavy way (I LIKE pictures). Hang Your Balls Out There Even though the advice came from a 3rd-shift Kinko’s attendant, doesn’t mean it’s not sound advice. Write some code and put it out for others to read, criticize and castigate you for. Understand that there are some real jerks out there who are absolute geniuses. Don’t be afraid to get some great advice wrapped in some really nasty language. Try to take what’s good about it and leave what’s not. I have a tough time with this myself. I don’t really have any code out there that is available for review (other than my demo code). It takes some guts to do, but in the end, there is no substitute for getting a community of developers to critique your code and give you ways to improve. Get Involved Speaking of community, the local and online user groups and discussion forums are a great place to hear about technologies and techniques you might never come across otherwise. Mostly because you might not know to look. But, once you sit down with a bunch of other developers and start discussing what you’re interested in, you may open up a whole new perspective on it. Don’t just go to the UG meetings and watch the presentations either, get out there and talk, socialize. I realize geeks weren’t meant to necessarily be social creatures, but if you’re amongst other geeks, it’s much easier. I’ve learned more in the last 3-4 years that I have been involved in the community that I did in my previous 8 years of coding without it. Socializing works, even if socialism doesn’t. Continuous Improvement Lean proponents might call this “Kaizen”, but I call it progress. We all know, especially in the technology realm, if you’re not moving ahead, you’re falling behind. It may seem like drinking from a fire hose, but step back and pick out the technologies that speak to you. The ones that may you’re little heart go pitter-patter. Concentrate on those. If you’re still overloaded, pick the best of the best. Just know that if you’re not looking at the code you wrote last week or at least last year with some embarrassment, you’re probably stagnating. That’s about all I can say about that, cause I am all out of clichés to throw at it. :0) Write Code Great painters paint, great writers write, and great developers write code. The most sure-fire way to improve your coding ability is to continue writing code. Don’t just write code that your work throws on you, pick that technology you love or are curious to know more about and walk through some blog demo examples. Take the language you use everyday and try to get it to do something crazy. Who knows, you might create the next Google search algorithm! All in all, being a great developer is about finding yourself in all this code. If it is just a job to you, you will probably never be one of the “Great Developers”, but you’re probably okay with that. If, on the other hand, you do aspire to greatness, get out there and GET it. No one’s going hand it to you.

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• College Courses through distance learning

  - by Matt

  I realize this isn't really a programming question, but didn't really know where to post this in the stackexchange and because I am a computer science major i thought id ask here. This is pretty unique to the programmer community since my degree is about 95% programming. I have 1 semester left, but i work full time. I would like to finish up in December, but to make things easier i like to take online classes whenever I can. So, my question is does anyone know of any colleges that offer distance learning courses for computer science? I have been searching around and found a few potential classes, but not sure yet. I would like to gather some classes and see what i can get approval for. Class I need: Only need one C SC 437 Geometric Algorithms C SC 445 Algorithms C SC 473 Automata Only need one C SC 452 Operating Systems C SC 453 Compilers/Systems Software While i only need of each of the above courses i still need to take two more electives. These also have to be upper 400 level classes. So i can take multiple in each category. Some other classes I can take are: CSC 447 - Green Computing CSC 425 - Computer Networking CSC 460 - Database Design CSC 466 - Computer Security I hoping to take one or two of these courses over the summer. If not, then online over the regular semester would be ok too. Any help in helping find these classes would be awesome. Maybe you went to a college that offered distance learning. Some of these classes may be considered to be graduate courses too. Descriptions are listed below if you need. Thanks! Descriptions Computer Security This is an introductory course covering the fundamentals of computer security. In particular, the course will cover basic concepts of computer security such as threat models and security policies, and will show how these concepts apply to specific areas such as communication security, software security, operating systems security, network security, web security, and hardware-based security. Computer Networking Theory and practice of computer networks, emphasizing the principles underlying the design of network software and the role of the communications system in distributed computing. Topics include routing, flow and congestion control, end-to-end protocols, and multicast. Database Design Functions of a database system. Data modeling and logical database design. Query languages and query optimization. Efficient data storage and access. Database access through standalone and web applications. Green Computing This course covers fundamental principles of energy management faced by designers of hardware, operating systems, and data centers. We will explore basic energy management option in individual components such as CPUs, network interfaces, hard drives, memory. We will further present the energy management policies at the operating system level that consider performance vs. energy saving tradeoffs. Finally we will consider large scale data centers where energy management is done at multiple layers from individual components in the system to shutting down entries subset of machines. We will also discuss energy generation and delivery and well as cooling issues in large data centers. Compilers/Systems Software Basic concepts of compilation and related systems software. Topics include lexical analysis, parsing, semantic analysis, code generation; assemblers, loaders, linkers; debuggers. Operating Systems Concepts of modern operating systems; concurrent processes; process synchronization and communication; resource allocation; kernels; deadlock; memory management; file systems. Algorithms Introduction to the design and analysis of algorithms: basic analysis techniques (asymptotics, sums, recurrences); basic design techniques (divide and conquer, dynamic programming, greedy, amortization); acquiring an algorithm repertoire (sorting, median finding, strong components, spanning trees, shortest paths, maximum flow, string matching); and handling intractability (approximation algorithms, branch and bound). Automata Introduction to models of computation (finite automata, pushdown automata, Turing machines), representations of languages (regular expressions, context-free grammars), and the basic hierarchy of languages (regular, context-free, decidable, and undecidable languages). Geometric Algorithms The study of algorithms for geometric objects, using a computational geometry approach, with an emphasis on applications for graphics, VLSI, GIS, robotics, and sensor networks. Topics may include the representation and overlaying of maps, finding nearest neighbors, solving linear programming problems, and searching geometric databases.

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• Profiling Startup Of VS2012 &ndash; SpeedTrace Profiler

  - by Alois Kraus

  SpeedTrace is a relatively unknown profiler made a company called Ipcas. A single professional license does cost 449€+VAT. For the test I did use SpeedTrace 4.5 which is currently Beta. Although it is cheaper than dotTrace it has by far the most options to influence how profiling does work. First you need to create a tracing project which does configure tracing for one process type. You can start the application directly from the profiler or (much more interesting) it does attach to a specific process when it is started. For this you need to check “Trace the specified …” radio button and enter the process name in the “Process Name of the Trace” edit box. You can even selectively enable tracing for processes with a specific command line. Then you need to activate the trace project by pressing the Activate Project button and you are ready to start VS as usual. If you want to profile the next 10 VS instances that you start you can set the Number of Processes counter to e.g. 10. This is immensely helpful if you are trying to profile only the next 5 started processes. As you can see there are many more tabs which do allow to influence tracing in a much more sophisticated way. SpeedTrace is the only profiler which does not rely entirely on the profiling Api of .NET. Instead it does modify the IL code (instrumentation on the fly) to write tracing information to disc which can later be analyzed. This approach is not only very fast but it does give you unprecedented analysis capabilities. Once the traces are collected they do show up in your workspace where you can open the trace viewer. I do skip the other windows because this view is by far the most useful one. You can sort the methods not only by Wall Clock time but also by CPU consumption and wait time which none of the other products support in their views at the same time. If you want to optimize for CPU consumption sort by CPU time. If you want to find out where most time is spent you need Clock Total time and Clock Waiting. There you can directly see if the method did take long because it did wait on something or it did really execute stuff that did take so long. Once you have found a method you want to drill deeper you can double click on a method to get to the Caller/Callee view which is similar to the JetBrains Method Grid view. But this time you do see much more. In the middle is the clicked method. Above are the methods that call you and below are the methods that you do directly call. Normally you would then start digging deeper to find the end of the chain where the slow method worth optimizing is located. But there is a shortcut. You can press the magic   button to calculate the aggregation of all called methods. This is displayed in the lower left window where you can see each method call and how long it did take. There you can also sort to see if this call stack does only contain methods (e.g. WCF connect calls which you cannot make faster) not worth optimizing. YourKit has a similar feature where it is called Callees List. In the Functions tab you have in the context menu also many other useful analysis options One really outstanding feature is the View Call History Drilldown. When you select this one you get not a sum of all method invocations but a list with the duration of each method call. This is not surprising since SpeedTrace does use tracing to get its timings. There you can get many useful graphs how this method did behave over time. Did it become slower at some point in time or was only the first call slow? The diagrams and the list will tell you that. That is all fine but what should I do when one method call was slow? I want to see from where it was coming from. No problem select the method in the list hit F10 and you get the call stack. This is a life saver if you e.g. search for serialization problems. Today Serializers are used everywhere. You want to find out from where the 5s XmlSerializer.Deserialize call did come from? Hit F10 and you get the call stack which did invoke the 5s Deserialize call. The CPU timeline tab is also useful to find out where long pauses or excessive CPU consumption did happen. Click in the graph to get the Thread Stacks window where you can get a quick overview what all threads were doing at this time. This does look like the Stack Traces feature in YourKit. Only this time you get the last called method first which helps to quickly see what all threads were executing at this moment. YourKit does generate a rather long list which can be hard to go through when you have many threads. The thread list in the middle does not give you call stacks or anything like that but you see which methods were found most often executing code by the profiler which is a good indication for methods consuming most CPU time. This does sound too good to be true? I have not told you the best part yet. The best thing about this profiler is the staff behind it. When I do see a crash or some other odd behavior I send a mail to Ipcas and I do get usually the next day a mail that the problem has been fixed and a download link to the new version. The guys at Ipcas are even so helpful to log in to your machine via a Citrix Client to help you to get started profiling your actual application you want to profile. After a 2h telco I was converted from a hater to a believer of this tool. The fast response time might also have something to do with the fact that they are actively working on 4.5 to get out of the door. But still the support is by far the best I have encountered so far. The only downside is that you should instrument your assemblies including the .NET Framework to get most accurate numbers. You can profile without doing it but then you will see very high JIT times in your process which can severely affect the correctness of the measured timings. If you do not care about exact numbers you can also enable in the main UI in the Data Trace tab logging of method arguments of primitive types. If you need to know what files at which times were opened by your application you can find it out without a debugger. Since SpeedTrace does read huge trace files in its reader you should perhaps use a 64 bit machine to be able to analyze bigger traces as well. The memory consumption of the trace reader is too high for my taste. But they did promise for the next version to come up with something much improved.

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• InnoDB Compression Improvements in MySQL 5.6

  - by Inaam Rana

  MySQL 5.6 comes with significant improvements for the compression support inside InnoDB. The enhancements that we'll talk about in this piece are also a good example of community contributions. The work on these was conceived, implemented and contributed by the engineers at Facebook. Before we plunge into the details let us familiarize ourselves with some of the key concepts surrounding InnoDB compression. In InnoDB compressed pages are fixed size. Supported sizes are 1, 2, 4, 8 and 16K. The compressed page size is specified at table creation time. InnoDB uses zlib for compression. InnoDB buffer pool will attempt to cache compressed pages like normal pages. However, whenever a page is actively used by a transaction, we'll always have the uncompressed version of the page as well i.e.: we can have a page in the buffer pool in compressed only form or in a state where we have both the compressed page and uncompressed version but we'll never have a page in uncompressed only form. On-disk we'll always only have the compressed page. When both compressed and uncompressed images are present in the buffer pool they are always kept in sync i.e.: changes are applied to both atomically. Recompression happens when changes are made to the compressed data. In order to minimize recompressions InnoDB maintains a modification log within a compressed page. This is the extra space available in the page after compression and it is used to log modifications to the compressed data thus avoiding recompressions. DELETE (and ROLLBACK of DELETE) and purge can be performed without recompressing the page. This is because the delete-mark bit and the system fields DB_TRX_ID and DB_ROLL_PTR are stored in uncompressed format on the compressed page. A record can be purged by shuffling entries in the compressed page directory. This can also be useful for updates of indexed columns, because UPDATE of a key is mapped to INSERT+DELETE+purge. A compression failure happens when we attempt to recompress a page and it does not fit in the fixed size. In such case, we first try to reorganize the page and attempt to recompress and if that fails as well then we split the page into two and recompress both pages. Now lets talk about the three major improvements that we made in MySQL 5.6.Logging of Compressed Page Images:InnoDB used to log entire compressed data on the page to the redo logs when recompression happens. This was an extra safety measure to guard against the rare case where an attempt is made to do recovery using a different zlib version from the one that was used before the crash. Because recovery is a page level operation in InnoDB we have to be sure that all recompress attempts must succeed without causing a btree page split. However, writing entire compressed data images to the redo log files not only makes the operation heavy duty but can also adversely affect flushing activity. This happens because redo space is used in a circular fashion and when we generate much more than normal redo we fill up the space much more quickly and in order to reuse the redo space we have to flush the corresponding dirty pages from the buffer pool.Starting with MySQL 5.6 a new global configuration parameter innodb_log_compressed_pages. The default value is true which is same as the current behavior. If you are sure that you are not going to attempt to recover from a crash using a different version of zlib then you should set this parameter to false. This is a dynamic parameter.Compression Level:You can now set the compression level that zlib should choose to compress the data. The global parameter is innodb_compression_level - the default value is 6 (the zlib default) and allowed values are 1 to 9. Again the parameter is dynamic i.e.: you can change it on the fly.Dynamic Padding to Reduce Compression Failures:Compression failures are expensive in terms of CPU. We go through the hoops of recompress, failure, reorganize, recompress, failure and finally page split. At the same time, how often we encounter compression failure depends largely on the compressibility of the data. In MySQL 5.6, courtesy of Facebook engineers, we have an adaptive algorithm based on per-index statistics that we gather about compression operations. The idea is that if a certain index/table is experiencing too many compression failures then we should try to pack the 16K uncompressed version of the page less densely i.e.: we let some space in the 16K page go unused in an attempt that the recompression won't end up in a failure. In other words, we dynamically keep adding 'pad' to the 16K page till we get compression failures within an agreeable range. It works the other way as well, that is we'll keep removing the pad if failure rate is fairly low. To tune the padding effort two configuration variables are exposed. innodb_compression_failure_threshold_pct: default 5, range 0 - 100,dynamic, implies the percentage of compress ops to fail before we start using to padding. Value 0 has a special meaning of disabling the padding. innodb_compression_pad_pct_max: default 50, range 0 - 75, dynamic, the  maximum percentage of uncompressed data page that can be reserved as pad.

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• My Red Gate Experience

  - by Colin Rothwell

  I’m Colin, and I’ve been an intern working with Mike in publishing on Simple-Talk and SQLServerCentral for the past ten weeks. I’ve mostly been working “behind the scenes”, making improvements to the spam filtering, along with various other small tweaks. When I arrived at Red Gate, one of the first things Mike asked me was what I wanted to get out of the internship. It wasn’t a question I’d given a great deal of thought to, but my immediate response was the same as almost anybody: to support my growing family. Well, ok, not quite that, but money was certainly a motivator, along with simply making sure that I didn’t get bored over the summer. Three months is a long time to fill, and many of my friends end up getting bored, or worse, knitting obsessively. With the arrogance which seems fairly common among Cambridge people, I wasn’t expecting to really learn much here! In my mind, the part of the year where I am at Uni is the part where I learn things, whilst Red Gate would be an opportunity to apply what I’d learnt. Thankfully, the opposite is true: I’ve learnt a lot during my time here, and there has been a definite positive impact on the way I write code. The first thing I’ve really learnt is that test-driven development is, in general, a sensible way of working. Before coming, I didn’t really get it: how could you test something you hadn’t yet written? It didn’t make sense! My problem was seeing a test as having to test all the behaviour of a given function. Writing tests which test the bare minimum possible and building them up is a really good way of crystallising the direction the code needs to grow in, and ensures you never attempt to write too much code at time. One really good experience of this was early on in my internship when Mike and I were working on the query used to list active authors: I’d written something which I thought would do the trick, but by starting again using TDD we grew something which revealed that there were several subtle mistakes in the query I’d written. I’ve also been awakened to the value of pair programming. Whilst I could sort of see the point before coming, I also thought that it was impossible that two people would ever get more done at the same computer than if they were working separately. I still think that this is true for projects with pieces that developers can easily work on independently, and with developers who both know the codebase, but I’ve found that pair programming can be really good for learning a code base, and for building up small projects to the point where you can start working on separate components, as well as solving particularly difficult problems. Later on in my internship, for my down tools week project, I was working on adding Python support to Glimpse. Another intern and I we pair programmed the entire project, using ping pong pair programming as much as possible. One bonus that this brought which I wasn’t expecting was that I found myself less prone to distraction: with someone else peering over my shoulder, I didn’t have the ever-present temptation to open gmail, or facebook, or yammer, or twitter, or hacker news, or reddit, and so on, and so forth. I’m quite proud of this project: I think it’s some of the best code I’ve written. I’ve also been really won over to the value of descriptive variables names. In my pre-Red Gate life, as a lone-ranger style cowboy programmer, I’d developed a tendency towards laziness in variable names, sometimes abbreviating or, worse, using acronyms. I’ve swiftly realised that this is a bad idea when working with a team: saving a few key strokes is inevitably not worth it when it comes to reading code again in the future. Longer names also mean you can do away with a majority of comments. I appreciate that if you’ve come up with an O(n*log n) algorithm for something which seemed O(n^2), you probably want to explain how it works, but explaining what a variable name means is a big no no: it’s so very easy to change the behaviour of the code, whilst forgetting about the comments. Whilst at Red Gate, I took the opportunity to attend a code retreat, which really helped me to solidify all the things I’d learnt. To be completely free of any existing code base really lets you focus on best practises and think about how you write code. If you get a chance to go on a similar event, I’d highly recommend it! Cycling to Red Gate, I’ve also become much better at fitting inner tubes: if you’re struggling to get the tube out, or re-fit the tire, letting a bit of air out usually helps. I’ve also become quite a bit better at foosball and will miss having a foosball table! I’d like to finish off by saying thank you to everyone at Red Gate for having me. I’ve really enjoyed working with, and learning from, the team that brings you this web site. If you meet any of them, buy them a drink!

