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• PASS Summit 2011 &ndash; Part III

  - by Tara Kizer

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

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• Take Advantage of Oracle's Ongoing Assurance Effort!

  - by eric.maurice

  Hi, this is Eric Maurice again! A few years ago, I posted a blog entry, which discussed the psychology of patching. The point of this blog entry was that a natural tendency existed for systems and database administrators to be reluctant to apply patches, even security patches, because of the fear of "breaking" the system. Unfortunately, this belief in the principle "if it ain't broke, don't fix it!" creates significant risks for organizations. Running systems without applying the proper security patches can greatly compromise the security posture of the organization because the security controls available in the affected system may be compromised as a result of the existence of the unfixed vulnerabilities. As a result, Oracle continues to strongly recommend that customers apply all security fixes as soon as possible. Most recently, I have had a number of conversations with customers who questioned the need to upgrade their highly stable but otherwise unsupported Oracle systems. These customers wanted to know more about the kind of security risks they were exposed to, by running obsolete versions of Oracle software. As per Oracle Support Policies, Critical Patch Updates are produced for currently supported products. In other words, Critical Patch Updates are not created by Oracle for product versions that are no longer covered under the Premier Support or Extended Support phases of the Lifetime Support Policy. One statement used in each Critical Patch Update Advisory is particularly important: "We recommend that customers upgrade to a supported version of Oracle products in order to obtain patches. Unsupported products, releases and versions are not tested for the presence of vulnerabilities addressed by this Critical Patch Update. However, it is likely that earlier versions of affected releases are also affected by these vulnerabilities." The purpose of this warning is to inform Oracle customers that a number of the vulnerabilities fixed in each Critical Patch Update may affect older versions of a specific product line. In other words, each Critical Patch Update provides a number of fixes for currently supported versions of a given product line (this information is listed for each bug in the Risk Matrices of the Critical Patch Update Advisory), but the unsupported versions in the same product line, while they may be affected by the vulnerabilities, will not receive the fixes, and are therefore vulnerable to attacks. The risk assumed by organizations wishing to remain on unsupported versions is amplified by the behavior of malicious hackers, who typically will attempt to, and sometimes succeed in, reverse-engineering the content of vendors' security fixes. As a result, it is not uncommon for exploits to be published soon after Oracle discloses vulnerabilities with the release of a Critical Patch Update or Security Alert. Let's consider now the nature of the vulnerabilities that may exist in obsolete versions of Oracle software. A number of severe vulnerabilities have been fixed by Oracle over the years. While Oracle does not test unsupported products, releases and versions for the presence of vulnerabilities addressed by each Critical Patch Update, it should be assumed that a number of the vulnerabilities fixed with the Critical Patch Update program do exist in unsupported versions (regardless of the product considered). The most severe vulnerabilities fixed in past Critical Patch Updates may result in full compromise of the targeted systems, down to the OS level, by remote and unauthenticated users (these vulnerabilities receive a CVSS Base Score of 10.0) or almost as critically, may result in the compromise of the affected systems (without compromising the underlying OS) by a remote and unauthenticated users (these vulnerabilities receive a CVSS Base Score of 7.5). Such vulnerabilities may result in complete takeover of the targeted machine (for the CVSS 10.0), or may result in allowing the attacker the ability to create a denial of service against the affected system or even hijacking or stealing all the data hosted by the compromised system (for the CVSS 7.5). The bottom line is that organizations should assume the worst case: that the most critical vulnerabilities are present in their unsupported version; therefore, it is Oracle's recommendation that all organizations move to supported systems and apply security patches in a timely fashion. Organizations that currently run supported versions but may be late in their security patch release level can quickly catch up because most Critical Patch Updates are cumulative. With a few exceptions noted in Oracle's Critical Patch Update Advisory, the application of the most recent Critical Patch Update will bring these products to current security patch level and provide the organization with the best possible security posture for their patch level. Furthermore, organizations are encouraged to upgrade to most recent versions as this will greatly improve their security posture. At Oracle, our security fixing policies state that security fixes are produced for the main code line first, and as a result, our products benefit from the mistakes made in previous version(s). Our ongoing assurance effort ensures that we work diligently to fix the vulnerabilities we find, and aim at constantly improving the security posture our products provide by default. Patch sets include numerous in-depth fixes in addition to those delivered through the Critical Patch Update and, in certain instances, important security fixes require major architectural changes that can only be included in new product releases (and cannot be backported through the Critical Patch Update program). For More Information: • Mary Ann Davidson is giving a webcast interview on Oracle Software Security Assurance on February 24th. The registration link for attending this webcast is located at http://event.on24.com/r.htm?e=280304&s=1&k=6A7152F62313CA09F77EBCEEA9B6294F&partnerref=EricMblog • A blog entry discussing Oracle's practices for ensuring the quality of Critical patch Updates can be found at http://blogs.oracle.com/security/2009/07/ensuring_critical_patch_update_quality.html • The blog entry "To patch or not to patch" is located at http://blogs.oracle.com/security/2008/01/to_patch_or_not_to_patch.html • Oracle's Support Policies are located at http://www.oracle.com/us/support/policies/index.html • The Critical Patch Update & Security Alert page is located at http://www.oracle.com/technetwork/topics/security/alerts-086861.html

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• A deadlock was detected while trying to lock variables in SSIS

  Error: 0xC001405C at SQL Log Status: A deadlock was detected while trying to lock variables "User::RowCount" for read/write access. A lock cannot be acquired after 16 attempts. The locks timed out. Have you ever considered variable locking when building your SSIS packages? I expect many people haven’t just because most of the time you never see an error like the one above. I’ll try and explain a few key concepts about variable locking and hopefully you never will see that error. First of all, what is all this variable locking all about? Put simply SSIS variables have to be locked before they can be accessed, and then of course unlocked once you have finished with them. This is baked into SSIS, presumably to reduce the risk of race conditions, but with that comes some additional overhead in that you need to be careful to avoid lock conflicts in some scenarios. The most obvious place you will come across any hint of locking (no pun intended) is the Script Task or Script Component with their ReadOnlyVariables and ReadWriteVariables properties. These two properties allow you to enter lists of variables to be used within the task, or to put it another way, these lists of variables to be locked, so that they are available within the task. During the task pre-execute phase the variables and locked, you then use them during the execute phase when you code is run, and then unlocked for you during the post-execute phase. So by entering the variable names in one of the two list, the locking is taken care of for you, and you just read and write to the Dts.Variables collection that is exposed in the task for the purpose. As you can see in the image above, the variable PackageInt is specified, which means when I write the code inside that task I don’t have to worry about locking at all, as shown below. public void Main() { // Set the variable value to something new Dts.Variables["PackageInt"].Value = 199; // Raise an event so we can play in the event handler bool fireAgain = true; Dts.Events.FireInformation(0, "Script Task Code", "This is the script task raising an event.", null, 0, ref fireAgain); Dts.TaskResult = (int)ScriptResults.Success; } As you can see as well as accessing the variable, hassle free, I also raise an event. Now consider a scenario where I have an event hander as well as shown below. Now what if my event handler uses tries to use the same variable as well? Well obviously for the point of this post, it fails with the error quoted previously. The reason why is clearly illustrated if you consider the following sequence of events. Package execution starts Script Task in Control Flow starts Script Task in Control Flow locks the PackageInt variable as specified in the ReadWriteVariables property Script Task in Control Flow executes script, and the On Information event is raised The On Information event handler starts Script Task in On Information event handler starts Script Task in On Information event handler attempts to lock the PackageInt variable (for either read or write it doesn’t matter), but will fail because the variable is already locked. The problem is caused by the event handler task trying to use a variable that is already locked by the task in Control Flow. Events are always raised synchronously, therefore the task in Control Flow that is raising the event will not regain control until the event handler has completed, so we really do have un-resolvable locking conflict, better known as a deadlock. In this scenario we can easily resolve the problem by managing the variable locking explicitly in code, so no need to specify anything for the ReadOnlyVariables and ReadWriteVariables properties. public void Main() { // Set the variable value to something new, with explicit lock control Variables lockedVariables = null; Dts.VariableDispenser.LockOneForWrite("PackageInt", ref lockedVariables); lockedVariables["PackageInt"].Value = 199; lockedVariables.Unlock(); // Raise an event so we can play in the event handler bool fireAgain = true; Dts.Events.FireInformation(0, "Script Task Code", "This is the script task raising an event.", null, 0, ref fireAgain); Dts.TaskResult = (int)ScriptResults.Success; } Now the package will execute successfully because the variable lock has already been released by the time the event is raised, so no conflict occurs. For those of you with a SQL Engine background this should all sound strangely familiar, and boils down to getting in and out as fast as you can to reduce the risk of lock contention, be that SQL pages or SSIS variables. Unfortunately we cannot always manage the locking ourselves. The Execute SQL Task is very often used in conjunction with variables, either to pass in parameter values or get results out. Either way the task will manage the locking for you, and will fail when it cannot lock the variables it requires. The scenario outlined above is clear cut deadlock scenario, both parties are waiting on each other, so it is un-resolvable. The mechanism used within SSIS isn’t actually that clever, and whilst the message says it is a deadlock, it really just means it tried a few times, and then gave up. The last part of the error message is actually the most accurate in terms of the failure, A lock cannot be acquired after 16 attempts. The locks timed out.  Now this may come across as a recommendation to always manage locking manually in the Script Task or Script Component yourself, but I think that would be an overreaction. It is more of a reminder to be aware that in high concurrency scenarios, especially when sharing variables across multiple objects, locking is important design consideration. Update – Make sure you don’t try and use explicit locking as well as leaving the variable names in the ReadOnlyVariables and ReadWriteVariables lock lists otherwise you’ll get the deadlock error, you cannot lock a variable twice!

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• Caveat utilitor - Can I run two versions of Microsoft Project side-by-side?

  - by Martin Hinshelwood

  A number of out customers have asked if there are any problems in installing and running multiple versions of Microsoft Project on a single client. Although this is a case of Caveat utilitor (Let the user beware), as long as the user understands and accepts the issues that can occur then they can do this. Although Microsoft provide the ability to leave old versions of Office products (except Outlook) on your client when you are installing a new version of the product they certainly do not endorse doing so. Figure: For Project you can choose to keep the old stuff   That being the case I would have preferred that they put a “(NOT RECOMMENDED)” after the options to impart that knowledge to the rest of us, but they did not. The default and recommended behaviour is for the newer version installer to remove the older versions. Of course this does not apply in the revers. There are no forward compatibility packs for Office. There are a number of negative behaviours (or bugs) that can occur in this configuration: There is only one MS Project In Windows a file extension can only be associated with a single program.  In this case, MPP files can be associated with only one version of winproj.exe.  The executables are in different folders so if a user double-clicks a Project file on the desktop, file explorer, or Outlook email, Windows will launch the winproj.exe associated with MPP and then load the MPP file.  There are problems associated with this situation and in some cases workarounds. The user double-clicks on a Project 2010 file, Project 2007 launches but is unable to open the file because it is a newer version.  The workaround is for the user to launch Project 2010 from the Start menu then open the file.  If the file is attached to an email they will need to first drag the file to the desktop. All your linked MS Project files need to be of the same version There are a number of problems that occur when people use on Microsoft’s Object Linking and Embedding (OLE) technology.  The three common uses of OLE are: for inserted projects where a Master project contains sub-projects and each sub-project resides in its own MPP file shared resource pools where multiple MPP files share a common resource pool kept in a single MPP file cross-project links where a task or milestone in one MPP file has a  predecessor/successor relationship with a task or milestone in a different MPP file What I’ve seen happen before is that if you are running in a version of Project that is not associated with the MPP extension and then try and activate an OLE link then Project tries to launch the other version of Project.  Things start getting very confused since different MPP files are being controlled by different versions of Project running at the same time.  I haven’t tried this in awhile so I can’t give you exact symptoms but I suspect that if Project 2010 is involved the symptoms will be different then in a Project 2003/2007 scenario.  I’ve noticed that Project 2010 gives different error messages for the exact same problem when it occurs in Project 2003 or 2007.  -Anonymous The recommendation would be either not to use this feature if you have to have multiple versions of Project installed or to use only a single version of Project. You may get unexpected negative behaviours if you are using shared resource pools or resource pools even when you are not running multiple versions as I have found that they can get broken very easily. If you need these thing then it is probably best to use Project Server as it was created to solve many of these specific issues. Note: I would not even allow multiple people to access a network copy of a Project file because of the way Windows locks files in write mode. This can cause write-locks that get so bad a server restart is required I’ve seen user’s files get write-locked to the point where the only resolution is to reboot the server. Changing the default version to run for an extension So what if you want to change the default association from Project 2007 to Project 2010?   Figure: “Control Panel | Folder Options | Change the file associated with a file extension” Windows normally only lists the last version installed for a particular extension. You can select a specific version by selecting the program you want to change and clicking “Change program… | Browse…” and then selecting the .exe you want to use on the file system. Figure: You will need to select the exact version of “winproj.exe” that you want to run Conclusion Although it is possible to run multiple versions of Project on one system in the main it does not really make sense.