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• Benchmarking MySQL Replication with Multi-Threaded Slaves

  - by Mat Keep

  0 0 1 1145 6530 Homework 54 15 7660 14.0 Normal 0 false false false EN-US JA X-NONE /* 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-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:Cambria; mso-ascii-font-family:Cambria; mso-ascii-theme-font:minor-latin; mso-hansi-font-family:Cambria; mso-hansi-theme-font:minor-latin; mso-ansi-language:EN-US;} The objective of this benchmark is to measure the performance improvement achieved when enabling the Multi-Threaded Slave enhancement delivered as a part MySQL 5.6. As the results demonstrate, Multi-Threaded Slaves delivers 5x higher replication performance based on a configuration with 10 databases/schemas. For real-world deployments, higher replication performance directly translates to: · Improved consistency of reads from slaves (i.e. reduced risk of reading "stale" data) · Reduced risk of data loss should the master fail before replicating all events in its binary log (binlog) The multi-threaded slave splits processing between worker threads based on schema, allowing updates to be applied in parallel, rather than sequentially. This delivers benefits to those workloads that isolate application data using databases - e.g. multi-tenant systems deployed in cloud environments. Multi-Threaded Slaves are just one of many enhancements to replication previewed as part of the MySQL 5.6 Development Release, which include: · Global Transaction Identifiers coupled with MySQL utilities for automatic failover / switchover and slave promotion · Crash Safe Slaves and Binlog · Optimized Row Based Replication · Replication Event Checksums · Time Delayed Replication These and many more are discussed in the “MySQL 5.6 Replication: Enabling the Next Generation of Web & Cloud Services” Developer Zone article  Back to the benchmark - details are as follows. Environment The test environment consisted of two Linux servers: · one running the replication master · one running the replication slave. Only the slave was involved in the actual measurements, and was based on the following configuration: - Hardware: Oracle Sun Fire X4170 M2 Server - CPU: 2 sockets, 6 cores with hyper-threading, 2930 MHz. - OS: 64-bit Oracle Enterprise Linux 6.1 - Memory: 48 GB Test Procedure Initial Setup: Two MySQL servers were started on two different hosts, configured as replication master and slave. 10 sysbench schemas were created, each with a single table: CREATE TABLE `sbtest` (    `id` int(10) unsigned NOT NULL AUTO_INCREMENT,    `k` int(10) unsigned NOT NULL DEFAULT '0',    `c` char(120) NOT NULL DEFAULT '',    `pad` char(60) NOT NULL DEFAULT '',    PRIMARY KEY (`id`),    KEY `k` (`k`) ) ENGINE=InnoDB DEFAULT CHARSET=latin1 10,000 rows were inserted in each of the 10 tables, for a total of 100,000 rows. When the inserts had replicated to the slave, the slave threads were stopped. The slave data directory was copied to a backup location and the slave threads position in the master binlog noted. 10 sysbench clients, each configured with 10 threads, were spawned at the same time to generate a random schema load against each of the 10 schemas on the master. Each sysbench client executed 10,000 "update key" statements: UPDATE sbtest set k=k+1 WHERE id = <random row> In total, this generated 100,000 update statements to later replicate during the test itself. Test Methodology: The number of slave workers to test with was configured using: SET GLOBAL slave_parallel_workers=<workers> Then the slave IO thread was started and the test waited for all the update queries to be copied over to the relay log on the slave. The benchmark clock was started and then the slave SQL thread was started. The test waited for the slave SQL thread to finish executing the 100k update queries, doing "select master_pos_wait()". When master_pos_wait() returned, the benchmark clock was stopped and the duration calculated. The calculated duration from the benchmark clock should be close to the time it took for the SQL thread to execute the 100,000 update queries. The 100k queries divided by this duration gave the benchmark metric, reported as Queries Per Second (QPS). Test Reset: The test-reset cycle was implemented as follows: · the slave was stopped · the slave data directory replaced with the previous backup · the slave restarted with the slave threads replication pointer repositioned to the point before the update queries in the binlog. The test could then be repeated with identical set of queries but a different number of slave worker threads, enabling a fair comparison. The Test-Reset cycle was repeated 3 times for 0-24 number of workers and the QPS metric calculated and averaged for each worker count. MySQL Configuration The relevant configuration settings used for MySQL are as follows: binlog-format=STATEMENT relay-log-info-repository=TABLE master-info-repository=TABLE As described in the test procedure, the slave_parallel_workers setting was modified as part of the test logic. The consequence of changing this setting is: 0 worker threads:    - current (i.e. single threaded) sequential mode    - 1 x IO thread and 1 x SQL thread    - SQL thread both reads and executes the events 1 worker thread:    - sequential mode    - 1 x IO thread, 1 x Coordinator SQL thread and 1 x Worker thread    - coordinator reads the event and hands it to the worker who executes 2+ worker threads:    - parallel execution    - 1 x IO thread, 1 x Coordinator SQL thread and 2+ Worker threads    - coordinator reads events and hands them to the workers who execute them Results Figure 1 below shows that Multi-Threaded Slaves deliver ~5x higher replication performance when configured with 10 worker threads, with the load evenly distributed across our 10 x schemas. This result is compared to the current replication implementation which is based on a single SQL thread only (i.e. zero worker threads). Figure 1: 5x Higher Performance with Multi-Threaded Slaves The following figure shows more detailed results, with QPS sampled and reported as the worker threads are incremented. The raw numbers behind this graph are reported in the Appendix section of this post. Figure 2: Detailed Results As the results above show, the configuration does not scale noticably from 5 to 9 worker threads. When configured with 10 worker threads however, scalability increases significantly. The conclusion therefore is that it is desirable to configure the same number of worker threads as schemas. Other conclusions from the results: · Running with 1 worker compared to zero workers just introduces overhead without the benefit of parallel execution. · As expected, having more workers than schemas adds no visible benefit. Aside from what is shown in the results above, testing also demonstrated that the following settings had a very positive effect on slave performance: relay-log-info-repository=TABLE master-info-repository=TABLE For 5+ workers, it was up to 2.3 times as fast to run with TABLE compared to FILE. Conclusion As the results demonstrate, Multi-Threaded Slaves deliver significant performance increases to MySQL replication when handling multiple schemas. This, and the other replication enhancements introduced in MySQL 5.6 are fully available for you to download and evaluate now from the MySQL Developer site (select Development Release tab). You can learn more about MySQL 5.6 from the documentation  Please don’t hesitate to comment on this or other replication blogs with feedback and questions. Appendix – Detailed Results

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• CodePlex Daily Summary for Monday, July 15, 2013

  CodePlex Daily Summary for Monday, July 15, 2013Popular ReleasesMVC Forum: MVC Forum v1.0: Finally version 1.0 is here! We have been fixing a few bugs, and making sure the release is as stable as possible. We have also changed the way configuration of the application works, mostly how to add your own code or replace some of the standard code with your own. If you download and use our software, please give us some sort of feedback, good or bad!SharePoint 2013 TypeScript Definitions: Release 1.1: TypeScript 0.9 support SharePoint TypeScript Definitions are now compliant with the new version of TypeScript TypeScript generics are now used for defining collection classes (derivatives of SP.ClientCollection object) Improved coverage Added mQuery definitions (m$) Added SPClientAutoFill definitions SP.Utilities namespace is now fully covered SP.UI modal dialog definitions improved CSR definitions improved, added some missing methods and context properties, mostly related to list ...GoAgent GUI: GoAgent GUI ??? 1.0.0: ????GoAgent GUI????，???????????.Net Framework 4.0 ???????: Windows 8 x64 Windows 8 x86 Windows 7 x64 Windows 7 x86 ???????： Windows 8.1 Preview (x86/x64) ???????： Windows XP ????： ????????GoAgent????，????????，?????????????，???????????????????，??????????，????。PiGraph: PiGraph 2.0.8.13: C?p nh?t:Các l?i dã s?a: S?a l?i không nh?p du?c s? âm. L?i tabindex trong giao di?n Thêm hàm Các l?i chua kh?c ph?c: L?i ghi chú nh?p nháy màu. L?i khung ghi chú vu?t ra kh?i biên khi luu file. Luu ý:N?u không kh?i d?ng duoc chuong trình, b?n nên c?p nh?t driver card d? h?a phiên b?n m?i nh?t: AMD Graphics Drivers NVIDIA Driver Xem yêu c?u h? th?ngD3D9Client: D3D9Client R12 for Orbiter Beta: D3D9Client release for orbiter BetaVidCoder: 1.4.23: New in 1.4.23 Added French translation. Fixed non-x264 video encoders not sticking in video tab. New in 1.4 Updated HandBrake core to 0.9.9 Blu-ray subtitle (PGS) support Additional framerates: 30, 50, 59.94, 60 Additional sample rates: 8, 11.025, 12 and 16 kHz Additional higher bitrates for audio Same as Source Constant Framerate 24-bit FLAC encoding Added Windows Phone 8 and Apple TV 3 presets Introduced process isolation for encodes. Now if HandBrake crashes, VidCoder will ...Project Server 2013 Event Handler Admin Tool: PSI Event Admin Tool: Download & exract the File. Use LoggerAdmin to upload the event handlers in project server 2013. PSIEventLogger\LoggerAdmin\bin\DebugGherkin editor: Gherkin Editor Beta 2: Fix issue #7 and add some refactoring and code cleanupNew-NuGetPackage PowerShell Script: New-NuGetPackage.ps1 PowerShell Script v1.2: Show nuget gallery to push to when prompting user if they want to push their package.Site Templates By Steve: SharePoint 2010 CORE Site Theme By Steve WSP: Great Site Theme to start with from Steve. See project home page for install instructions. This is a nice centered, mega-menu, fixed width masterpage with styles. Remember to update the mega menu lists.SharePoint Solution Installer: SharePoint Solution Installer V1.2.8: setup2013.exe now supports CompatibilityLevel to target specific hive Use setup.exe for SP2007 & SP2010. Use setup2013.exe for SP2013.TBox - tool to make developer's life easier.: TBox 1.021: 1)Add console unit tests runner, to run unit tests in parallel from console. Also this new sub tool can save valid xml nunit report. It can help you in continuous integration. 2)Fix build scripts.LifeInSharepoint Modern UI Update: Version 2: Some minor improvements, including Audience Targeting support for quick launch links. Also removing all NextDocs references.Virtual Photonics: VTS MATLAB Package 1.0.13 Beta: This is the beta release of the MATLAB package with examples of using the VTS libraries within MATLAB. Changes for this release: Added two new examples to vts_solver_demo.m that: 1) generates and plots R(lambda) at a given rho, and chromophore concentrations assuming a power law for scattering, and 2) solves inverse problem for R(lambda) at given rho. This example solves for concentrations of HbO2, Hb and H20 given simulated measurements created using Nurbs scaled Monte Carlo and inverted u...Advanced Resource Tab for Blend: Advanced Resource Tab: This is the first alpha release of the advanced resource tab for Blend for Visual Studio 2012.Microsoft Ajax Minifier: Microsoft Ajax Minifier 4.96: Fix for issue #19957: EXE should output the name of the file(s) being minified. Discussion #449181: throw a Sev-2 warning when trailing commas are detected on an Array literal. Perfectly legal to do so, but the behavior ends up working differently on different browsers, so throw a cross-browser warning. Add a few more known global names for improved ES6 compatibility update Nuget package to version 2.5 and automatically add the AjaxMin.targets to your project when you update the package...Outlook 2013 Add-In: Categories and Colors: This new version has a major change in the drawing of the list items: - Using owner drawn code to format the appointments using GDI (some flickering may occur, but it looks a little bit better IMHO, with separate sections). - Added category color support (if more than one category, only one color will be shown). Here, the colors Outlook uses are slightly different than the ones available in System.Drawing, so I did a first approach matching. ;-) - Added appointment status support (to show fr...Columbus Remote Desktop: 2.0 Sapphire: Added configuration settings Added update notifications Added ability to disable GPU acceleration Fixed connection bugsLINQ to Twitter: LINQ to Twitter v2.1.07: Supports .NET 3.5, .NET 4.0, .NET 4.5, Silverlight 4.0, Windows Phone 7.1, Windows Phone 8, Client Profile, Windows 8, and Windows Azure. 100% Twitter API coverage. Also supports Twitter API v1.1! Also on NuGet.DotNetNuke® Community Edition CMS: 06.02.08: Major Highlights Fixed issue where the application throws an Unhandled Error and an HTTP Response Code of 200 when the connection to the database is lost. Security FixesNone Updated Modules/Providers ModulesNone ProvidersNoneNew Projects[.Net Intl] harroc_c;mallar_a;olouso_f: The goal of this project is to create a web crawler and a web front who allows you to search in your index. You will create a mini (or large!) search engine basButterfly Storage: Butterfly Storage is a data access technology based on object-oriented database model for Windows Store applications.KaveCompany: KaveCompleave that girl alone: a team project!MyClrProfiler: This project helps you learn about and develop your own CLR profiler.NETDeob: Deobfuscate obfuscated .NET files easilyProgram stomatologie: SummarySimple Graph Library: Simple portable class library for graphs data structures. .NET, Silverlight 4/5, Windows Phone, Windows RT, Xbox 360T6502 Emulator: T6502 is a 6502 emulator written in TypeScript using AngularJS. The goal is well-organized, readable code over performance.WP8 File Access Webserver: C# HTTP server and web application on Windows Phone 8. Implements file access, browsing and downloading.wpadk: wpadk????wp7?????? ?????????，?????、SDK、wpadk?????????????。??????????????????。??????????????????，????wpadk?????????????????????????????????????。xlmUnit: xlmUnit, Unit Testing

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• Physics System ignores collision in some rare cases

  - by Gajoo

  I've been developing a simple physics engine for my game. since the game physics is very simple I've decided to increase accuracy a little bit. Instead of formal integration methods like fourier or RK4, I'm directly computing the results after delta time "dt". based on the very first laws of physics : dx = 0.5 * a * dt^2 + v0 * dt dv = a * dt where a is acceleration and v0 is object's previous velocity. Also to handle collisions I've used a method which is somehow different from those I've seen so far. I'm detecting all the collision in the given time frame, stepping the world forward to the nearest collision, resolving it and again check for possible collisions. As I said the world consist of very simple objects, so I'm not loosing any performance due to multiple collision checking. First I'm checking if the ball collides with any walls around it (which is working perfectly) and then I'm checking if it collides with the edges of the walls (yellow points in the picture). the algorithm seems to work without any problem except some rare cases, in which the collision with points are ignored. I've tested everything and all the variables seem to be what they should but after leaving the system work for a minute or two the system the ball passes through one of those points. Here is collision portion of my code, hopefully one of you guys can give me a hint where to look for a potential bug! void PhysicalWorld::checkForPointCollision(Vec2 acceleration, PhysicsComponent& ball, Vec2& collisionNormal, float& collisionTime, Vec2 target) { // this function checks if there will be any collision between a circle and a point // ball contains informations about the circle (it's current velocity, position and radius) // collisionNormal is an output variable // collisionTime is also an output varialbe // target is the point I want to check for collisions Vec2 V = ball.mVelocity; Vec2 A = acceleration; Vec2 P = ball.mPosition - target; float wallWidth = mMap->getWallWidth() / (mMap->getWallWidth() + mMap->getHallWidth()) / 2; float r = ball.mRadius / (mMap->getWallWidth() + mMap->getHallWidth()); // r is ball radius scaled to match actual rendered object. if (A.any()) // todo : I need to first correctly solve the collisions in case there is no acceleration return; if (V.any()) // if object is not moving there will be no collisions! { float D = P.x * V.y - P.y * V.x; float Delta = r*r*V.length2() - D*D; if(Delta < eps) return; Delta = sqrt(Delta); float sgnvy = V.y > 0 ? 1: (V.y < 0?-1:0); Vec2 c1(( D*V.y+sgnvy*V.x*Delta) / V.length2(), (-D*V.x+fabs(V.y)*Delta) / V.length2()); Vec2 c2(( D*V.y-sgnvy*V.x*Delta) / V.length2(), (-D*V.x-fabs(V.y)*Delta) / V.length2()); float t1 = (c1.x - P.x) / V.x; float t2 = (c2.x - P.x) / V.x; if(t1 > eps && t1 <= collisionTime) { collisionTime = t1; collisionNormal = c1; } if(t2 > eps && t2 <= collisionTime) { collisionTime = t2; collisionNormal = c2; } } } // this function should step the world forward by dt. it doesn't check for collision of any two balls (components) // it just checks if there is a collision between the current component and 4 points forming a rectangle around it. void PhysicalWorld::step(float dt) { for (unsigned i=0;i<mObjects.size();i++) { PhysicsComponent &current = *mObjects[i]; Vec2 acceleration = current.mForces * current.mInvMass; float rt=dt; // stores how much more the world should advance while(rt > eps) { float collisionTime = rt; Vec2 collisionNormal = Vec2(0,0); float halfWallWidth = mMap->getWallWidth() / (mMap->getWallWidth() + mMap->getHallWidth()) / 2; // we check if there is any collision with any of those 4 points around the ball // if there is a collision both collisionNormal and collisionTime variables will change // after these functions collisionTime will be exactly the value of nearest collision (if any) // and if there was, collisionNormal will report in which direction the ball should return. checkForPointCollision(acceleration,current,collisionNormal,collisionTime,Vec2(floor(current.mPosition.x) + halfWallWidth,floor(current.mPosition.y) + halfWallWidth)); checkForPointCollision(acceleration,current,collisionNormal,collisionTime,Vec2(floor(current.mPosition.x) + halfWallWidth, ceil(current.mPosition.y) - halfWallWidth)); checkForPointCollision(acceleration,current,collisionNormal,collisionTime,Vec2( ceil(current.mPosition.x) - halfWallWidth,floor(current.mPosition.y) + halfWallWidth)); checkForPointCollision(acceleration,current,collisionNormal,collisionTime,Vec2( ceil(current.mPosition.x) - halfWallWidth, ceil(current.mPosition.y) - halfWallWidth)); // either if there is a collision or if there is not we step the forward since we are sure there will be no collision before collisionTime current.mPosition += collisionTime * (collisionTime * acceleration * 0.5 + current.mVelocity); current.mVelocity += collisionTime * acceleration; // if the ball collided with anything collisionNormal should be at least none zero in one of it's axis if (collisionNormal.any()) { collisionNormal *= Dot(collisionNormal, current.mVelocity) / collisionNormal.length2(); current.mVelocity -= 2 * collisionNormal; // simply reverse velocity along collision normal direction } rt -= collisionTime; } // reset all forces for current object so it'll be ready for later game event current.mForces.zero(); } }

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• Best way to store a large amount of game objects and update the ones onscreen

  - by user3002473

  Good afternoon guys! I'm a young beginner game developer working on my first large scale game project and I've run into a situation where I'm not quite sure what the best solution may be (if there is a lone solution). The question may be vague (if anyone can think of a better title after having read the question, please edit it) or broad but I'm not quite sure what to do and I thought it would help just to discuss the problem with people more educated in the field. Before we get started, here are some of the questions I've looked at for help in the past: Best way to keep track of game objects Elegant way to simulate large amounts of entities within a game world What is the most efficient container to store dynamic game objects in? I've also read articles about different data structures commonly used in games to store game objects such as this one about slot maps, but none of them are really what I'm looking for. Also, if it helps at all I'm using Python 3 to design the game. It has to be Python 3, if I could I would use C++ or Unityscript or something else, but I'm restricted to having to use Python 3. My game will be a form of side scroller shooter game. In said game the player will traverse large rooms with large amounts of enemies and other game objects to update (think some of the larger areas in Cave Story or Iji). The player obviously can't see the entire room all at once, so there is a viewport that follows the player around and renders only a selection of the room and the game objects that it contains. This is not a foreign concept. The part that's getting me confused has to do with how certain game objects are updated. Some of them are to be updated constantly, regardless of whether or not they can be seen. Other objects however are only to be updated when they are onscreen (for example, an enemy would only be updated to react to the player when it is onscreen or when it is in a certain range of the screen). Another problem is that game objects have to be easily referable by other game objects; something that happens in the player's update() method may affect another object in the world. Collision detection in games is always a serious problem. I need a way of containing the game objects such that it minimizes the number of cases when testing for collisions against one another. The final problem is that of creating and destroying game objects. I think this problem is pretty self explanatory. To store the game objects then I've considered a number of different methods. The original method I had was to simply store all the objects in a hash table by an id. This method was simple, and decently fast as it allows all the objects to be looked up in O(1) complexity, and also allows them to be deleted fairly easily. Hash collisions would not be a major problem; I wasn't originally planning on using computer generated ids to store the game objects I was going to rely on them all using ids given to them by the game designer (such names would be strings like 'Player' or 'EnemyWeapon4'), and even if I did use computer generated ids, if I used a decent hashing algorithm then the chances of collisions would be around 1 in 4 billion. The problem with using a hash table however is that it is inefficient in checking to see what objects are in range of the viewport. Considering the fact that certain game objects move (as well as the viewport itself), the only solution I could think of in order to only update objects that are in the viewport would be to iterate through every object in the hash table and check if it is in the viewport or not, updating only the ones that are in the valid area. This would be incredibly slow in scenarios where the amount of game objects exceeds 500, or even 200. The second solution was to store everything in a 2-d list. The world is partitioned up into cells (a tilemap essentially), where each cell or tile is the same size and is square. Each cell would contain a list of the game objects that are currently occupying it (each game object would be inserted into a cell depending on the center of the object's collision mask). A 2-d list would allow me to take the top-left and bottom-right corners of the viewport and easily grab a rectangular area of the grid containing only the cells containing entities that are in valid range to be updated. This method also solves the problem of collision detection; when I take an entity I can find the cell that it is currently in, then check only against entities in it's cell and the 8 cells around it. One problem with this system however is that it prohibits easy lookup of game objects. One solution I had would be to simultaneously keep a hash table that would contain all the positions of the objects in the 2-d list indexed by the id of said object. The major problem with a 2-d list is that it would need to be rebuilt every single game frame (along with the hash table of object positions), which may be a serious detriment to game speed. Both systems have ups and downs and seem to solve some of each other's problems, however using them both together doesn't seem like the best solution either. If anyone has any thoughts, ideas, suggestions, comments, opinions or solutions on new data structures or better implementations of the existing data structures I have in mind, please post, any and all criticism and help is welcome. Thanks in advance! EDIT: Please don't close the question because it has a bad title, I'm just bad with names!

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• Lenovo V570 CPU fan running constantly, CPU core 1 running over 90%!

  - by Rabbit2190

  I have seen that a lot of people are having this same issue. I am running a Lenovo V570 i5 4 core, 6 gigs of ram, and am running 11.10 Onieric Ocelot. On my system monitor graph it shows CPU at 20%, when I open the monitor it shows core #1 at around 90%, the other cores fluctuate at or below 5-12% if even. Now this seems like a really terrible balance of power between the cores, especially with so much stress on one core only, when these things are designed to work with 4 cores and not at such high temps. My current readings say 64 degrees Celsius, this does not seem normal for any cpu, and I am seriously considering, working on my windows7 partition until I see a real solution to this issue or upgrading to 12.04 right away when it comes out... I have seen countless things saying it has something to do with the Kernel, the kernel on mine is the same as when I upgraded, I really do not like messing with it, as when I had 11.04, I did tinker with it due to the freeze issues I was having, and that just made worse issues. I like this version 11.10 and would like to keep it for a while, but without the fear that my core is going to fry! So any help would be much appreciated! I did try changing a couple things in ACPI, and restarting this did not help, and here I am. I tried one thing prior to that that was listed under a different computer brand, but it would not do a make on the file. I really need help with this, I rely on this computer for a lot of things, and love this OS! Please help so I do not need to resort to my Microsoft partition! PLEASE! Here is the fwts cpufrequ- output: rabbit@rabbit-Lenovo-V570:~$ sudo fwts cpufreq - 00001 fwts Results generated by fwts: Version V0.23.25 (Thu Oct 6 15 00002 fwts :12:31 BST 2011). 00003 fwts 00004 fwts Some of this work - Copyright (c) 1999 - 2010, Intel Corp. 00005 fwts All rights reserved. 00006 fwts Some of this work - Copyright (c) 2010 - 2011, Canonical. 00007 fwts 00008 fwts This test run on 02/04/12 at 17:23:22 on host Linux 00009 fwts rabbit-Lenovo-V570 3.0.0-17-generic-pae #30-Ubuntu SMP Thu 00010 fwts Mar 8 17:53:35 UTC 2012 i686. 00011 fwts 00012 fwts Running tests: cpufreq. 00014 cpufreq CPU frequency scaling tests (takes ~1-2 mins). 00015 cpufreq --------------------------------------------------------- 00016 cpufreq Test 1 of 1: CPU P-State Checks. 00017 cpufreq For each processor in the system, this test steps through 00018 cpufreq the various frequency states (P-states) that the BIOS 00019 cpufreq advertises for the processor. For each processor/frequency 00020 cpufreq combination, a quick performance value is measured. The 00021 cpufreq test then validates that: 00022 cpufreq 1) Each processor has the same number of frequency states 00023 cpufreq 2) Higher advertised frequencies have a higher performance 00024 cpufreq 3) No duplicate frequency values are reported by the BIOS 00025 cpufreq 4) Is BIOS wrongly doing Sw_All P-state coordination across cores 00026 cpufreq 5) Is BIOS wrongly doing Sw_Any P-state coordination across cores 00027 cpufreq Frequency | Speed 00028 cpufreq -----------+--------- 00029 cpufreq 2.45 Ghz | 100.0 % 00030 cpufreq 2.45 Ghz | 83.7 % 00031 cpufreq 2.05 Ghz | 69.2 % 00032 cpufreq 1.85 Ghz | 62.5 % 00033 cpufreq 1.65 Ghz | 55.2 % 00034 cpufreq 1400 Mhz | 48.6 % 00035 cpufreq 1200 Mhz | 41.8 % 00036 cpufreq 1000 Mhz | 34.5 % 00037 cpufreq 800 Mhz | 27.6 % 00038 cpufreq 9 CPU frequency steps supported 00039 cpufreq Frequency | Speed 00040 cpufreq -----------+--------- 00041 cpufreq 2.45 Ghz | 97.7 % 00042 cpufreq 2.45 Ghz | 83.7 % 00043 cpufreq 2.05 Ghz | 69.6 % 00044 cpufreq 1.85 Ghz | 63.3 % 00045 cpufreq 1.65 Ghz | 55.7 % 00046 cpufreq 1400 Mhz | 48.7 % 00047 cpufreq 1200 Mhz | 41.7 % 00048 cpufreq 1000 Mhz | 34.5 % 00049 cpufreq 800 Mhz | 27.5 % 00050 cpufreq Frequency | Speed 00051 cpufreq -----------+--------- 00052 cpufreq 2.45 Ghz | 97.7 % 00053 cpufreq 2.45 Ghz | 84.4 % 00054 cpufreq 2.05 Ghz | 69.6 % 00055 cpufreq 1.85 Ghz | 62.6 % 00056 cpufreq 1.65 Ghz | 55.9 % 00057 cpufreq 1400 Mhz | 48.7 % 00058 cpufreq 1200 Mhz | 41.7 % 00059 cpufreq 1000 Mhz | 34.7 % 00060 cpufreq 800 Mhz | 27.8 % 00061 cpufreq Frequency | Speed 00062 cpufreq -----------+--------- 00063 cpufreq 2.45 Ghz | 100.0 % 00064 cpufreq 2.45 Ghz | 82.6 % 00065 cpufreq 2.05 Ghz | 67.8 % 00066 cpufreq 1.85 Ghz | 61.4 % 00067 cpufreq 1.65 Ghz | 54.9 % 00068 cpufreq 1400 Mhz | 48.3 % 00069 cpufreq 1200 Mhz | 41.1 % 00070 cpufreq 1000 Mhz | 34.3 % 00071 cpufreq 800 Mhz | 27.4 % 00072 cpufreq Frequency | Speed 00073 cpufreq -----------+--------- 00074 cpufreq 2.45 Ghz | 96.2 % 00075 cpufreq 2.45 Ghz | 82.5 % 00076 cpufreq 2.05 Ghz | 69.3 % 00077 cpufreq 1.85 Ghz | 62.7 % 00078 cpufreq 1.65 Ghz | 55.0 % 00079 cpufreq 1400 Mhz | 47.4 % 00080 cpufreq 1200 Mhz | 41.1 % 00081 cpufreq 1000 Mhz | 34.0 % 00082 cpufreq 800 Mhz | 27.2 % 00083 cpufreq Frequency | Speed 00084 cpufreq -----------+--------- 00085 cpufreq 2.45 Ghz | 96.5 % 00086 cpufreq 2.45 Ghz | 83.6 % 00087 cpufreq 2.05 Ghz | 68.1 % 00088 cpufreq 1.85 Ghz | 61.7 % 00089 cpufreq 1.65 Ghz | 54.9 % 00090 cpufreq 1400 Mhz | 48.0 % 00091 cpufreq 1200 Mhz | 41.1 % 00092 cpufreq 1000 Mhz | 34.2 % 00093 cpufreq 800 Mhz | 27.8 % 00094 cpufreq Frequency | Speed 00095 cpufreq -----------+--------- 00096 cpufreq 2.45 Ghz | 96.4 % 00097 cpufreq 2.45 Ghz | 82.6 % 00098 cpufreq 2.05 Ghz | 68.8 % 00099 cpufreq 1.85 Ghz | 60.5 % 00100 cpufreq 1.65 Ghz | 52.4 % 00101 cpufreq 1400 Mhz | 48.8 % 00102 cpufreq 1200 Mhz | 41.1 % 00103 cpufreq 1000 Mhz | 34.2 % 00104 cpufreq 800 Mhz | 26.4 % 00105 cpufreq Frequency | Speed 00106 cpufreq -----------+--------- 00107 cpufreq 2.45 Ghz | 95.3 % 00108 cpufreq 2.45 Ghz | 82.5 % 00109 cpufreq 2.05 Ghz | 65.5 % 00110 cpufreq 1.85 Ghz | 62.8 % 00111 cpufreq 1.65 Ghz | 54.8 % 00112 cpufreq 1400 Mhz | 48.0 % 00113 cpufreq 1200 Mhz | 41.2 % 00114 cpufreq 1000 Mhz | 34.2 % 00115 cpufreq 800 Mhz | 27.3 % 00116 cpufreq Frequency | Speed 00117 cpufreq -----------+--------- 00118 cpufreq 2.45 Ghz | 96.3 % 00119 cpufreq 2.45 Ghz | 83.4 % 00120 cpufreq 2.05 Ghz | 68.3 % 00121 cpufreq 1.85 Ghz | 61.9 % 00122 cpufreq 1.65 Ghz | 54.9 % 00123 cpufreq 1400 Mhz | 48.0 % 00124 cpufreq 1200 Mhz | 41.1 % 00125 cpufreq 1000 Mhz | 34.2 % 00126 cpufreq 800 Mhz | 27.3 % 00127 cpufreq Frequency | Speed 00128 cpufreq -----------+--------- 00129 cpufreq 2.45 Ghz | 100.0 % 00130 cpufreq 2.45 Ghz | 77.9 % 00131 cpufreq 2.05 Ghz | 64.6 % 00132 cpufreq 1.85 Ghz | 54.0 % 00133 cpufreq 1.65 Ghz | 51.7 % 00134 cpufreq 1400 Mhz | 45.2 % 00135 cpufreq 1200 Mhz | 39.0 % 00136 cpufreq 1000 Mhz | 33.1 % 00137 cpufreq 800 Mhz | 25.5 % 00138 cpufreq Frequency | Speed 00139 cpufreq -----------+--------- 00140 cpufreq 2.45 Ghz | 93.4 % 00141 cpufreq 2.45 Ghz | 75.7 % 00142 cpufreq 2.05 Ghz | 64.5 % 00143 cpufreq 1.85 Ghz | 59.1 % 00144 cpufreq 1.65 Ghz | 51.4 % 00145 cpufreq 1400 Mhz | 45.9 % 00146 cpufreq 1200 Mhz | 39.3 % 00147 cpufreq 1000 Mhz | 32.7 % 00148 cpufreq 800 Mhz | 25.8 % 00149 cpufreq Frequency | Speed 00150 cpufreq -----------+--------- 00151 cpufreq 2.45 Ghz | 92.1 % 00152 cpufreq 2.45 Ghz | 78.1 % 00153 cpufreq 2.05 Ghz | 65.7 % 00154 cpufreq 1.85 Ghz | 58.6 % 00155 cpufreq 1.65 Ghz | 52.5 % 00156 cpufreq 1400 Mhz | 45.7 % 00157 cpufreq 1200 Mhz | 39.3 % 00158 cpufreq 1000 Mhz | 32.7 % 00159 cpufreq 800 Mhz | 24.3 % 00160 cpufreq Frequency | Speed 00161 cpufreq -----------+--------- 00162 cpufreq 2.45 Ghz | 88.9 % 00163 cpufreq 2.45 Ghz | 79.8 % 00164 cpufreq 2.05 Ghz | 58.4 % 00165 cpufreq 1.85 Ghz | 52.6 % 00166 cpufreq 1.65 Ghz | 46.9 % 00167 cpufreq 1400 Mhz | 41.0 % 00168 cpufreq 1200 Mhz | 35.1 % 00169 cpufreq 1000 Mhz | 29.1 % 00170 cpufreq 800 Mhz | 22.9 % 00171 cpufreq Frequency | Speed 00172 cpufreq -----------+--------- 00173 cpufreq 2.45 Ghz | 92.8 % 00174 cpufreq 2.45 Ghz | 80.1 % 00175 cpufreq 2.05 Ghz | 66.2 % 00176 cpufreq 1.85 Ghz | 59.5 % 00177 cpufreq 1.65 Ghz | 52.9 % 00178 cpufreq 1400 Mhz | 46.2 % 00179 cpufreq 1200 Mhz | 39.5 % 00180 cpufreq 1000 Mhz | 32.9 % 00181 cpufreq 800 Mhz | 26.3 % 00182 cpufreq Frequency | Speed 00183 cpufreq -----------+--------- 00184 cpufreq 2.45 Ghz | 92.9 % 00185 cpufreq 2.45 Ghz | 79.5 % 00186 cpufreq 2.05 Ghz | 66.2 % 00187 cpufreq 1.85 Ghz | 59.6 % 00188 cpufreq 1.65 Ghz | 52.9 % 00189 cpufreq 1400 Mhz | 46.7 % 00190 cpufreq 1200 Mhz | 39.6 % 00191 cpufreq 1000 Mhz | 32.9 % 00192 cpufreq 800 Mhz | 26.3 % 00193 cpufreq FAILED [MEDIUM] CPUFreqCPUsSetToSW_ANY: Test 1, Processors 00194 cpufreq are set to SW_ANY. 00195 cpufreq FAILED [MEDIUM] CPUFreqSW_ANY: Test 1, Firmware not 00196 cpufreq implementing hardware coordination cleanly. Firmware using 00197 cpufreq SW_ANY instead?. 00198 cpufreq 00199 cpufreq ========================================================= 00200 cpufreq 0 passed, 2 failed, 0 warnings, 0 aborted, 0 skipped, 0 00201 cpufreq info only. 00202 cpufreq ========================================================= 00204 summary 00205 summary 0 passed, 2 failed, 0 warnings, 0 aborted, 0 skipped, 0 00206 summary info only. 00207 summary 00208 summary Test Failure Summary 00209 summary ==================== 00210 summary 00211 summary Critical failures: NONE 00212 summary 00213 summary High failures: NONE 00214 summary 00215 summary Medium failures: 2 00216 summary cpufreq test, at 1 log line: 193 00217 summary "Processors are set to SW_ANY." 00218 summary cpufreq test, at 1 log line: 195 00219 summary "Firmware not implementing hardware coordination cleanly. Firmware using SW_ANY instead?." 00220 summary 00221 summary Low failures: NONE 00222 summary 00223 summary Other failures: NONE 00224 summary 00225 summary Test |Pass |Fail |Abort|Warn |Skip |Info | 00226 summary ---------------+-----+-----+-----+-----+-----+-----+ 00227 summary cpufreq | | 2| | | | | 00228 summary ---------------+-----+-----+-----+-----+-----+-----+ 00229 summary Total: | 0| 2| 0| 0| 0| 0| 00230 summary ---------------+-----+-----+-----+-----+-----+-----+ rabbit@rabbit-Lenovo-V570:~$