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• BizTalk: Sample: Context routing and Throttling with orchestration

  - by Leonid Ganeline

  The sample demonstrates using orchestration for throttling and using context routing. Usually throttling is implemented on the host level (in BizTalk 2010 we can also using the host instance level throttling). Here is demonstrated the throttling with orchestration convoy that slows down message flow from some customers. Sample implements sort of quality service agreement layer for different kind of customers. The sample demonstrates the context routing between orchestrations. It has several advantages over the content routing. For example, we don’t have to create the property schema and promote properties on the schemas; we don’t have to change the message content to change routing. Use case:  The BizTalk application has a main processing orchestration that process all input messages. The application usually works as an OLTP application. Input messages came in random order without peaks, typical scenario for the on-line users. But sometimes the big data batch payloads come. These batches overload processing orchestrations. All processes, activated by on-line users after the payload, come to the same queue and are processed only after the payload. Result is on-line users can see significant delay in processing. It can be minutes or hours, depending of the batch size. Requirements: On-line user’s processing should work without delays. Big batches cannot disturb on-line users. There should be higher priority for the on-line users and the lower priority for the batches. Design: Decision is to divide the message flow in two branches, one for on-line users and second for batches. Branch with batches provides messages to the processing line with low priority, and the on-line user’s branch – with high priority. All messages are provided by hi-speed receive port. BTS.ReceivePortName context property is used for routing. The Router orchestration separates messages sent from on-line users and from the batch messages. But the Router does not use the BizTalk provided value of this property, the Router set up this value by itself. Router uses the content of the messages to decide if it is from on-line users or from batches. The message context property the BTS.ReceivePortName is changed respectively, its value works as a recipient address, as the “To” address for the next recipient orchestrations. Those next orchestrations are the BatchBottleneck and the MainProcess orchestrations. Messages with context equal “ToBatch” are filtered up by the BatchBottleneck orchestration. It is a unified convoy orchestration and it throttles the message flow, delaying the message delivery to the MainProcess orchestration. The BatchBottleneck orchestration changes the message context to the “ToProcess” and sends messages one after another with small delay in between. Delay can be configured in the BizTalk config file as:                 <appSettings>                                 <add key="GLD_Tests_TwoWayRouting_BatchBottleneck_DelayMillisec" value="100"/>                 </appSettings>   Of course, messages with context equal “ToProcess” are filtered up by the MainProcess orchestration.   NOTES: Filters with string values: In Orchestrations (the first Receive shape in orchestration) use string values WITH quotes; in Send Ports use string values WITHOUT quotes. Filters on the Send Ports are dynamic; we can change them in run-time. Filters on the Orchestrations are static; we can change them only in design-time. To check the existence of the promoted property inside orchestration use the Expression shape with construction like this:       if (BTS.ReceivePortName exists myMessage) { …; } It is not possible in the Message Assignment shape because using the “if” statement inside Message Assignment is prohibited. Several predefined context properties can behave in specific way. Say MessageTracking.OriginatingMessage or XMLNORM.DocumentSpecName, they are required some internal rules should be applied to the format or usage of this properties. MessageTracking.* parameters require you have to use tracking and you can get unexpected run-time errors in some cases. My recommendation is - use very limited set of the predefined context properties. To “attach” the new promoted property to the message, we have to use correlation. The correlation type should include this property. [Here is a good explanation by Saravana ] The sample code is here [sorry, temporary trubles with CodePlex].

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• Speakers, Please Check Your Time