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• Repeated disconnects on WPA PEAP network

  - by exasperated

  My school has a WPA PEAP network with GTC inner authentication. I am able to connect to the network, but once I load a website or two, the network become unresponsive (i.e. in Chromium, it gets stuck at "Sending request"), and I'm eventually disconnected. Any help will be greatly appreciated. Here's some log output. I can provide more if needed: Ubuntu 13.04 3.8.0-32-generic x86_64 lsusb: 03:00.0 Network controller: Intel Corporation Centrino Advanced-N 6235 (rev 24) lsmod: iwldvm                241872  0  mac80211              606457  1 iwldvm iwlwifi               173516  1 iwldvm cfg80211              511019  3 iwlwifi,mac80211,iwldvm dmesg: [    3.501227] iwlwifi 0000:03:00.0: irq 46 for MSI/MSI-X [    3.503541] iwlwifi 0000:03:00.0: loaded firmware version 18.168.6.1 [    3.527153] iwlwifi 0000:03:00.0: CONFIG_IWLWIFI_DEBUG disabled [    3.527162] iwlwifi 0000:03:00.0: CONFIG_IWLWIFI_DEBUGFS enabled [    3.527170] iwlwifi 0000:03:00.0: CONFIG_IWLWIFI_DEVICE_TRACING enabled [    3.527178] iwlwifi 0000:03:00.0: CONFIG_IWLWIFI_DEVICE_TESTMODE enabled [    3.527186] iwlwifi 0000:03:00.0: CONFIG_IWLWIFI_P2P disabled [    3.527192] iwlwifi 0000:03:00.0: Detected Intel(R) Centrino(R) Advanced-N 6235 AGN, REV=0xB0 [    3.527240] iwlwifi 0000:03:00.0: L1 Disabled; Enabling L0S [    3.551049] ieee80211 phy0: Selected rate control algorithm 'iwl-agn-rs' [  375.153065] iwlwifi 0000:03:00.0: L1 Disabled; Enabling L0S [  375.159727] iwlwifi 0000:03:00.0: Radio type=0x2-0x1-0x0 [  375.553201] iwlwifi 0000:03:00.0: L1 Disabled; Enabling L0S [  375.559871] iwlwifi 0000:03:00.0: Radio type=0x2-0x1-0x0 [ 1892.110738] iwlwifi 0000:03:00.0: L1 Disabled; Enabling L0S [ 1892.117357] iwlwifi 0000:03:00.0: Radio type=0x2-0x1-0x0 [ 5227.235372] iwlwifi 0000:03:00.0: L1 Disabled; Enabling L0S [ 5227.242122] iwlwifi 0000:03:00.0: Radio type=0x2-0x1-0x0 [ 5817.817954] iwlwifi 0000:03:00.0: L1 Disabled; Enabling L0S [ 5817.824560] iwlwifi 0000:03:00.0: Radio type=0x2-0x1-0x0 [ 5824.571917] iwlwifi 0000:03:00.0 wlan0: disabling HT/VHT due to WEP/TKIP use [ 5824.571929] iwlwifi 0000:03:00.0 wlan0: disabling HT as WMM/QoS is not supported by the AP [ 5824.571935] iwlwifi 0000:03:00.0 wlan0: disabling VHT as WMM/QoS is not supported by the AP [ 6956.290061] iwlwifi 0000:03:00.0: L1 Disabled; Enabling L0S [ 6956.296671] iwlwifi 0000:03:00.0: Radio type=0x2-0x1-0x0 [ 6963.080560] iwlwifi 0000:03:00.0 wlan0: disabling HT/VHT due to WEP/TKIP use [ 6963.080566] iwlwifi 0000:03:00.0 wlan0: disabling HT as WMM/QoS is not supported by the AP [ 6963.080570] iwlwifi 0000:03:00.0 wlan0: disabling VHT as WMM/QoS is not supported by the AP [ 7613.469241] iwlwifi 0000:03:00.0: L1 Disabled; Enabling L0S [ 7613.475870] iwlwifi 0000:03:00.0: Radio type=0x2-0x1-0x0 [ 7620.201265] iwlwifi 0000:03:00.0 wlan0: disabling HT/VHT due to WEP/TKIP use [ 7620.201278] iwlwifi 0000:03:00.0 wlan0: disabling HT as WMM/QoS is not supported by the AP [ 7620.201285] iwlwifi 0000:03:00.0 wlan0: disabling VHT as WMM/QoS is not supported by the AP [ 8232.762453] iwlwifi 0000:03:00.0: L1 Disabled; Enabling L0S [ 8232.769065] iwlwifi 0000:03:00.0: Radio type=0x2-0x1-0x0 [ 8239.581772] iwlwifi 0000:03:00.0 wlan0: disabling HT/VHT due to WEP/TKIP use [ 8239.581784] iwlwifi 0000:03:00.0 wlan0: disabling HT as WMM/QoS is not supported by the AP [ 8239.581792] iwlwifi 0000:03:00.0 wlan0: disabling VHT as WMM/QoS is not supported by the AP [13763.634808] iwlwifi 0000:03:00.0: L1 Disabled; Enabling L0S [13763.641427] iwlwifi 0000:03:00.0: Radio type=0x2-0x1-0x0 [16955.598953] iwlwifi 0000:03:00.0: L1 Disabled; Enabling L0S [16955.605574] iwlwifi 0000:03:00.0: Radio type=0x2-0x1-0x0 lshw:    *-network        description: Wireless interface        product: Centrino Advanced-N 6235        vendor: Intel Corporation        physical id: 0        bus info: pci@0000:03:00.0        logical name: wlan0        version: 24        serial: b4:b6:76:a0:4b:3c        width: 64 bits        clock: 33MHz        capabilities: pm msi pciexpress bus_master cap_list ethernet physical wireless        configuration: broadcast=yes driver=iwlwifi driverversion=3.8.0-32-generic firmware=18.168.6.1 ip=10.250.169.96 latency=0 link=yes multicast=yes wireless=IEEE 802.11abgn        resources: irq:46 memory:f7c00000-f7c01fff iwlist scan: Cell 02 - Address: 24:DE:C6:B0:C7:D9                     Channel:36                     Frequency:5.18 GHz (Channel 36)                     Quality=29/70  Signal level=-81 dBm                       Encryption key:on                     ESSID:"CatChat2x"                     Bit Rates:6 Mb/s; 9 Mb/s; 12 Mb/s; 18 Mb/s; 24 Mb/s                               36 Mb/s; 48 Mb/s; 54 Mb/s                     Mode:Master                     Extra:tsf=0000004ff3fe419b                     Extra: Last beacon: 27820ms ago                     IE: Unknown: 0009436174436861743278                     IE: Unknown: 01088C129824B048606C                     IE: Unknown: 030124                     IE: IEEE 802.11i/WPA2 Version 1                         Group Cipher : CCMP                         Pairwise Ciphers (1) : CCMP                         Authentication Suites (1) : 802.1x                     IE: Unknown: 2D1ACC011BFFFF000000000000000000000000000000000000000000                     IE: Unknown: 3D1624001B000000FF000000000000000000000000000000                     IE: Unknown: DD180050F2020101800003A4000027A4000042435E0062322F00                     IE: Unknown: DD1E00904C33CC011BFFFF000000000000000000000000000000000000000000                     IE: Unknown: DD1A00904C3424001B000000FF000000000000000000000000000000           Cell 04 - Address: 24:DE:C6:B0:C3:E9                     Channel:149                     Frequency:5.745 GHz                     Quality=28/70  Signal level=-82 dBm                       Encryption key:on                     ESSID:"CatChat2x"                     Bit Rates:6 Mb/s; 9 Mb/s; 12 Mb/s; 18 Mb/s; 24 Mb/s                               36 Mb/s; 48 Mb/s; 54 Mb/s                     Mode:Master                     Extra:tsf=000000181f60e19c                     Extra: Last beacon: 28680ms ago                     IE: Unknown: 0009436174436861743278                     IE: Unknown: 01088C129824B048606C                     IE: Unknown: 030195                     IE: Unknown: 050400010000                     IE: IEEE 802.11i/WPA2 Version 1                         Group Cipher : CCMP                         Pairwise Ciphers (1) : CCMP                         Authentication Suites (1) : 802.1x                     IE: Unknown: 2D1ACC011BFFFF000000000000000000000000000000000000000000                     IE: Unknown: 3D1695001B000000FF000000000000000000000000000000                     IE: Unknown: DD180050F2020101800003A4000027A4000042435E0062322F00                     IE: Unknown: DD1E00904C33CC011BFFFF000000000000000000000000000000000000000000                     IE: Unknown: DD1A00904C3495001B000000FF000000000000000000000000000000                     IE: Unknown: DD07000B8601040817                     IE: Unknown: DD0E000B860103006170313930333032           Cell 09 - Address: 24:DE:C6:B0:C0:29                     Channel:149                     Frequency:5.745 GHz                     Quality=39/70  Signal level=-71 dBm                       Encryption key:on                     ESSID:"CatChat2x"                     Bit Rates:6 Mb/s; 9 Mb/s; 12 Mb/s; 18 Mb/s; 24 Mb/s                               36 Mb/s; 48 Mb/s; 54 Mb/s                     Mode:Master                     Extra:tsf=00000112fb688ede                     Extra: Last beacon: 27716ms ago ifconfig (while connected): wlan0     Link encap:Ethernet  HWaddr b4:b6:76:a0:4b:3c             inet addr:10.250.16.220  Bcast:10.250.31.255  Mask:255.255.240.0           inet6 addr: fe80::b6b6:76ff:fea0:4b3c/64 Scope:Link           UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1           RX packets:230023 errors:0 dropped:0 overruns:0 frame:0           TX packets:130970 errors:0 dropped:0 overruns:0 carrier:0           collisions:0 txqueuelen:1000            RX bytes:255999759 (255.9 MB)  TX bytes:16652605 (16.6 MB) iwconfig (while connected): wlan0     IEEE 802.11abgn  ESSID:"CatChat2x"             Mode:Managed  Frequency:5.745 GHz  Access Point: 24:DE:C6:B0:C0:29              Bit Rate=6 Mb/s   Tx-Power=15 dBm              Retry  long limit:7   RTS thr:off   Fragment thr:off           Power Management:off           Link Quality=36/70  Signal level=-74 dBm             Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0           Tx excessive retries:0  Invalid misc:3   Missed beacon:0

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• Augmenting your Social Efforts via Data as a Service (DaaS)