  - by AjarnMark

  Woodrow Wilson was once asked how long it would take him to prepare for a 10 minute speech. He replied "Two weeks". He was then asked how long it would take for a 1 hour speech. "One week", he replied. 2 hour speech? "I'm ready right now," he replied.  Whether that is a true story or an urban legend, I don’t really know, but either way, it is a poignant reminder for all speakers, and particularly apropos this week leading up to the PASS Community Summit. (Cross-posted to the PASS Professional Development Virtual Chapter blog #PASSProfDev.) What’s the point of that story?  Simply this…if you have plenty of time to do your presentation, you don’t need to prepare much because it is easy to throw in more and more material to stretch out to your allotted time.  But if you are on a tight time constraint, then it will take significant preparation to distill your talk down to only the essential points. I have attended seven of the last eight North American Summit events, and every one of them has been fantastic.  The speakers are great, the material is timely and relevant, and the networking opportunities are awesome.  And every year, there is one little thing that just bugs me…speakers going over their allotted time.  Why does it bother me so?  Well, if you look at a typical schedule for a Summit, you’ll see that there are six or more sessions going on at the same time, and only 15 minutes to move from one to another.  If you’re trying to maximize your training dollar by attending something during every session time slot, and you don’t want to be the last guy trying to squeeze into the middle of the row, then those 15 minutes can be critical.  All the more so if you need to stop and use the bathroom or if you have to hike to the opposite end of the convention center.  It is really a bad position to find yourself having to choose between learning the last key points of Speaker A who is going over time, and getting over to Speaker B on time so you don’t miss her key opening remarks. And frankly, I think it is just rude.  Yes, the speakers are the function, after all they are bringing the content that the rest of us are paying to learn.  But it is also an honor to be given the opportunity to speak at a conference like this, and no one speaker is so important that the conference would be a disaster without him.  Speakers know when they submit their abstract, long before the conference, how much time they will have.  It has been the same pattern at the Summit for at least the last eight years.  Program Sessions are 75 minutes long.  Some speakers who have a good track record, and meet other qualifying criteria, are extended an invitation to present a Spotlight Session which is 90 minutes (a 20% increase).  So there really is no excuse.  It’s not like you were promised a 2-hour segment and then discovered when you got here that it was only 75 minutes.  In fact, it’s not like PASS advertised 90-minute sessions for everyone and then a select few were cut back to only 75.  As a speaker, you know well before you get here which type of session you are doing and how long it is, so as a professional, you should plan accordingly. Now you might think that this only happens to rookies, but I’ll tell you that some of the worst offenders are big-name veterans who draw huge attendance numbers for their sessions.  Some attendees blow this off as, “Hey, it’s so-and-so, and I’d stay here for hours and listen to him/her talk.”  To which I would reply, “Then they should have submitted for a pre- or post-conference day-long seminar instead, but don’t try to squeeze your day-long talk into a 90-minute session.”  Now I don’t really believe that these speakers are being malicious or just selfishly trying to extend their time in the spotlight.  I think that most of them are merely being undisciplined and did not trim their presentation sufficiently, or allowed themselves to get off-track (often in a generous attempt to help someone in the audience with a question or problem that really should have been noted for further discussion after the session). So here is my recommendation…my plea, even.  TRIM THE FAT!  Now.  Before it’s too late.  Before you even get on the airplane, take a long, hard look at your presentation and eliminate some of the points that you originally thought you had to make, but in reality are not truly crucial to your main topic.  Delete a few slides.  Test your demos and have them already scripted rather than typing them during your talk.  It is better to cut out too much and end up with plenty of time at the end for Questions & Answers.  And you can always keep some notes on the stuff that you cut out so that you could fill it back in at the end as bonus material if you really do end up with a whole bunch of time on your hands.  But I don’t think you will.  And if you do, that will look even better to the audience as it will look like you’re giving them something extra that not every audience gets.  And they will thank you for that.

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• Developing Schema Compare for Oracle (Part 6): 9i Query Performance

  - by Simon Cooper

  All throughout the EAP and beta versions of Schema Compare for Oracle, our main request was support for Oracle 9i. After releasing version 1.0 with support for 10g and 11g, our next step was then to get version 1.1 of SCfO out with support for 9i. However, there were some significant problems that we had to overcome first. This post will concentrate on query execution time. When we first tested SCfO on a 9i server, after accounting for various changes to the data dictionary, we found that database registration was taking a long time. And I mean a looooooong time. The same database that on 10g or 11g would take a couple of minutes to register would be taking upwards of 30 mins on 9i. Obviously, this is not ideal, so a poke around the query execution plans was required. As an example, let's take the table population query - the one that reads ALL_TABLES and joins it with a few other dictionary views to get us back our list of tables. On 10g, this query takes 5.6 seconds. On 9i, it takes 89.47 seconds. The difference in execution plan is even more dramatic - here's the (edited) execution plan on 10g: -------------------------------------------------------------------------------| Id | Operation | Name | Bytes | Cost |-------------------------------------------------------------------------------| 0 | SELECT STATEMENT | | 108K| 939 || 1 | SORT ORDER BY | | 108K| 939 || 2 | NESTED LOOPS OUTER | | 108K| 938 ||* 3 | HASH JOIN RIGHT OUTER | | 103K| 762 || 4 | VIEW | ALL_EXTERNAL_LOCATIONS | 2058 | 3 ||* 20 | HASH JOIN RIGHT OUTER | | 73472 | 759 || 21 | VIEW | ALL_EXTERNAL_TABLES | 2097 | 3 ||* 34 | HASH JOIN RIGHT OUTER | | 39920 | 755 || 35 | VIEW | ALL_MVIEWS | 51 | 7 || 58 | NESTED LOOPS OUTER | | 39104 | 748 || 59 | VIEW | ALL_TABLES | 6704 | 668 || 89 | VIEW PUSHED PREDICATE | ALL_TAB_COMMENTS | 2025 | 5 || 106 | VIEW | ALL_PART_TABLES | 277 | 11 |------------------------------------------------------------------------------- And the same query on 9i: -------------------------------------------------------------------------------| Id | Operation | Name | Bytes | Cost |-------------------------------------------------------------------------------| 0 | SELECT STATEMENT | | 16P| 55G|| 1 | SORT ORDER BY | | 16P| 55G|| 2 | NESTED LOOPS OUTER | | 16P| 862M|| 3 | NESTED LOOPS OUTER | | 5251G| 992K|| 4 | NESTED LOOPS OUTER | | 4243M| 2578 || 5 | NESTED LOOPS OUTER | | 2669K| 1440 ||* 6 | HASH JOIN OUTER | | 398K| 302 || 7 | VIEW | ALL_TABLES | 342K| 276 || 29 | VIEW | ALL_MVIEWS | 51 | 20 ||* 50 | VIEW PUSHED PREDICATE | ALL_TAB_COMMENTS | 2043 | ||* 66 | VIEW PUSHED PREDICATE | ALL_EXTERNAL_TABLES | 1777K| ||* 80 | VIEW PUSHED PREDICATE | ALL_EXTERNAL_LOCATIONS | 1744K| ||* 96 | VIEW | ALL_PART_TABLES | 852K| |------------------------------------------------------------------------------- Have a look at the cost column. 10g's overall query cost is 939, and 9i is 55,000,000,000 (or more precisely, 55,496,472,769). It's also having to process far more data. What on earth could be causing this huge difference in query cost? After trawling through the '10g New Features' documentation, we found item 1.9.2.21. Before 10g, Oracle advised that you do not collect statistics on data dictionary objects. From 10g, it advised that you do collect statistics on the data dictionary; for our queries, Oracle therefore knows what sort of data is in the dictionary tables, and so can generate an efficient execution plan. On 9i, no statistics are present on the system tables, so Oracle has to use the Rule Based Optimizer, which turns most LEFT JOINs into nested loops. If we force 9i to use hash joins, like 10g, we get a much better plan: -------------------------------------------------------------------------------| Id | Operation | Name | Bytes | Cost |-------------------------------------------------------------------------------| 0 | SELECT STATEMENT | | 7587K| 3704 || 1 | SORT ORDER BY | | 7587K| 3704 ||* 2 | HASH JOIN OUTER | | 7587K| 822 ||* 3 | HASH JOIN OUTER | | 5262K| 616 ||* 4 | HASH JOIN OUTER | | 2980K| 465 ||* 5 | HASH JOIN OUTER | | 710K| 432 ||* 6 | HASH JOIN OUTER | | 398K| 302 || 7 | VIEW | ALL_TABLES | 342K| 276 || 29 | VIEW | ALL_MVIEWS | 51 | 20 || 50 | VIEW | ALL_PART_TABLES | 852K| 104 || 78 | VIEW | ALL_TAB_COMMENTS | 2043 | 14 || 93 | VIEW | ALL_EXTERNAL_LOCATIONS | 1744K| 31 || 106 | VIEW | ALL_EXTERNAL_TABLES | 1777K| 28 |------------------------------------------------------------------------------- That's much more like it. This drops the execution time down to 24 seconds. Not as good as 10g, but still an improvement. There are still several problems with this, however. 10g introduced a new join method - a right outer hash join (used in the first execution plan). The 9i query optimizer doesn't have this option available, so forcing a hash join means it has to hash the ALL_TABLES table, and furthermore re-hash it for every hash join in the execution plan; this could be thousands and thousands of rows. And although forcing hash joins somewhat alleviates this problem on our test systems, there's no guarantee that this will improve the execution time on customers' systems; it may even increase the time it takes (say, if all their tables are partitioned, or they've got a lot of materialized views). Ideally, we would want a solution that provides a speedup whatever the input. To try and get some ideas, we asked some oracle performance specialists to see if they had any ideas or tips. Their recommendation was to add a hidden hook into the product that allowed users to specify their own query hints, or even rewrite the queries entirely. However, we would prefer not to take that approach; as well as a lot of new infrastructure & a rewrite of the population code, it would have meant that any users of 9i would have to spend some time optimizing it to get it working on their system before they could use the product. Another approach was needed. All our population queries have a very specific pattern - a base table provides most of the information we need (ALL_TABLES for tables, or ALL_TAB_COLS for columns) and we do a left join to extra subsidiary tables that fill in gaps (for instance, ALL_PART_TABLES for partition information). All the left joins use the same set of columns to join on (typically the object owner & name), so we could re-use the hash information for each join, rather than re-hashing the same columns for every join. To allow us to do this, along with various other performance improvements that could be done for the specific query pattern we were using, we read all the tables individually and do a hash join on the client. Fortunately, this 'pure' algorithmic problem is the kind that can be very well optimized for expected real-world situations; as well as storing row data we're not using in the hash key on disk, we use very specific memory-efficient data structures to store all the information we need. This allows us to achieve a database population time that is as fast as on 10g, and even (in some situations) slightly faster, and a memory overhead of roughly 150 bytes per row of data in the result set (for schemas with 10,000 tables in that means an extra 1.4MB memory being used during population). Next: fun with the 9i dictionary views.