  - by Mike Stiles

  The following is the 3rd in a series of posts on the value of leveraging social data across your enterprise by Oracle VP Product Development Don Springer and Oracle Cloud Data and Insight Service Sr. Director Product Management Niraj Deo. In this post, we will discuss the approach and value of integrating additional “public” data via a cloud-based Data-as-as-Service platform (or DaaS) to augment your Socially Enabled Big Data Analytics and CX Management. Let’s assume you have a functional Social-CRM platform in place. You are now successfully and continuously listening and learning from your customers and key constituents in Social Media, you are identifying relevant posts and following up with direct engagement where warranted (both 1:1, 1:community, 1:all), and you are starting to integrate signals for communication into your appropriate Customer Experience (CX) Management systems as well as insights for analysis in your business intelligence application. What is the next step? Augmenting Social Data with other Public Data for More Advanced Analytics When we say advanced analytics, we are talking about understanding causality and correlation from a wide variety, volume and velocity of data to Key Performance Indicators (KPI) to achieve and optimize business value. And in some cases, to predict future performance to make appropriate course corrections and change the outcome to your advantage while you can. The data to acquire, process and analyze this is very nuanced: It can vary across structured, semi-structured, and unstructured data It can span across content, profile, and communities of profiles data It is increasingly public, curated and user generated The key is not just getting the data, but making it value-added data and using it to help discover the insights to connect to and improve your KPIs. As we spend time working with our larger customers on advanced analytics, we have seen a need arise for more business applications to have the ability to ingest and use “quality” curated, social, transactional reference data and corresponding insights. The challenge for the enterprise has been getting this data inline into an easily accessible system and providing the contextual integration of the underlying data enriched with insights to be exported into the enterprise’s business applications. The following diagram shows the requirements for this next generation data and insights service or (DaaS): Some quick points on these requirements: Public Data, which in this context is about Common Business Entities, such as - Customers, Suppliers, Partners, Competitors (all are organizations) Contacts, Consumers, Employees (all are people) Products, Brands This data can be broadly categorized incrementally as - Base Utility data (address, industry classification) Public Master Reference data (trade style, hierarchy) Social/Web data (News, Feeds, Graph) Transactional Data generated by enterprise process, workflows etc. This Data has traits of high-volume, variety, velocity etc., and the technology needed to efficiently integrate this data for your needs includes - Change management of Public Reference Data across all categories Applied Big Data to extract statics as well as real-time insights Knowledge Diagnostics and Data Mining As you consider how to deploy this solution, many of our customers will be using an online “cloud” service that provides quality data and insights uniformly to all their necessary applications. In addition, they are requesting a service that is: Agile and Easy to Use: Applications integrated with the service can obtain data on-demand, quickly and simply Cost-effective: Pre-integrated into applications so customers don’t have to Has High Data Quality: Single point access to reference data for data quality and linkages to transactional, curated and social data Supports Data Governance: Becomes more manageable and cost-effective since control of data privacy and compliance can be enforced in a centralized place Data-as-a-Service (DaaS) Just as the cloud has transformed and now offers a better path for how an enterprise manages its IT from their infrastructure, platform, and software (IaaS, PaaS, and SaaS), the next step is data (DaaS). Over the last 3 years, we have seen the market begin to offer a cloud-based data service and gain initial traction. On one side of the DaaS continuum, we see an “appliance” type of service that provides a single, reliable source of accurate business data plus social information about accounts, leads, contacts, etc. On the other side of the continuum we see more of an online market “exchange” approach where ISVs and Data Publishers can publish and sell premium datasets within the exchange, with the exchange providing a rich set of web interfaces to improve the ease of data integration. Why the difference? It depends on the provider’s philosophy on how fast the rate of commoditization of certain data types will occur. How do you decide the best approach? Our perspective, as shown in the diagram below, is that the enterprise should develop an elastic schema to support multi-domain applicability. This allows the enterprise to take the most flexible approach to harness the speed and breadth of public data to achieve value. The key tenet of the proposed approach is that an enterprise carefully federates common utility, master reference data end points, mobility considerations and content processing, so that they are pervasively available. One way you may already be familiar with this approach is in how you do Address Verification treatments for accounts, contacts etc. If you design and revise this service in such a way that it is also easily available to social analytic needs, you could extend this to launch geo-location based social use cases (marketing, sales etc.). Our fundamental belief is that value-added data achieved through enrichment with specialized algorithms, as well as applying business “know-how” to weight-factor KPIs based on innovative combinations across an ever-increasing variety, volume and velocity of data, will be where real value is achieved. Essentially, Data-as-a-Service becomes a single entry point for the ever-increasing richness and volume of public data, with enrichment and combined capabilities to extract and integrate the right data from the right sources with the right factoring at the right time for faster decision-making and action within your core business applications. As more data becomes available (and in many cases commoditized), this value-added data processing approach will provide you with ongoing competitive advantage. Let’s look at a quick example of creating a master reference relationship that could be used as an input for a variety of your already existing business applications. In phase 1, a simple master relationship is achieved between a company (e.g. General Motors) and a variety of car brands’ social insights. The reference data allows for easy sort, export and integration into a set of CRM use cases for analytics, sales and marketing CRM. In phase 2, as you create more data relationships (e.g. competitors, contacts, other brands) to have broader and deeper references (social profiles, social meta-data) for more use cases across CRM, HCM, SRM, etc. This is just the tip of the iceberg, as the amount of master reference relationships is constrained only by your imagination and the availability of quality curated data you have to work with. DaaS is just now emerging onto the marketplace as the next step in cloud transformation. For some of you, this may be the first you have heard about it. Let us know if you have questions, or perspectives. In the meantime, we will continue to share insights as we can.Photo: Erik Araujo, stock.xchng

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• Atheros 922 PCI WIFI is disabled in Unity but enabled in terminal - How to get it to work?

  - by zewone

  I am trying to get my PCI Wireless Atheros 922 card to work. It is disabled in Unity: both the network utility and the desktop (see screenshot http://www.amisdurailhalanzy.be/Screenshot%20from%202012-10-25%2013:19:54.png) I tried many different advises on many different forums. Installed 12.10 instead of 12.04, enabled all interfaces... etc. I have read about the aht9 driver... The terminal shows no hw or sw lock for the Atheros card, nevertheless, it is still disabled. Nothing worked so far, the card is still disabled. Any help is much appreciated. Here are more tech details: myuser@adri1:~$ sudo lshw -C network *-network:0 DISABLED description: Wireless interface product: AR922X Wireless Network Adapter vendor: Atheros Communications Inc. physical id: 2 bus info: pci@0000:03:02.0 logical name: wlan1 version: 01 serial: 00:18:e7:cd:68:b1 width: 32 bits clock: 66MHz capabilities: pm bus_master cap_list ethernet physical wireless configuration: broadcast=yes driver=ath9k driverversion=3.5.0-17-generic firmware=N/A latency=168 link=no multicast=yes wireless=IEEE 802.11bgn resources: irq:18 memory:d8000000-d800ffff *-network:1 description: Ethernet interface product: VT6105/VT6106S [Rhine-III] vendor: VIA Technologies, Inc. physical id: 6 bus info: pci@0000:03:06.0 logical name: eth0 version: 8b serial: 00:11:09:a3:76:4a size: 10Mbit/s capacity: 100Mbit/s width: 32 bits clock: 33MHz capabilities: pm bus_master cap_list ethernet physical tp mii 10bt 10bt-fd 100bt 100bt-fd autonegotiation configuration: autonegotiation=on broadcast=yes driver=via-rhine driverversion=1.5.0 duplex=half latency=32 link=no maxlatency=8 mingnt=3 multicast=yes port=MII speed=10Mbit/s resources: irq:18 ioport:d300(size=256) memory:d8013000-d80130ff *-network DISABLED description: Wireless interface physical id: 1 bus info: usb@1:8.1 logical name: wlan0 serial: 00:11:09:51:75:36 capabilities: ethernet physical wireless configuration: broadcast=yes driver=rt2500usb driverversion=3.5.0-17-generic firmware=N/A link=no multicast=yes wireless=IEEE 802.11bg myuser@adri1:~$ sudo rfkill list all 0: hci0: Bluetooth Soft blocked: no Hard blocked: no 1: phy1: Wireless LAN Soft blocked: no Hard blocked: yes 2: phy0: Wireless LAN Soft blocked: no Hard blocked: no myuser@adri1:~$ dmesg | grep wlan0 [ 15.114235] IPv6: ADDRCONF(NETDEV_UP): wlan0: link is not ready myuser@adri1:~$ dmesg | egrep 'ath|firm' [ 14.617562] ath: EEPROM regdomain: 0x30 [ 14.617568] ath: EEPROM indicates we should expect a direct regpair map [ 14.617572] ath: Country alpha2 being used: AM [ 14.617575] ath: Regpair used: 0x30 [ 14.637778] ieee80211 phy0: >Selected rate control algorithm 'ath9k_rate_control' [ 14.639410] Registered led device: ath9k-phy0 myuser@adri1:~$ dmesg | grep wlan1 [ 15.119922] IPv6: ADDRCONF(NETDEV_UP): wlan1: link is not ready myuser@adri1:~$ lspci -nn | grep 'Atheros' 03:02.0 Network controller [0280]: Atheros Communications Inc. AR922X Wireless Network Adapter [168c:0029] (rev 01) myuser@adri1:~$ sudo ifconfig eth0 Link encap:Ethernet HWaddr 00:11:09:a3:76:4a inet addr:192.168.2.2 Bcast:192.168.2.255 Mask:255.255.255.0 inet6 addr: fe80::211:9ff:fea3:764a/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:5457 errors:0 dropped:0 overruns:0 frame:0 TX packets:2548 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:3425684 (3.4 MB) TX bytes:282192 (282.1 KB) lo Link encap:Local Loopback inet addr:127.0.0.1 Mask:255.0.0.0 inet6 addr: ::1/128 Scope:Host UP LOOPBACK RUNNING MTU:16436 Metric:1 RX packets:590 errors:0 dropped:0 overruns:0 frame:0 TX packets:590 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:53729 (53.7 KB) TX bytes:53729 (53.7 KB) myuser@adri1:~$ sudo iwconfig wlan0 IEEE 802.11bg ESSID:off/any Mode:Managed Access Point: Not-Associated Tx-Power=off Retry long limit:7 RTS thr:off Fragment thr:off Encryption key:off Power Management:on lo no wireless extensions. eth0 no wireless extensions. wlan1 IEEE 802.11bgn ESSID:off/any Mode:Managed Access Point: Not-Associated Tx-Power=0 dBm Retry long limit:7 RTS thr:off Fragment thr:off Encryption key:off Power Management:off myuser@adri1:~$ lsmod | grep "ath9k" ath9k 116549 0 mac80211 461161 3 rt2x00usb,rt2x00lib,ath9k ath9k_common 13783 1 ath9k ath9k_hw 376155 2 ath9k,ath9k_common ath 19187 3 ath9k,ath9k_common,ath9k_hw cfg80211 175375 4 rt2x00lib,ath9k,mac80211,ath myuser@adri1:~$ iwlist scan wlan0 Failed to read scan data : Network is down lo Interface doesn't support scanning. eth0 Interface doesn't support scanning. wlan1 Failed to read scan data : Network is down myuser@adri1:~$ lsb_release -d Description: Ubuntu 12.10 myuser@adri1:~$ uname -mr 3.5.0-17-generic i686  Any help much appreciated... Thanks, Philippe 31-10-2012 ... I have some more updates. When I do the following command it does see my Wifi router... So even if it is still disabled... the card seems to work and see the router (ESSID:"5791BC26-CE9C-11D1-97BF-0000F81E") See below: sudo iwlist wlan1 scanning wlan1 Scan completed : Cell 01 - Address: 00:19:70:8F:B0:EA Channel:10 Frequency:2.457 GHz (Channel 10) Quality=51/70 Signal level=-59 dBm Encryption key:on ESSID:"5791BC26-CE9C-11D1-97BF-0000F81E" Bit Rates:1 Mb/s; 2 Mb/s; 5.5 Mb/s; 11 Mb/s; 6 Mb/s 9 Mb/s; 12 Mb/s; 18 Mb/s Bit Rates:24 Mb/s; 36 Mb/s; 48 Mb/s; 54 Mb/s Mode:Master Extra:tsf=000000025dbf2188 Extra: Last beacon: 108ms ago IE: Unknown: 002035373931424332362D434539432D313144312D393742462D3030303046383145 IE: Unknown: 010882848B960C121824 IE: Unknown: 03010A IE: Unknown: 0706424520010D14 IE: IEEE 802.11i/WPA2 Version 1 Group Cipher : TKIP Pairwise Ciphers (2) : CCMP TKIP Authentication Suites (1) : PSK IE: Unknown: 2A0100 IE: Unknown: 32043048606C IE: Unknown: DD180050F2020101030003A4000027A4000042435E0062322F00 IE: Unknown: DD0900037F01010000FF7F IE: Unknown: DD0A00037F04010000000000

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• CodePlex Daily Summary for Monday, August 18, 2014

  CodePlex Daily Summary for Monday, August 18, 2014Popular ReleasesMagick.NET: Magick.NET 7.0.0.0001: Magick.NET linked with ImageMagick 7-Beta.CMake Tools for Visual Studio: CMake Tools for Visual Studio 1.2: This release adds the following new features and bug fixes from CMake Tools for Visual Studio 1.1: Added support for CMake 3.0. Added support for word completion. Added IntelliSense support for the CMAKEHOSTSYSTEM_INFORMATION command. Fixed syntax highlighting for tokens beginning with escape sequences. Fixed issue uninstalling CMake Tools for Visual Studio after Visual Studio has been uninstalled.GW2 Personal Assistant Overlay: GW2 Personal Assistant Overlay 1.1: Overview1.1 is the second 'stable' release of the GW2 Personal Assistant Overlay. This version includes just a couple of very minor features and some minor bug fixes. For details regarding installation, setup, and general use, see Documentation. Note: If you were using a previous version, you will probably want to copy over the following user settings files: GW2PAO.DungeonSettings.xml GW2PAO.EventSettings.xml GW2PAO.WvWSettings.xml GW2PAO.ZoneCompletionSettings.xml New FeaturesAdded new "No...WallSwitch: WallSwitch 1.2.5: Version 1.2.5 Changes: Added support for sequential order in collage mode. Added option to display multiple images per switch in collage mode. Fixed bug where border width wasn't being loaded properly, and was reverting to default values. Fixed bug where sequential order was repeating images on multiple monitors. Decreased likelihood of random images being repeated.OpenCppCoverage: OpenCppCoverage 0.9.1: - Add Jenkins support. - Command line argument can be placed inside a config file. If you do not have Visual Studio C++ 2013 you need to download redistributable packages: http://www.microsoft.com/en-us/download/details.aspx?id=40784Easy Backup Windows Service: Release 2.0 with CU: Fix log error when "To" directory not exist in fyle system. Force run program as administrator by default. Add 'everyday' schedule element. Update solution to VS 2013.Easy Backup Application: Release 2.0 with CU: Fix log error when "To" directory not exist in fyle system. Fix app location initialization. Force run program as administrator by default. Update solution to VS 2013.TEBookConverter: 1.5: Added: Turkish and French translations Added: A few interface changes Removed: SkinDynamulet: Dynamulet v0.1: DynamoDB Transaction Server v0.1Console parallel nunit tests runner: ConsoleUnitTestsRunner 1.03: bugfixingFluentx: Fluentx v1.5.3: Added few more extension methods.fastJSON: v2.1.2: 2.1.2 - bug fix circular referencesJPush.NET: JPush Server SDK 1.2.1 (For JPush V3): Assembly: 1.2.1.24728 JPush REST API Version: v3 JPush Documentation Reference .NET framework: v4.0 or above. Sample: class: JPushClientV3 2014 Augest 15th.SEToolbox: SEToolbox 01.043.008 Release 1: Changed ship/station names to use new DisplayName instead of Beacon/Antenna. Fixed issue with updated SE binaries 01.043.018 using new Voxel Material definitions.Google .Net API: Drive.Sample: Google .NET Client API – Drive.SampleInstructions for the Google .NET Client API – Drive.Sample</h2> http://code.google.com/p/google-api-dotnet-client/source/browse/?repo=samples#hg%2FDrive.SampleBrowse Source, or main file http://code.google.com/p/google-api-dotnet-client/source/browse/Drive.Sample/Program.cs?repo=samplesProgram.cs <h3>1. Checkout Instructions</h3> <p><b>Prerequisites:</b> Install Visual Studio, and <a href="http://mercurial.selenic.com/">Mercurial</a>.</p> ...FineUI - jQuery / ExtJS based ASP.NET Controls: FineUI v4.1.1: -??Form??????????????（???-5929）。 -?TemplateField??ExpandOnDoubleClick、ExpandOnEnter、ExpandToSelectRow????（LZOM-5932）。 -BodyPadding???????，??“5”“5 10”，???????????“5px”“5px 10px”。 -??TriggerBox?EnableEdit=false????，??????????????（Jango_Jing-5450）。 -???????????DataKeyNames???????????（yygy-6002）。 -????????????????????????（Gnid-6018）。 -??PageManager???AutoSizePanelID????，??????????????????（yygy-6008）。 -?FState???????????????，????????????????（????-5925）。 -??????OnClientClick???return?????????（FineU...DNN CMS Platform: 07.03.02: Major Highlights Fixed backwards compatibility issue with 3rd party control panels Fixed issue in the drag and drop functionality of the File Uploader in IE 11 and Safari Fixed issue where users were able to create pages with the same name Fixed issue that affected older versions of DNN that do not include the maxAllowedContentLength during upgrade Fixed issue that stopped some skins from being upgraded to newer versions Fixed issue that randomly showed an unexpected error during us...WordMat: WordMat for Mac: WordMat for Mac has a few limitations compared to the Windows version - Graph is not supported (Gnuplot, GeoGebra and Excel works) - Units are not supported yet (Coming up) The Mac version is yet as tested as the windows version.MFCMAPI: August 2014 Release: Build: 15.0.0.1042 Full release notes at SGriffin's blog. If you just want to run the MFCMAPI or MrMAPI, get the executables. If you want to debug them, get the symbol files and the source. The 64 bit builds will only work on a machine with Outlook 2010/2013 64 bit installed. All other machines should use the 32 bit builds, regardless of the operating system. Facebook BadgeEWSEditor: EwsEditor 1.10 Release: • Export and import of items as a full fidelity steam works - without proxy classes! - I used raw EWS POSTs. • Turned off word wrap for EWS request field in EWS POST windows. • Several windows with scrolling texts boxes were limiting content to 32k - I removed this restriction. • Split server timezone info off to separate menu item from the timezone info windows so that the timezone info window could be used without logging into a mailbox. • Lots of updates to the TimeZone window. • UserAgen...New Projectsballmon: ballmonExchange Database Recovery With and Without Log Files is Possible: This segments giving an overview of Exchange Server transaction log files. It describes process how users can recover their database with & without log filesFabs.Net: Ego tatmini ve gelisme amaçli yaptigim bir projedir.JacoChat: JacoChat is a simple chatting interface that uses my personal webserver as a "wall" for people to chat on.ManagedWin32: ManagedWin32 is a library that exposes the Win32 API to .NET applications.Open XML Extensions: The project provides additions to the Open XML SDK and related projects (e.g., PowerTools for Open XML), starting with MemoryStreams for Open XML Documents.orntic: Project for insurace companyTBOX: The Treasure Box Library: TBOX is a mutli-platform c library for unix, windows, mac, ios, android, etc. It includes asio, stream, container, algorithm, xml and other library modules.WeatherTS: Typescript weather application.?????@/????: ??????????????:????,????,????,???????,????????,??????:????????,?????! ?????????: ????????????????????,????????:??、??、???,?????????????????????! ????-??: ??????????????，????，???????????????。

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• #OOW 2012 : IaaS, Private Cloud, Multitenant Database, and X3H2M2

  - by Eric Bezille

  The title of this post is a summary of the 4 announcements made by Larry Ellison today, during the opening session of Oracle Open World 2012... To know what's behind X3H2M2, you will have to wait a little, as I will go in order, beginning with the IaaS - Infrastructure as a Service - announcement. Oracle IaaS goes Public... and Private... Starting in 2004 with Fusion development, Oracle Cloud was launch last year to provide not only SaaS Application, based on standard development, but also the underlying PaaS, required to build the specifics, and required interconnections between applications, in and outside of the Cloud. Still, to cover the end-to-end Cloud  Services spectrum, we had to provide an Infrastructure as a Service, leveraging our Servers, Storage, OS, and Virtualization Technologies, all "Engineered Together". This Cloud Infrastructure, was already available for our customers to build rapidly their own Private Cloud either on SPARC/Solaris or x86/Linux... The second announcement made today bring that proposition a big step further : for cautious customers (like Banks, or sensible industries) who would like to benefits from the Cloud value of "as a Service", but don't want their Data out in the Cloud... We propose to them to operate the same systems, Exadata, Exalogic & SuperCluster, that are providing our Public Cloud Infrastructure, behind their firewall, in a Private Cloud model. Oracle 12c Multitenant Database This is also a major announcement made today, on what's coming with Oracle Database 12c : the ability to consolidate multiple databases with no extra additional  cost especially in terms of memory needed on the server node, which is often THE consolidation limiting factor. The principle could be compare to Solaris Zones, where, you will have a Database Container, who is "owning" the memory and Database background processes, and "Pluggable" Database in this Database Container. This particular feature is a strong compelling event to evaluate rapidly Oracle Database 12c once it will be available, as this is major step forward into true Database consolidation with Multitenancy on a shared (optimized) infrastructure. X3H2M2, enabling the new Exadata X3 in-Memory Database Here we are :  X3H2M2 stands for X3 (the new version of Exadata announced also today) Heuristic Hierarchical Mass Memory, providing the capability to keep most if not all the Data in the memory cache hierarchy. Of course, this is the major software enhancement of the new X3 Exadata machine, but as this is a software, our current customers would be able to benefit from it on their existing systems by upgrading to the new release. But that' not the only thing that we did with X3, at the same time we have upgraded everything : the CPUs, adding more cores per server node (16 vs. 12, with the arrival of Intel E5 / Sandy Bridge), the memory with 512GB memory as well per node,  and the new Flash Fire card, bringing now up to 22 TB of Flash cache. All of this 4TB of RAM + 22TB of Flash being use cleverly not only for read but also for write by the X3H2M2 algorithm... making a very big difference compare to traditional storage flash extension. But what does those extra performances brings to you on an already very efficient system: double your performances compare to the fastest storage array on the market today (including flash) and divide you storage price x10 at the same time... Something to consider closely this days... Especially that we also announced the availability of a new Exadata X3-2 8th rack : a good starting point. As you have seen a major opening for this year again with true innovation. But that was not the only thing that we saw today, as before Larry's talk, Fujitsu did introduce more in deep the up coming new SPARC processor, that they are co-developing with us. And as such Andrew Mendelsohn - Senior Vice President Database Server Technologies came on stage to explain that the next step after I/O optimization for Database with Exadata, was to accelerate the Database at execution level by bringing functions in the SPARC processor silicium. All in all, to process more and more Data... The big theme of the day... and of the Oracle User Groups Conferences that were also happening today and where I had the opportunity to attend some interesting sessions on practical use cases of Big Data one in Finances and Fraud profiling and the other one on practical deployment of Oracle Exalytics for Data Analytics. In conclusion, one picture to try to size Oracle Open World ... and you can understand why, with such a rich content... and this only the first day !

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• ANTS CLR and Memory Profiler In Depth Review (Part 2 of 2 &ndash; Memory Profiler)

  - by ToStringTheory

  One of the things that people might not know about me, is my obsession to make my code as efficient as possible. Many people might not realize how much of a task or undertaking that this might be, but it is surely a task as monumental as climbing Mount Everest, except this time it is a challenge for the mind… In trying to make code efficient, there are many different factors that play a part – size of project or solution, tiers, language used, experience and training of the programmer, technologies used, maintainability of the code – the list can go on for quite some time. I spend quite a bit of time when developing trying to determine what is the best way to implement a feature to accomplish the efficiency that I look to achieve. One program that I have recently come to learn about – Red Gate ANTS Performance (CLR) and Memory profiler gives me tools to accomplish that job more efficiently as well. In this review, I am going to cover some of the features of the ANTS memory profiler set by compiling some hideous example code to test against. Notice As a member of the Geeks With Blogs Influencers program, one of the perks is the ability to review products, in exchange for a free license to the program. I have not let this affect my opinions of the product in any way, and Red Gate nor Geeks With Blogs has tried to influence my opinion regarding this product in any way. Introduction – Part 2 In my last post, I reviewed the feature packed Red Gate ANTS Performance Profiler.  Separate from the Red Gate Performance Profiler is the Red Gate ANTS Memory Profiler – a simple, easy to use utility for checking how your application is handling memory management…  A tool that I wish I had had many times in the past.  This post will be focusing on the ANTS Memory Profiler and its tool set. The memory profiler has a large assortment of features just like the Performance Profiler, with the new session looking nearly exactly alike: ANTS Memory Profiler Memory profiling is not something that I have to do very often…  In the past, the few cases I’ve had to find a memory leak in an application I have usually just had to trace the code of the operations being performed to look for oddities…  Sadly, I have come across more undisposed/non-using’ed IDisposable objects, usually from ADO.Net than I would like to ever see.  Support is not fun, however using ANTS Memory Profiler makes this task easier.  For this round of testing, I am going to use the same code from my previous example, using the WPF application. This time, I will choose the ‘Profile Memory’ option from the ANTS menu in Visual Studio, which launches the solution in its currently configured state/start-up project, and then launches the ANTS Memory Profiler to help.  It prepopulates all of the fields with the current project information, and all I have to do is select the ‘Start Profiling’ option. When the window comes up, it is actually quite barren, just giving ideas on how to work the profiler.  You start by getting to the point in your application that you want to profile, and then taking a ‘Memory Snapshot’.  This performs a full garbage collection, and snapshots the managed heap.  Using the same WPF app as before, I will go ahead and take a snapshot now. As you can see, ANTS is already giving me lots of information regarding the snapshot, however this is just a snapshot.  The whole point of the profiler is to perform an action, usually one where a memory problem is being noticed, and then take another snapshot and perform a diff between them to see what has changed.  I am going to go ahead and generate 5000 primes, and then take another snapshot: As you can see, ANTS is already giving me a lot of new information about this snapshot compared to the last.  Information such as difference in memory usage, fragmentation, class usage, etc…  If you take more snapshots, you can use the dropdown at the top to set your actual comparison snapshots. If you beneath the timeline, you will see a breadcrumb trail showing how best to approach profiling memory using ANTS.  When you first do the comparison, you start on the Summary screen.  You can either use the charts at the bottom, or switch to the class list screen to get to the next step.  Here is the class list screen: As you can see, it lists information about all of the instances between the snapshots, as well as at the bottom giving you a way to filter by telling ANTS what your problem is.  I am going to go ahead and select the Int16[] to look at the Instance Categorizer Using the instance categorizer, you can travel backwards to see where all of the instances are coming from.  It may be hard to see in this image, but hopefully the lightbox (click on it) will help: I can see that all of these instances are rooted to the application through the UI TextBlock control.  This image will probably be even harder to see, however using the ‘Instance Retention Graph’, you can trace an objects memory inheritance up the chain to see its roots as well.  This is a simple example, as this is simply a known element.  Usually you would be profiling an actual problem, and comparing those differences.  I know in the past, I have spotted a problem where a new context was created per page load, and it was rooted into the application through an event.  As the application began to grow, performance and reliability problems started to emerge.  A tool like this would have been a great way to identify the problem quickly. Overview Overall, I think that the Red Gate ANTS Memory Profiler is a great utility for debugging those pesky leaks.  3 Biggest Pros: Easy to use interface with lots of options for configuring profiling session Intuitive and helpful interface for drilling down from summary, to instance, to root graphs ANTS provides an API for controlling the profiler. Not many options, but still helpful. 2 Biggest Cons: Inability to automatically snapshot the memory by interval Lack of complete integration with Visual Studio via an extension panel Ratings Ease of Use (9/10) – I really do believe that they have brought simplicity to the once difficult task of memory profiling.  I especially liked how it stepped you further into the drilldown by directing you towards the best options. Effectiveness (10/10) – I believe that the profiler does EXACTLY what it purports to do.  Features (7/10) – A really great set of features all around in the application, however, I would like to see some ability for automatically triggering snapshots based on intervals or framework level items such as events. Customer Service (10/10) – My entire experience with Red Gate personnel has been nothing but good.  their people are friendly, helpful, and happy! UI / UX (9/10) – The interface is very easy to get around, and all of the options are easy to find.  With a little bit of poking around, you’ll be optimizing Hello World in no time flat! Overall (9/10) – Overall, I am happy with the Memory Profiler and its features, as well as with the service I received when working with the Red Gate personnel.  Thank you for reading up to here, or skipping ahead – I told you it would be shorter!  Please, if you do try the product, drop me a message and let me know what you think!  I would love to hear any opinions you may have on the product. Code Feel free to download the code I used above – download via DropBox

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• Cocos2d: Moving background on update: offsett issue

  - by mm24

  working with Objective C, iOS and Cocos2d I am developing a vertical scrolling shooter game for iPhone (retina display models with 640 width x 960 height pixel resolution). My basic algorithm works as following: I create two instances of an image that has exactly 640 width x 960 height pixel of resolution, which we will call imageA and imageB I then set the two imags with exactly 480.0f of offset from each other, as the screenSize of a CCScene is set by default to 480.0f. At each update method call I move the two images by the same value. I make sure that their offsett stays to 480.0f However when running the game I see a 1 pixel height line between the two images. This literally bugs me and would like to adjust this. What am I doing wrong? This is a zoom in on the background when the "offsett line" is visible. The white line you can see divides the two background images and is not meant to exist as both images are completely black :): If I change the yPositionOfSecondElement value to 479.0f until the first loop the two images overlap correctly, but as soon as the loop starts the two images starts having an offsett of -1.0f. Here is the initialization code: -(void) init { //... screenHeight = 480.0f; yPositionOfSecondElement= screenHeight;//I tried subtracting an offsett of -1 but eventually the image would go wrong again yPositionOfFirstElement = 0.0f; loopedBackgroundImageInstanceA = [BackgroundLoopedImage loopImageForLevel:levelName]; loopedBackgroundImageInstanceA.anchorPoint = CGPointMake(0.5f, 0.0f); loopedBackgroundImageInstanceA.position = CGPointMake(160.0f, yPositionOfFirstElement); [node addChild:loopedBackgroundImageInstanceA z:zLevelBackground]; //loopedBackgroundImageInstanceA.color= ccRED; loopedBackgroundImageInstanceB = [BackgroundLoopedImage loopImageForLevel:levelName]; loopedBackgroundImageInstanceB.anchorPoint = CGPointMake(0.5f, 0.0f); loopedBackgroundImageInstanceB.position = CGPointMake(160.0f, yPositionOfSecondElement); [node addChild:loopedBackgroundImageInstanceB z:zLevelBackground]; //.... } And here is the move code called at each update: -(void) moveBackgroundSprites:(BackgroundLoopedImage*)imageA :(BackgroundLoopedImage*)imageB :(ccTime)delta { isEligibleToMove=false; //This is done to avoid rounding errors float yStep = delta * [GameController sharedGameController].currentBackgroundSpeed; NSString* formattedNumber = [NSString stringWithFormat:@"%.02f", yStep]; yStep = atof([formattedNumber UTF8String]); //First should adjust position of images [self adjustPosition:imageA :imageB]; //The can get the actual image position CGPoint posA = imageA.position; CGPoint posB = imageB.position; //Here could verify if the checksum is equal to the required difference (should be 479.0f) if (![self verifyCheckSum:posA :posB]) { CCLOG(@"does not comply A"); } //At this stage can compute the hypotetical new position CGPoint newPosA = CGPointMake(posA.x, posA.y - yStep); CGPoint newPosB = CGPointMake(posB.x, posB.y - yStep); // Reposition stripes when they're out of bounds if (newPosA.y <= -yPositionOfSecondElement) { newPosA.y = yPositionOfSecondElement; [imageA shuffle]; if (timeElapsed>=endTime && hasReachedEndLevel==FALSE) { hasReachedEndLevel=TRUE; shouldMoveImageEnd=TRUE; } } else if (newPosB.y <= -yPositionOfSecondElement) { newPosB.y = yPositionOfSecondElement; [imageB shuffle]; if (timeElapsed>=endTime && hasReachedEndLevel==FALSE) { hasReachedEndLevel=TRUE; shouldMoveImageEnd=TRUE; } } //Here should verify that the check sum is equal to 479.0f if (![self verifyCheckSum:posA :posB]) { CCLOG(@"does not comply B"); } imageA.position = newPosA; imageB.position = newPosB; //Here could verify that the check sum is equal to 479.0f if (![self verifyCheckSum:posA :posB]) { CCLOG(@"does not comply C"); } isEligibleToMove=true; } -(BOOL) verifyCheckSum:(CGPoint)posA :(CGPoint)posB { BOOL comply = false; float sum = 0.0f; if (posA.y > posB.y) { sum = posA.y - posB.y; } else if (posB.y > posA.y){ sum = posB.y - posA.y; } else{ return false; } if (sum!=yPositionOfSecondElement) { comply= false; } else{ comply=true; } return comply; } And here is what happens on the update: if(shouldMoveImageA && shouldMoveImageB) { if (isEligibleToMove) { [self moveBackgroundSprites:loopedBackgroundImageInstanceA :loopedBackgroundImageInstanceB :delta]; } Forget about shouldMoveImageA and shouldMoveImageB, this is just for when the background reaches the end of level, this works.

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• How do I make A* check all diagonal and orthogonal directions?