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• Python soap using soaplib (server) and suds (client)

  - by Celso Axelrud

  This question is related to: http://stackoverflow.com/questions/1751027/python-soap-server-client In the case of soap with python, there are recommendation to use soaplib (http://wiki.github.com/jkp/soaplib) as soap server and suds (https://fedorahosted.org/suds/) as soap client. My target is to create soap services in python that can be consumed by several clients (java, etc). I tried the HelloWorld example from soaplib (http://trac.optio.webfactional.com/wiki/HelloWorld). It works well when the client is also using soaplib. Then, I tried to use suds as client consuming the HelloWorld services and it fail. -Why this is happening? Does soaplib server has problems to consumed by different clients? Here the code for the server: from soaplib.wsgi_soap import SimpleWSGISoapApp from soaplib.service import soapmethod from soaplib.serializers.primitive import String, Integer, Arraycode class HelloWorldService(SimpleWSGISoapApp): @soapmethod(String,Integer,_returns=Array(String)) def say_hello(self,name,times): results = [] for i in range(0,times): results.append('Hello, %s'%name) return results if __name__=='__main__': from cherrypy.wsgiserver import CherryPyWSGIServer #from cherrypy._cpwsgiserver import CherryPyWSGIServer # this example uses CherryPy2.2, use cherrypy.wsgiserver.CherryPyWSGIServer for CherryPy 3.0 server = CherryPyWSGIServer(('localhost',7789),HelloWorldService()) server.start() This is the soaplib client: from soaplib.client import make_service_client from SoapServerTest_1 import HelloWorldService client = make_service_client('http://localhost:7789/',HelloWorldService()) print client.say_hello("Dave",5) Results: >>> ['Hello, Dave', 'Hello, Dave', 'Hello, Dave', 'Hello, Dave', 'Hello, Dave'] This is the suds client: from suds.client import Client url = 'http://localhost:7789/HelloWordService?wsdl' client1 = Client(url) client1.service.say_hello("Dave",5) Results: >>> Unhandled exception while debugging... Traceback (most recent call last): File "C:\Python25\Lib\site-packages\RTEP\Sequencing\SoapClientTest_1.py", line 10, in <module> client1.service.say_hello("Dave",5) File "c:\python25\lib\site-packages\suds\client.py", line 537, in __call__ return client.invoke(args, kwargs) File "c:\python25\lib\site-packages\suds\client.py", line 597, in invoke result = self.send(msg) File "c:\python25\lib\site-packages\suds\client.py", line 626, in send result = self.succeeded(binding, reply.message) File "c:\python25\lib\site-packages\suds\client.py", line 658, in succeeded r, p = binding.get_reply(self.method, reply) File "c:\python25\lib\site-packages\suds\bindings\binding.py", line 158, in get_reply result = unmarshaller.process(nodes[0], resolved) File "c:\python25\lib\site-packages\suds\umx\typed.py", line 66, in process return Core.process(self, content) File "c:\python25\lib\site-packages\suds\umx\core.py", line 48, in process return self.append(content) File "c:\python25\lib\site-packages\suds\umx\core.py", line 63, in append self.append_children(content) File "c:\python25\lib\site-packages\suds\umx\core.py", line 140, in append_children cval = self.append(cont) File "c:\python25\lib\site-packages\suds\umx\core.py", line 61, in append self.start(content) File "c:\python25\lib\site-packages\suds\umx\typed.py", line 77, in start found = self.resolver.find(content.node) File "c:\python25\lib\site-packages\suds\resolver.py", line 341, in find frame = Frame(result, resolved=known, ancestry=ancestry) File "c:\python25\lib\site-packages\suds\resolver.py", line 473, in __init__ resolved = type.resolve() File "c:\python25\lib\site-packages\suds\xsd\sxbasic.py", line 63, in resolve raise TypeNotFound(qref) TypeNotFound: Type not found: '(string, HelloWorldService.HelloWorldService, )'