  - by Munezane

  I'm making a turn-based tactical game and I'm trying to implement the A* algorithm. I've been following a tutorial and got to this point, but my characters can't move diagonally up and left. Can anyone help me with this? The return x and y are int pointers which the characters are using to move towards the target. void level::aStar(int startx, int starty, int targetx, int targety, int* returnx, int* returny) { aStarGridSquare* currentSquare = new aStarGridSquare(); aStarGridSquare* startSquare = new aStarGridSquare(); aStarGridSquare* targetSquare = new aStarGridSquare(); aStarGridSquare* adjacentSquare = new aStarGridSquare(); aStarOpenList.clear(); for(unsigned int i=0; i<aStarGridSquareList.size(); i++) { aStarGridSquareList[i]->open=false; aStarGridSquareList[i]->closed=false; } startSquare=getaStarGridSquare(startx, starty); targetSquare=getaStarGridSquare(targetx, targety); if(startSquare==targetSquare) { *returnx=startx; *returny=starty; return; } startSquare->CostFromStart=0; startSquare->CostToTraverse=0; startSquare->parent = NULL; currentSquare=startSquare; aStarOpenList.push_back(currentSquare); while(currentSquare!=targetSquare && aStarOpenList.size()>0) { //unsigned int totalCostEstimate=aStarOpenList[0]->TotalCostEstimate; //currentSquare=aStarOpenList[0]; for(unsigned int i=0; i<aStarOpenList.size(); i++) { if(aStarOpenList.size()>1) { for(unsigned int j=1; j<aStarOpenList.size()-1; j++) { if(aStarOpenList[i]->TotalCostEstimate<aStarOpenList[j]->TotalCostEstimate) { currentSquare=aStarOpenList[i]; } else { currentSquare=aStarOpenList[j]; } } } else { currentSquare = aStarOpenList[i]; } } currentSquare->closed=true; currentSquare->open=false; for(unsigned int i=0; i<aStarOpenList.size(); i++) { if(aStarOpenList[i]==currentSquare) { aStarOpenList.erase(aStarOpenList.begin()+i); } } for(unsigned int i = currentSquare->blocky - 32; i <= currentSquare->blocky + 32; i+=32) { for(unsigned int j = currentSquare->blockx - 32; j<= currentSquare->blockx + 32; j+=32) { adjacentSquare=getaStarGridSquare(j/32, i/32); if(adjacentSquare!=NULL) { if(adjacentSquare->blocked==false && adjacentSquare->closed==false) { if(adjacentSquare->open==false) { adjacentSquare->parent=currentSquare; if(currentSquare->parent!=NULL) { currentSquare->CostFromStart = currentSquare->parent->CostFromStart + currentSquare->CostToTraverse + startSquare->CostFromStart; } else { currentSquare->CostFromStart=0; } adjacentSquare->CostFromStart =currentSquare->CostFromStart + adjacentSquare->CostToTraverse;// adjacentSquare->parent->CostFromStart + adjacentSquare->CostToTraverse; //currentSquare->CostToEndEstimate = abs(currentSquare->blockx - targetSquare->blockx) + abs(currentSquare->blocky - targetSquare->blocky); //currentSquare->TotalCostEstimate = currentSquare->CostFromStart + currentSquare->CostToEndEstimate; adjacentSquare->open = true; adjacentSquare->CostToEndEstimate=abs(adjacentSquare->blockx- targetSquare->blockx) + abs(adjacentSquare->blocky-targetSquare->blocky); adjacentSquare->TotalCostEstimate = adjacentSquare->CostFromStart+adjacentSquare->CostToEndEstimate; //adjacentSquare->open=true;*/ aStarOpenList.push_back(adjacentSquare); } else { if(adjacentSquare->parent->CostFromStart > currentSquare->CostFromStart) { adjacentSquare->parent=currentSquare; if(currentSquare->parent!=NULL) { currentSquare->CostFromStart = currentSquare->parent->CostFromStart + currentSquare->CostToTraverse + startSquare->CostFromStart; } else { currentSquare->CostFromStart=0; } adjacentSquare->CostFromStart =currentSquare->CostFromStart + adjacentSquare->CostToTraverse;// adjacentSquare->parent->CostFromStart + adjacentSquare->CostToTraverse; //currentSquare->CostToEndEstimate = abs(currentSquare->blockx - targetSquare->blockx) + abs(currentSquare->blocky - targetSquare->blocky); //currentSquare->TotalCostEstimate = currentSquare->CostFromStart + currentSquare->CostToEndEstimate; adjacentSquare->CostFromStart = adjacentSquare->parent->CostFromStart + adjacentSquare->CostToTraverse; adjacentSquare->CostToEndEstimate=abs(adjacentSquare->blockx - targetSquare->blockx) + abs(adjacentSquare->blocky - targetSquare->blocky); adjacentSquare->TotalCostEstimate = adjacentSquare->CostFromStart+adjacentSquare->CostToEndEstimate; } } } } } } } if(aStarOpenList.size()==0)//if empty { *returnx =startx; *returny =starty; return; } else { for(unsigned int i=0; i< aStarOpenList.size(); i++) { if(currentSquare->parent==NULL) { //int tempX = targetSquare->blockx; //int tempY = targetSquare->blocky; *returnx=targetSquare->blockx; *returny=targetSquare->blocky; break; } else { currentSquare=currentSquare->parent; } } } }

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• Contricted A* problem

  - by Ragekit

  I've got a little problem with an A* algorithm that I need to constrict a little bit. Basically : I use an A* to find the shortest path between 2 randomly placed room in 3D space, and then build a corridor between them. The problem I found is that sometimes it makes chimney like corridors that are not ideal, so I constrict the A* so that if the last movement was up or down, you go sideways. Everything is fine, but in some corner cases, it fails to find a path (when there is obviously one). Like here between the blue and red dot : (i'm in unity btw, but i don't think it matters) Here is the code of the actual A* (a bit long, and some redundency) while(current != goal) { //add stair up / stair down foreach(Node<GridUnit> test in current.Neighbors) { if(!test.Data.empty && test != goal) continue; //bug at arrival; if(test == goal && penul !=null) { Vector3 currentDiff = current.Data.bounds.center - test.Data.bounds.center; if(!Mathf.Approximately(currentDiff.y,0)) { //wanna drop on the last if(!coplanar(test.Data.bounds.center,current.Data.bounds.center,current.Data.parentUnit.bounds.center,to.Data.bounds.center)) { continue; } else { if(Mathf.Approximately(to.Data.bounds.center.x, current.Data.parentUnit.bounds.center.x) && Mathf.Approximately(to.Data.bounds.center.z, current.Data.parentUnit.bounds.center.z)) { continue; } } } } if(current.Data.parentUnit != null) { Vector3 previousDiff = current.Data.parentUnit.bounds.center - current.Data.bounds.center; Vector3 currentDiff = current.Data.bounds.center - test.Data.bounds.center; if(!Mathf.Approximately(previousDiff.y,0)) { if(!Mathf.Approximately(currentDiff.y,0)) { //you wanna drop now : continue; } if(current.Data.parentUnit.parentUnit != null) { if(!coplanar(test.Data.bounds.center,current.Data.bounds.center,current.Data.parentUnit.bounds.center,current.Data.parentUnit.parentUnit.bounds.center)) { continue; }else { if(Mathf.Approximately(test.Data.bounds.center.x, current.Data.parentUnit.parentUnit.bounds.center.x) && Mathf.Approximately(test.Data.bounds.center.z, current.Data.parentUnit.parentUnit.bounds.center.z)) { continue; } } } } } g = current.Data.g + HEURISTIC(current.Data,test.Data); h = HEURISTIC(test.Data,goal.Data); f = g + h; if(open.Contains(test) || closed.Contains(test)) { if(test.Data.f > f) { //found a shorter path going passing through that point test.Data.f = f; test.Data.g = g; test.Data.h = h; test.Data.parentUnit = current.Data; } } else { //jamais rencontré test.Data.f = f; test.Data.h = h; test.Data.g = g; test.Data.parentUnit = current.Data; open.Add(test); } } closed.Add (current); if(open.Count == 0) { Debug.Log("nothingfound"); //nothing more to test no path found, stay to from; List<GridUnit> r = new List<GridUnit>(); r.Add(from.Data); return r; } //sort open from small to biggest travel cost open.Sort(delegate(Node<GridUnit> x, Node<GridUnit> y) { return (int)(x.Data.f-y.Data.f); }); //get the smallest travel cost node; Node<GridUnit> smallest = open[0]; current = smallest; open.RemoveAt(0); } //build the path going backward; List<GridUnit> ret = new List<GridUnit>(); if(penul != null) { ret.Insert(0,to.Data); } GridUnit cur = goal.Data; ret.Insert(0,cur); do{ cur = cur.parentUnit; ret.Insert(0,cur); } while(cur != from.Data); return ret; You see at the start of the foreach i constrict the A* like i said. If you have any insight it would be cool. Thanks

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• Convert Java program to C

  - by imicrothinking

  I need a bit of guidance with writing a C program...a bit of quick background as to my level, I've programmed in Java previously, but this is my first time programming in C, and we've been tasked to translate a word count program from Java to C that consists of the following: Read a file from memory Count the words in the file For each occurrence of a unique word, keep a word counter variable Print out the top ten most frequent words and their corresponding occurrences Here's the source program in Java: package lab0; import java.io.File; import java.io.FileReader; import java.util.ArrayList; import java.util.Calendar; import java.util.Collections; public class WordCount { private ArrayList<WordCountNode> outputlist = null; public WordCount(){ this.outputlist = new ArrayList<WordCountNode>(); } /** * Read the file into memory. * * @param filename name of the file. * @return content of the file. * @throws Exception if the file is too large or other file related exception. */ public char[] readFile(String filename) throws Exception{ char [] result = null; File file = new File(filename); long size = file.length(); if (size > Integer.MAX_VALUE){ throw new Exception("File is too large"); } result = new char[(int)size]; FileReader reader = new FileReader(file); int len, offset = 0, size2read = (int)size; while(size2read > 0){ len = reader.read(result, offset, size2read); if(len == -1) break; size2read -= len; offset += len; } return result; } /** * Make article word by word. * * @param article the content of file to be counted. * @return string contains only letters and "'". */ private enum SPLIT_STATE {IN_WORD, NOT_IN_WORD}; /** * Go through article, find all the words and add to output list * with their count. * * @param article the content of the file to be counted. * @return words in the file and their counts. */ public ArrayList<WordCountNode> countWords(char[] article){ SPLIT_STATE state = SPLIT_STATE.NOT_IN_WORD; if(null == article) return null; char curr_ltr; int curr_start = 0; for(int i = 0; i < article.length; i++){ curr_ltr = Character.toUpperCase( article[i]); if(state == SPLIT_STATE.IN_WORD){ article[i] = curr_ltr; if ((curr_ltr < 'A' || curr_ltr > 'Z') && curr_ltr != '\'') { article[i] = ' '; //printf("\nthe word is %s\n\n",curr_start); if(i - curr_start < 0){ System.out.println("i = " + i + " curr_start = " + curr_start); } addWord(new String(article, curr_start, i-curr_start)); state = SPLIT_STATE.NOT_IN_WORD; } }else{ if (curr_ltr >= 'A' && curr_ltr <= 'Z') { curr_start = i; article[i] = curr_ltr; state = SPLIT_STATE.IN_WORD; } } } return outputlist; } /** * Add the word to output list. */ public void addWord(String word){ int pos = dobsearch(word); if(pos >= outputlist.size()){ outputlist.add(new WordCountNode(1L, word)); }else{ WordCountNode tmp = outputlist.get(pos); if(tmp.getWord().compareTo(word) == 0){ tmp.setCount(tmp.getCount() + 1); }else{ outputlist.add(pos, new WordCountNode(1L, word)); } } } /** * Search the output list and return the position to put word. * @param word is the word to be put into output list. * @return position in the output list to insert the word. */ public int dobsearch(String word){ int cmp, high = outputlist.size(), low = -1, next; // Binary search the array to find the key while (high - low > 1) { next = (high + low) / 2; // all in upper case cmp = word.compareTo((outputlist.get(next)).getWord()); if (cmp == 0) return next; else if (cmp < 0) high = next; else low = next; } return high; } public static void main(String args[]){ // handle input if (args.length == 0){ System.out.println("USAGE: WordCount <filename> [Top # of results to display]\n"); System.exit(1); } String filename = args[0]; int dispnum; try{ dispnum = Integer.parseInt(args[1]); }catch(Exception e){ dispnum = 10; } long start_time = Calendar.getInstance().getTimeInMillis(); WordCount wordcount = new WordCount(); System.out.println("Wordcount: Running..."); // read file char[] input = null; try { input = wordcount.readFile(filename); } catch (Exception e) { // TODO Auto-generated catch block e.printStackTrace(); System.exit(1); } // count all word ArrayList<WordCountNode> result = wordcount.countWords(input); long end_time = Calendar.getInstance().getTimeInMillis(); System.out.println("wordcount: completed " + (end_time - start_time)/1000000 + "." + (end_time - start_time)%1000000 + "(s)"); System.out.println("wordsort: running ..."); start_time = Calendar.getInstance().getTimeInMillis(); Collections.sort(result); end_time = Calendar.getInstance().getTimeInMillis(); System.out.println("wordsort: completed " + (end_time - start_time)/1000000 + "." + (end_time - start_time)%1000000 + "(s)"); Collections.reverse(result); System.out.println("\nresults (TOP "+ dispnum +" from "+ result.size() +"):\n" ); // print out result String str ; for (int i = 0; i < result.size() && i < dispnum; i++){ if(result.get(i).getWord().length() > 15) str = result.get(i).getWord().substring(0, 14); else str = result.get(i).getWord(); System.out.println(str + " - " + result.get(i).getCount()); } } public class WordCountNode implements Comparable{ private String word; private long count; public WordCountNode(long count, String word){ this.count = count; this.word = word; } public String getWord() { return word; } public void setWord(String word) { this.word = word; } public long getCount() { return count; } public void setCount(long count) { this.count = count; } public int compareTo(Object arg0) { // TODO Auto-generated method stub WordCountNode obj = (WordCountNode)arg0; if( count - obj.getCount() < 0) return -1; else if( count - obj.getCount() == 0) return 0; else return 1; } } } Here's my attempt (so far) in C: #include <stdio.h> #include <stdlib.h> #include <stdbool.h> #include <string.h> // Read in a file FILE *readFile (char filename[]) { FILE *inputFile; inputFile = fopen (filename, "r"); if (inputFile == NULL) { printf ("File could not be opened.\n"); exit (EXIT_FAILURE); } return inputFile; } // Return number of words in an array int wordCount (FILE *filePointer, char filename[]) {//, char *words[]) { // count words int count = 0; char temp; while ((temp = getc(filePointer)) != EOF) { //printf ("%c", temp); if ((temp == ' ' || temp == '\n') && (temp != '\'')) count++; } count += 1; // counting method uses space AFTER last character in word - the last space // of the last character isn't counted - off by one error // close file fclose (filePointer); return count; } // Print out the frequencies of the 10 most frequent words in the console int main (int argc, char *argv[]) { /* Step 1: Read in file and check for errors */ FILE *filePointer; filePointer = readFile (argv[1]); /* Step 2: Do a word count to prep for array size */ int count = wordCount (filePointer, argv[1]); printf ("Number of words is: %i\n", count); /* Step 3: Create a 2D array to store words in the file */ // open file to reset marker to beginning of file filePointer = fopen (argv[1], "r"); // store words in character array (each element in array = consecutive word) char allWords[count][100]; // 100 is an arbitrary size - max length of word int i,j; char temp; for (i = 0; i < count; i++) { for (j = 0; j < 100; j++) { // labels are used with goto statements, not loops in C temp = getc(filePointer); if ((temp == ' ' || temp == '\n' || temp == EOF) && (temp != '\'') ) { allWords[i][j] = '\0'; break; } else { allWords[i][j] = temp; } printf ("%c", allWords[i][j]); } printf ("\n"); } // close file fclose (filePointer); /* Step 4: Use a simple selection sort algorithm to sort 2D char array */ // PStep 1: Compare two char arrays, and if // (a) c1 > c2, return 2 // (b) c1 == c2, return 1 // (c) c1 < c2, return 0 qsort(allWords, count, sizeof(char[][]), pstrcmp); /* int k = 0, l = 0, m = 0; char currentMax, comparedElement; int max; // the largest element in the current 2D array int elementToSort = 0; // elementToSort determines the element to swap with starting from the left // Outer a iterates through number of swaps needed for (k = 0; k < count - 1; k++) { // times of swaps max = k; // max element set to k // Inner b iterates through successive elements to fish out the largest element for (m = k + 1; m < count - k; m++) { currentMax = allWords[k][l]; comparedElement = allWords[m][l]; // Inner c iterates through successive chars to set the max vars to the largest for (l = 0; (currentMax != '\0' || comparedElement != '\0'); l++) { if (currentMax > comparedElement) break; else if (currentMax < comparedElement) { max = m; currentMax = allWords[m][l]; break; } else if (currentMax == comparedElement) continue; } } // After max (count and string) is determined, perform swap with temp variable char swapTemp[1][20]; int y = 0; do { swapTemp[0][y] = allWords[elementToSort][y]; allWords[elementToSort][y] = allWords[max][y]; allWords[max][y] = swapTemp[0][y]; } while (swapTemp[0][y++] != '\0'); elementToSort++; } */ int a, b; for (a = 0; a < count; a++) { for (b = 0; (temp = allWords[a][b]) != '\0'; b++) { printf ("%c", temp); } printf ("\n"); } // Copy rows to different array and print results /* char arrayCopy [count][20]; int ac, ad; char tempa; for (ac = 0; ac < count; ac++) { for (ad = 0; (tempa = allWords[ac][ad]) != '\0'; ad++) { arrayCopy[ac][ad] = tempa; printf("%c", arrayCopy[ac][ad]); } printf("\n"); } */ /* Step 5: Create two additional arrays: (a) One in which each element contains unique words from char array (b) One which holds the count for the corresponding word in the other array */ /* Step 6: Sort the count array in decreasing order, and print the corresponding array element as well as word count in the console */ return 0; } // Perform housekeeping tasks like freeing up memory and closing file I'm really stuck on the selection sort algorithm. I'm currently using 2D arrays to represent strings, and that worked out fine, but when it came to sorting, using three level nested loops didn't seem to work, I tried to use qsort instead, but I don't fully understand that function as well. Constructive feedback and criticism greatly welcome (...and needed)!