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• XML: Process large data

  - by Atmocreations

  Hello What XML-parser do you recommend for the following purpose: The XML-file (formatted, containing whitespaces) is around 800 MB. It mostly contains three types of tag (let's call them n, w and r). They have an attribute called id which i'd have to search for, as fast as possible. Removing attributes I don't need could save around 30%, maybe a bit more. First part for optimizing the second part: Is there any good tool (command line linux and windows if possible) to easily remove unused attributes in certain tags? I know that XSLT could be used. Or are there any easy alternatives? Also, I could split it into three files, one for each tag to gain speed for later parsing... Speed is not too important for this preparation of the data, of course it would be nice when it took rather minutes than hours. Second part: Once I have the data prepared, be it shortened or not, I should be able to search for the ID-attribute I was mentioning, this being time-critical. Estimations using wc -l tell me that there are around 3M N-tags and around 418K W-tags. The latter ones can contain up to approximately 20 subtags each. W-Tags also contain some, but they would be stripped away. "All I have to do" is navigating between tags containing certain id-attributes. Some tags have references to other id's, therefore giving me a tree, maybe even a graph. The original data is big (as mentioned), but the resultset shouldn't be too big as I only have to pick out certain elements. Now the question: What XML parsing library should I use for this kind of processing? I would use Java 6 in a first instance, with having in mind to be porting it to BlackBerry. Might it be useful to just create a flat file indexing the id's and pointing to an offset in the file? Is it even necessary to do the optimizations mentioned in the upper part? Or are there parser known to be quite as fast with the original data? Little note: To test, I took the id being on the very last line on the file and searching for the id using grep. This took around a minute on a Core 2 Duo. What happens if the file grows even bigger, let's say 5 GB? I appreciate any notice or recommendation. Thank you all very much in advance and regards

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• Web Safe Area (optimal resolution) for web app design

  - by M.A.X

  I'm in the process of designing a new web app and I'm wondering for what 'web safe area' should I optimize the app layout and design. I did some investigation and thinking on my own but wanted to share this to see what the general opinion is. Here is what I found: Optimal Display Resolution: w3schools web stats seems to be the most referenced source (however they state that these are results from their site and is biased towards tech savvy users) http://www.w3counter.com/globalstats.php (aggregate data from something like 15,000 different sites that use their tracking services) StatCounter Global Stats Display Resolution (Stats are based on aggregate data collected by StatCounter on a sample exceeding 15 billion pageviews per month collected from across the StatCounter network of more than 3 million websites) NetMarketShare Screen Resolutions (marketshare.hitslink.com) (a web analytics consulting firm, they get data from browsers of site visitors to their on-demand network of live stats customers. The data is compiled from approximately 160 million visitors per month) Display Resolution Summary: There is a bit of variation between the above sources but in general as of Jan 2011 looks like 1024x768 is about 20%, while ~85% have a higher resolution of at least 1280x768 (1280x800 is the most common of these with 15-20% of total web, depending on the source; 1280x1024 and 1366x768 follow behind with 9-14% of the share). My guess would be that the higher resolution values will be even more common if we filter on North America, and even higher if we filter on N.American corporate users (unfortunately I couldn't find any free geographically filtered statistics). Another point to note is that the 1024x768 desktop user population is likely lower than the aforementioned 20%, seeing as the iPad (1024x768 native display) is likely propping up those number. My recommendation would be to optimize around the 1280x768 constraint (*note: 1280x768 is actually a relatively rare resolution, but I think it's a valid constraint range considering that 1366x768 is relatively common and 1280 is the most common horizontal resolution). Browser + OS Constraints: To further add to the constraints we have to subtract the space taken up by the browser (assuming IE, which is the most space consuming) and the OS (assuming WinXP-Win7): Win7 has the biggest taskbar footprint at a height of 40px (XP's and Vista's is 30px) The default IE8 view uses up 25px at the bottom of the screen with the status bar and a further 120px at the top of the screen with the windows title bar and the browser UI (assuming the default 'favorites' toolbar is present, it would instead be 91px without the favorites toolbar). Assuming no scrollbar, we also loose a total of 4px horizontally for the window outline. This means that we are left with 583px of vertical space and 1276px of horizontal. In other words, a Web Safe Area of 1276 x 583 Is this a correct line of thinking? I tried to Google some design best practices but most still talk about designing around 1024x768 which seems to be quickly disappearing. Any help on this would be greatly appreciated! Thanks.

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• DOM memory issue with IE8 (inserting lots of JSON data)

  - by okie.floyd

  i am developing a small web-utility that displays some data from some database tables. i have the utility running fine on FF, Safari, Chrome..., but the memory management on IE8 is horrendous. the largest JSON request I do will return information to create around 5,000 or so rows in a table within the browser (3 columns in the table). i'm using jquery to get the data (via getJSON). to remove the old/existing table, i'm just doing a $('#my_table_tbody').empty(). to add the new info to the table, within the getJSON callback, i am just appending each table row that i am creating to a variable, and then once i have them all, i am using $('#my_table_tbody').append(myVar) to add it to the existing tbody. i don't add the table rows as they are created because that seems to be a lot slower than just adding them all at once. does anyone have any recommendation on what someone should do who is trying to add thousands of rows of data to the DOM? i would like to stay away from pagination, but i'm wondering if i don't have a choice. Update 1 So here is the code I was trying after the innerHTML suggestion: /* Assuming a div called 'main_area' holds the table */ document.getElementById('main_area').innerHTML = ''; $.getJSON("my_server", {my: JSON, args: are, in: here}, function(j) { var mylength = j.length; var k =0; var tmpText = ''; tmpText += /* Add the table, thead stuff, and tbody tags here */; for (k = mylength - 1; k = 0; k--) { /* stack overflow wont let me type greater than & less than signs here, so just assume that they are there. */ tmpText += 'tr class="' + j[k].row_class . '" td class="col1_class" ' + j[k].col1 + ' /td td class="col2_class" ' + j[k].col2 + ' /td td class="col3_class" ' + j[k].col3 + ' /td /tr'; } document.getElementById('main_area').innerHTML = tmpText; } That is the gist of it. I've also tried using just a $.get request, and having the server send the formatted HTML, and just setting that in the innerHTML (i.e. document.getElementById('main_area').innerHTML = j;). thanks for all of the replies. i'm floored with the fact that you all are willing to help.

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• Is it OK to put a standard, pure C header #include directive inside a namespace?

  - by mic_e

  I've got a project with a class log in the global namespace (::log). So, naturally, after #include <cmath>, the compiler gives an error message each time I try to instantiate an object of my log class, because <cmath> pollutes the global namespace with lots of three-letter methods, one of them being the logarithm function log(). So there are three possible solutions, each having their unique ugly side-effects. Move the log class to it's own namespace and always access it with it's fully qualified name. I really want to avoid this because the logger should be as convenient as possible to use. Write a mathwrapper.cpp file which is the only file in the project that includes <cmath>, and makes all the required <cmath> functions available through wrappers in a namespace math. I don't want to use this approach because I have to write a wrapper for every single required math function, and it would add additional call penalty (cancelled out partially by the -flto compiler flag) The solution I'm currently considering: Replace #include <cmath> by namespace math { #include "math.h" } and then calculating the logarithm function via math::log(). I have tried it out and it does, indeed, compile, link and run as expected. It does, however, have multiple downsides: It's (obviously) impossible to use <cmath>, because the <cmath> code accesses the functions by their fully qualified names, and it's deprecated to use in C++. I've got a really, really bad feeling about it, like I'm gonna get attacked and eaten alive by raptors. So my question is: Is there any recommendation/convention/etc that forbid putting include directives in namespaces? Could anything go wrong with diferent C standard library implementations (I use glibc), different compilers (I use g++ 4.7, -std=c++11), linking? Have you ever tried doing this? Are there any alternate ways to banish the math functions from the global namespace? I've found several similar questions on stackoverflow, but most were about including other C++ headers, which obviously is a bad idea, and those that weren't made contradictory statements about linking behaviour for C libraries. Also, would it be beneficial to additionally put the #include <math.h> inside extern "C" {}?

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• DHCP and DNS services configuration for VOIP system, windows domain, etc

  - by Stemen

  My company has numerous physical offices (for purposes of this discussion, 15 buildings). Some of them are well-connected to our primary data center via fiber. Others will be connected to the data center by P2P T1. We are in the beginning stages of implementing an Avaya VOIP telephone system, and we will be replacing a significant portion of our network infrastructure in the process. In tandem with the phone system implementation, we are going to be re-addressing some of our networks, and consolidating most of our Windows domains into one (not all domains, just most). We currently have quite a few Windows domains, and they of course each have their own DNS zones. A few of those networks currently use DHCP, but the majority use static IP assignments for every device. I'm tired of managing static assignments -- I want to use DHCP configuration on everything except servers. Printers and etc will have DHCP reservations. The new IP phones will need to get IP addresses from DHCP, though they need to be in a separate VLAN from the computers/printers/etc. The computers and printers need to be registered in DNS. That's currently handled by the Windows DHCP servers on each of the respective domains. We need to place a priority on DHCP and DNS being available on a per-site basis (in case something were to interrupt the WAN connection) for computers and (primarily) phones. Smaller locations (which will have IP phones but not be a member of any Windows domain) will not have any Windows DNS/DHCP server(s) available. We also are looking for the easiest way to replace a part if it were to fail. That is to say, if a server/appliance/router hosting DHCP were to crash hard, and we couldn't extremely quickly recover the DHCP reservations and leases (and subsequently restore them onto a cold spare), we anticipate that bad things could happen. What is the best idea for how to re-implement DNS and DHCP keeping all of the above in mind? Some thoughts that have been raised (by myself or my coworkers): Use Windows DNS and DHCP servers, where they exist, and use IP helpers to route DHCP requests to some other Windows server if necessary. May not be acceptable if the WAN goes down and clients don't get a DHCP response. Use Windows DNS (everywhere, over WAN in some cases) and a mix of Windows DHCP and DHCP provided by Cisco routers. Every site would be covered for DHCP, but from what I've read, Cisco routers can't handle dynamic registration of DHCP clients to Windows DNS servers, which might create a problem where Cisco routers are used for DHCP. Use Windows DNS (everywhere, over WAN in some cases) and a mix of Windows DHCP and DHCP provided by some service running on an extremely low-price linux server. Is there any such software that would allow DHCP leases granted by these linux boxes to be dynamically registered on the Windows DNS servers? Come up with a Linux solution for both DNS and DHCP, and deploy low-price linux servers to every site. Requirements would be that the DNS zone be multi-master (like Windows DNS integrated with Active Directory), that DHCP be able to make dynamic DNS registrations in that zone, for every lease (where a hostname is provided and is thus possible), and that multiple servers be either authoritative for the same DHCP scope or at least receiving a real-time copy / replication / sync of the leases table so that if one server dies, we still know which MAC has what address. Purchase dedicated DNS/DHCP appliances, deploying to all sites. From what I read/see, this solves all of our technical problems. Then come the financial problems... I don't have a ton of money to spend on this. Or, some other solution that we've thus far overlooked and will consider upon recommendation. Can Cisco routers or Windows servers sync DHCP lease tables so that multiple servers can be authoritative (or active/passive for all I care) for the same scope, in case one of the partners were to fail? I've read online (repeatedly) that ISC's DHCP is able to maintain the same lease table across multiple servers, in order to solve this problem. Does anyone have any experience or advice to regarding that?