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• Increasing efficiency of N-Body gravity simulation

  - by Postman

  I'm making a space exploration type game, it will have many planets and other objects that will all have realistic gravity. I currently have a system in place that works, but if the number of planets goes above 70, the FPS decreases an practically exponential rates. I'm making it in C# and XNA. My guess is that I should be able to do gravity calculations between 100 objects without this kind of strain, so clearly my method is not as efficient as it should be. I have two files, Gravity.cs and EntityEngine.cs. Gravity manages JUST the gravity calculations, EntityEngine creates an instance of Gravity and runs it, along with other entity related methods. EntityEngine.cs public void Update() { foreach (KeyValuePair<string, Entity> e in Entities) { e.Value.Update(); } gravity.Update(); } (Only relevant piece of code from EntityEngine, self explanatory. When an instance of Gravity is made in entityEngine, it passes itself (this) into it, so that gravity can have access to entityEngine.Entities (a dictionary of all planet objects)) Gravity.cs namespace ExplorationEngine { public class Gravity { private EntityEngine entityEngine; private Vector2 Force; private Vector2 VecForce; private float distance; private float mult; public Gravity(EntityEngine e) { entityEngine = e; } public void Update() { //First loop foreach (KeyValuePair<string, Entity> e in entityEngine.Entities) { //Reset the force vector Force = new Vector2(); //Second loop foreach (KeyValuePair<string, Entity> e2 in entityEngine.Entities) { //Make sure the second value is not the current value from the first loop if (e2.Value != e.Value ) { //Find the distance between the two objects. Because Fg = G * ((M1 * M2) / r^2), using Vector2.Distance() and then squaring it //is pointless and inefficient because distance uses a sqrt, squaring the result simple cancels that sqrt. distance = Vector2.DistanceSquared(e2.Value.Position, e.Value.Position); //This makes sure that two planets do not attract eachother if they are touching, completely unnecessary when I add collision, //For now it just makes it so that the planets are not glitchy, performance is not significantly improved by removing this IF if (Math.Sqrt(distance) > (e.Value.Texture.Width / 2 + e2.Value.Texture.Width / 2)) { //Calculate the magnitude of Fg (I'm using my own gravitational constant (G) for the sake of time (I know it's 1 at the moment, but I've been changing it) mult = 1.0f * ((e.Value.Mass * e2.Value.Mass) / distance); //Calculate the direction of the force, simply subtracting the positions and normalizing works, this fixes diagonal vectors //from having a larger value, and basically makes VecForce a direction. VecForce = e2.Value.Position - e.Value.Position; VecForce.Normalize(); //Add the vector for each planet in the second loop to a force var. Force = Vector2.Add(Force, VecForce * mult); //I have tried Force += VecForce * mult, and have not noticed much of an increase in speed. } } } //Add that force to the first loop's planet's position (later on I'll instead add to acceleration, to account for inertia) e.Value.Position += Force; } } } } I have used various tips (about gravity optimizing, not threading) from THIS question (that I made yesterday). I've made this gravity method (Gravity.Update) as efficient as I know how to make it. This O(N^2) algorithm still seems to be eating up all of my CPU power though. Here is a LINK (google drive, go to File download, keep .Exe with the content folder, you will need XNA Framework 4.0 Redist. if you don't already have it) to the current version of my game. Left click makes a planet, right click removes the last planet. Mouse moves the camera, scroll wheel zooms in and out. Watch the FPS and Planet Count to see what I mean about performance issues past 70 planets. (ALL 70 planets must be moving, I've had 100 stationary planets and only 5 or so moving ones while still having 300 fps, the issue arises when 70+ are moving around) After 70 planets are made, performance tanks exponentially. With < 70 planets, I get 330 fps (I have it capped at 300). At 90 planets, the FPS is about 2, more than that and it sticks around at 0 FPS. Strangely enough, when all planets are stationary, the FPS climbs back up to around 300, but as soon as something moves, it goes right back down to what it was, I have no systems in place to make this happen, it just does. I considered multithreading, but that previous question I asked taught me a thing or two, and I see now that that's not a viable option. I've also thought maybe I could do the calculations on my GPU instead, though I don't think it should be necessary. I also do not know how to do this, it is not a simple concept and I want to avoid it unless someone knows a really noob friendly simple way to do it that will work for an n-body gravity calculation. (I have an NVidia gtx 660) Lastly I've considered using a quadtree type system. (Barnes Hut simulation) I've been told (in the previous question) that this is a good method that is commonly used, and it seems logical and straightforward, however the implementation is way over my head and I haven't found a good tutorial for C# yet that explains it in a way I can understand, or uses code I can eventually figure out. So my question is this: How can I make my gravity method more efficient, allowing me to use more than 100 objects (I can render 1000 planets with constant 300+ FPS without gravity calculations), and if I can't do much to improve performance (including some kind of quadtree system), could I use my GPU to do the calculations?

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• Java EE 7 Survey Results!

  - by reza_rahman

  On November 8th, the Java EE EG posted a survey to gather broad community feedback on a number of critical open issues. For reference, you can find the original survey here. We kept the survey open for about three weeks until November 30th. To our delight, over 1100 developers took time out of their busy lives to let their voices be heard! The results of the survey were sent to the EG on December 12th. The subsequent EG discussion is available here. The exact summary sent to the EG is available here. We would like to take this opportunity to thank each and every one the individuals who took the survey. It is very appreciated, encouraging and worth it's weight in gold. In particular, I tried to capture just some of the high-quality, intelligent, thoughtful and professional comments in the summary to the EG. I highly encourage you to continue to stay involved, perhaps through the Adopt-a-JSR program. We would also like to sincerely thank java.net, JavaLobby, TSS and InfoQ for helping spread the word about the survey. Below is a brief summary of the results... APIs to Add to Java EE 7 Full/Web Profile The first question asked which of the four new candidate APIs (WebSocket, JSON-P, JBatch and JCache) should be added to the Java EE 7 Full and Web profile respectively. As the following graph shows, there was significant support for adding all the new APIs to the full profile: Support is relatively the weakest for Batch 1.0, but still good. A lot of folks saw WebSocket 1.0 as a critical technology with comments such as this one: "A modern web application needs Web Sockets as first class citizens" While it is clearly seen as being important, a number of commenters expressed dissatisfaction with the lack of a higher-level JSON data binding API as illustrated by this comment: "How come we don't have a Data Binding API for JSON" JCache was also seen as being very important as expressed with comments like: "JCache should really be that foundational technology on which other specs have no fear to depend on" The results for the Web Profile is not surprising. While there is strong support for adding WebSocket 1.0 and JSON-P 1.0 to the Web Profile, support for adding JCache 1.0 and Batch 1.0 is relatively weak. There was actually significant opposition to adding Batch 1. 0 (with 51.8% casting a 'No' vote). Enabling CDI by Default The second question asked was whether CDI should be enabled in Java EE environments by default. A significant majority of 73.3% developers supported enabling CDI, only 13.8% opposed. Comments such as these two reflect a strong general support for CDI as well as a desire for better Java EE alignment with CDI: "CDI makes Java EE quite valuable!" "Would prefer to unify EJB, CDI and JSF lifecycles" There is, however, a palpable concern around the performance impact of enabling CDI by default as exemplified by this comment: "Java EE projects in most cases use CDI, hence it is sensible to enable CDI by default when creating a Java EE application. However, there are several issues if CDI is enabled by default: scanning can be slow - not all libs use CDI (hence, scanning is not needed)" Another significant concern appears to be around backwards compatibility and conflict with other JSR 330 implementations like Spring: "I am leaning towards yes, however can easily imagine situations where errors would be caused by automatically activating CDI, especially in cases of backward compatibility where another DI engine (such as Spring and the like) happens to use the same mechanics to inject dependencies and in that case there would be an overlap in injections and probably an uncertain outcome" Some commenters such as this one attempt to suggest solutions to these potential issues: "If you have Spring in use and use javax.inject.Inject then you might get some unexpected behavior that could be equally confusing. I guess there will be a way to switch CDI off. I'm tempted to say yes but am cautious for this reason" Consistent Usage of @Inject The third question was around using CDI/JSR 330 @Inject consistently vs. allowing JSRs to create their own injection annotations. A slight majority of 53.3% developers supported using @Inject consistently across JSRs. 28.8% said using custom injection annotations is OK, while 18.0% were not sure. The vast majority of commenters were strongly supportive of CDI and general Java EE alignment with CDI as illistrated by these comments: "Dependency Injection should be standard from now on in EE. It should use CDI as that is the DI mechanism in EE and is quite powerful. Having a new JSR specific DI mechanism to deal with just means more reflection, more proxies. JSRs should also be constructed to allow some of their objects Injectable. @Inject @TransactionalCache or @Inject @JMXBean etc...they should define the annotations and stereotypes to make their code less procedural. Dog food it. If there is a shortcoming in CDI for a JSR fix it and we will all be grateful" "We're trying to make this a comprehensive platform, right? Injection should be a fundamental part of the platform; everything else should build on the same common infrastructure. Each-having-their-own is just a recipe for chaos and having to learn the same thing 10 different ways" Expanding the Use of @Stereotype The fourth question was about expanding CDI @Stereotype to cover annotations across Java EE beyond just CDI. A significant majority of 62.3% developers supported expanding the use of @Stereotype, only 13.3% opposed. A majority of commenters supported the idea as well as the theme of general CDI/Java EE alignment as expressed in these examples: "Just like defining new types for (compositions of) existing classes, stereotypes can help make software development easier" "This is especially important if many EJB services are decoupled from the EJB component model and can be applied via individual annotations to Java EE components. @Stateless is a nicely compact annotation. Code will not improve if that will have to be applied in the future as @Transactional, @Pooled, @Secured, @Singlethreaded, @...." Some, however, expressed concerns around increased complexity such as this commenter: "Could be very convenient, but I'm afraid if it wouldn't make some important class annotations less visible" Expanding Interceptor Use The final set of questions was about expanding interceptors further across Java EE... A very solid 96.3% of developers wanted to expand interceptor use to all Java EE components. 35.7% even wanted to expand interceptors to other Java EE managed classes. Most developers (54.9%) were not sure if there is any place that injection is supported that should not support interceptors. 32.8% thought any place that supports injection should also support interceptors. Only 12.2% were certain that there are places where injection should be supported but not interceptors. The comments reflected the diversity of opinions, generally supportive of interceptors: "I think interceptors are as fundamental as injection and should be available anywhere in the platform" "The whole usage of interceptors still needs to take hold in Java programming, but it is a powerful technology that needs some time in the Sun. Basically it should become part of Java SE, maybe the next step after lambas?" A distinct chain of thought separated interceptors from filters and listeners: "I think that the Servlet API already provides a rich set of possibilities to hook yourself into different Servlet container events. I don't find a need to 'pollute' the Servlet model with the Interceptors API"

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• Data Source Security Part 4

  - by Steve Felts

  So far, I have covered Client Identity and Oracle Proxy Session features, with WLS or database credentials.  This article will cover one more feature, Identify-based pooling.  Then, there is one more topic to cover - how these options play with transactions.Identity-based Connection Pooling An identity based pool creates a heterogeneous pool of connections.  This allows applications to use a JDBC connection with a specific DBMS credential by pooling physical connections with different DBMS credentials.  The DBMS credential is based on either the WebLogic user mapped to a database user or the database user directly, based on the “use database credentials” setting as described earlier. Using this feature enabled with “use database credentials” enabled seems to be what is proposed in the JDBC standard, basically a heterogeneous pool with users specified by getConnection(user, password). The allocation of connections is more complex if Enable Identity Based Connection Pooling attribute is enabled on the data source.  When an application requests a database connection, the WebLogic Server instance selects an existing physical connection or creates a new physical connection with requested DBMS identity. The following section provides information on how heterogeneous connections are created:1. At connection pool initialization, the physical JDBC connections based on the configured or default “initial capacity” are created with the configured default DBMS credential of the data source.2. An application tries to get a connection from a data source.3a. If “use database credentials” is not enabled, the user specified in getConnection is mapped to a DBMS credential, as described earlier.  If the credential map doesn’t have a matching user, the default DBMS credential is used from the datasource descriptor.3b. If “use database credentials” is enabled, the user and password specified in getConnection are used directly.4. The connection pool is searched for a connection with a matching DBMS credential.5. If a match is found, the connection is reserved and returned to the application.6. If no match is found, a connection is created or reused based on the maximum capacity of the pool: - If the maximum capacity has not been reached, a new connection is created with the DBMS credential, reserved, and returned to the application.- If the pool has reached maximum capacity, based on the least recently used (LRU) algorithm, a physical connection is selected from the pool and destroyed. A new connection is created with the DBMS credential, reserved, and returned to the application. It should be clear that finding a matching connection is more expensive than a homogeneous pool.  Destroying a connection and getting a new one is very expensive.  If you can use a normal homogeneous pool or one of the light-weight options (client identity or an Oracle proxy connection), those should be used instead of identity based pooling. Regardless of how physical connections are created, each physical connection in the pool has its own DBMS credential information maintained by the pool. Once a physical connection is reserved by the pool, it does not change its DBMS credential even if the current thread changes its WebLogic user credential and continues to use the same connection. To configure this feature, select Enable Identity Based Connection Pooling.  See http://docs.oracle.com/cd/E24329_01/apirefs.1211/e24401/taskhelp/jdbc/jdbc_datasources/EnableIdentityBasedConnectionPooling.html  "Enable identity-based connection pooling for a JDBC data source" in Oracle WebLogic Server Administration Console Help. You must make the following changes to use Logging Last Resource (LLR) transaction optimization with Identity-based Pooling to get around the problem that multiple users will be accessing the associated transaction table.- You must configure a custom schema for LLR using a fully qualified LLR table name. All LLR connections will then use the named schema rather than the default schema when accessing the LLR transaction table.  - Use database specific administration tools to grant permission to access the named LLR table to all users that could access this table via a global transaction. By default, the LLR table is created during boot by the user configured for the connection in the data source. In most cases, the database will only allow access to this user and not allow access to mapped users. Connections within Transactions Now that we have covered the behavior of all of these various options, it’s time to discuss the exception to all of the rules.  When you get a connection within a transaction, it is associated with the transaction context on a particular WLS instance. When getting a connection with a data source configured with non-XA LLR or 1PC (using the JTS driver) with global transactions, the first connection obtained within the transaction is returned on subsequent connection requests regardless of the values of username/password specified and independent of the associated proxy user session, if any. The connection must be shared among all users of the connection when using LLR or 1PC. For XA data sources, the first connection obtained within the global transaction is returned on subsequent connection requests within the application server, regardless of the values of username/password specified and independent of the associated proxy user session, if any.  The connection must be shared among all users of the connection within a global transaction within the application server/JVM.

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