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• Why is the DNS on my Windows Server 2012 not authoritative according to dig?

  - by tetranz

  This is me trying to understand something rather than a real problem. I have a new Windows Server 2012 Essentials. That server provides, DNS, DHCP etc. Lets say my Windows domain is my-windows-domain and the server's host name is my-server. The domain's DNS zone is my-windows-domain.local. The server's IP address is 192.168.1.5. This is what I get if I go to a Linux machine on our LAN and do dig my-server.my-windows-domain @192.168.1.5 ; <<>> DiG 9.9.5-3-Ubuntu <<>> my-server.my-windows-domain.local @192.168.1.5 ;; global options: +cmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 6003 ;; flags: qr aa rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1 ;; OPT PSEUDOSECTION: ; EDNS: version: 0, flags:; udp: 4000 ;; QUESTION SECTION: ;my-server.my-windows-domain.local. IN A ;; ANSWER SECTION: my-server.my-windows-domain.local. 3600 IN A 192.168.1.5 ;; Query time: 0 msec ;; SERVER: 192.168.1.5#53(192.168.1.5) ;; WHEN: Wed Jun 11 10:44:28 EDT 2014 ;; MSG SIZE rcvd: 73 I think that all looks okay except why is it AUTHORITY: 0 ? Shouldn't this be the authority for the my-windows-server.local domain? dig soa my-windows-domain.local comes back with: ; <<>> DiG 9.9.5-3-Ubuntu <<>> soa my-windows-domain.local ;; global options: +cmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 29822 ;; flags: qr aa rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 2 ;; OPT PSEUDOSECTION: ; EDNS: version: 0, flags:; udp: 4000 ;; QUESTION SECTION: ;my-windows-domain.local. IN SOA ;; ANSWER SECTION: my-windows-domain.local. 3600 IN SOA my-server.my-windows-domain.local. hostmaster.my-windows-domain.local. 101 900 600 86400 3600 ;; ADDITIONAL SECTION: my-server.my-windows-domain.local. 3600 IN A 192.168.1.5 ;; Query time: 1 msec ;; SERVER: 192.168.1.5#53(192.168.1.5) ;; WHEN: Wed Jun 11 10:51:17 EDT 2014 ;; MSG SIZE rcvd: 120 I know about the recommendation to not use .local but there was no other option when I installed the server, just following the wizards.

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• Symantec Protection Suite and System Recovery 2011 Desktop Edition

  - by rihatum

  I am re-posting this as my previous question was being treated as if I am "Shopping or seeking Product Recommendations" even though I was NOT - BTW they have deleted my comments too which were not offensive in nature. anyway - I have re-phrased some parts of my question and I hope SF Admins "Do Not Modify / Edit" this one - will be most grateful for that. I have a lot of respect for the People who visit this SITE and help others ! Just To clarify : Just to go by SF rules - I am not seeking someone to Design this solution, I am simply seeking real world examples, experiences, technical expert opinions / suggestions, any tips or tricks they may have or any problems they may have faced while doing something similar above with these products. I am also not asking for Capacity Planning for Storage, We have done some research and I am seeking Expert Assurance / Suggestions. We (our company) are planning to deploy Symantec Endpoint Protection and Symantec Desktop Recovery 2011 Desktop Edition to our 3000 - 4000 workstations (Windows7 32 and 64) with a few 100s with Windows XP 32/64 Bit. I have read the implementation guide for SEP and have read tech-notes for Desktop Recovery 2011. Our team have planned to deploy this as follows : 1 x dedicated SQL 2008R2 for Symantec Endpoint Protection (Instead of using the Embedded Database) 1 x Dedicated SQL 2008R2 for Symantec Desktop Recovery 2011 (Instead of using the Embedded Database) 1 x Dedicated W2K8 R2 Box for the SEPM (Symantec Endpoint Protection Manager - Mgmt. APP) 1 x Dedicated W2K8 R2 Box for the Symantec Desktop Recovery 2011 Management Application Agent Deployment : As per Symantec Documentation for both of the above, an agent can be pushed via the Mgmt. Application (provided no firewalls are blocking ports required etc. - we have Windows firewall disabled already). Server Hardware : Per SQL Server : 16GB RAM + SAS DISKS + Dual XEON, RAID-10 for the SQL DB or I can always mount a LUN from our existing Hitachi or EMC SAN. SEPM Server : 16GB RAM + SAS DISKS + DUAL XEON System Recovery MGMT SERVER : 16GB RAM + SAS DISKS + DUAL XEON Above is the initial plan we have for 3000 - 4000 client workstation (Windows) Now my Questions :-) a) If we had these users distributed amongst two sites with AD DC / GC in each site, How would I restrict SEPM and Desktop Mgmt. solution to only check for users in their respective site ? b) At present all users are under one building but we are going to move some dept. to a new location (with dedicated connectivity), How would we control which SEPM / MGMT Server is responsible for which site ? c) We have netbackup in our environment backing up other servers, I am planning to protect these 4 (2 x SQL, 1 x SEPM, 1 x System Recovery Mgmt. Server) via netbackup or I can use System recovery 2011 server edition on all 4 of these boxes as well. (License is not an issue as we have the complete symantec portfolio included in our license). d) Now - Saving Desktop backups - What strategies have you implemented ? Any best practice recommendation for a large user base ? I was thinking to either mount a LUN from our Hitachi SAN on the Symantec Recovery Server itself or backup to the users hard drive locally and then copy it over to a network location ? Suggestions welcome :-) If you have anything to add / correct - that will be really helpful before diving into the actual implementation phase. Will be most grateful with your suggestions, recommendations and corrections with above - Many Thanks !

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• Pairing Bluetooth device with PIN fails

  - by Pikaro

  I'm trying to pair my old BlackBerry 8310 to my Linux desktop (up-to-date Debian Sid, 3.15-10.dmz.1-liquorix-amd64) by using blueman and its associated tools. Scanning for the device works equally well for both sides; however, I am unable to pair the two once it comes to entering the PIN. If I scan from my PC, I have two options in blueman-manager regarding my phone: Directly selecting "pair", or selecting "setup". If I select "pair", nothing happens on my desktop, but the phone asks me to enter a PIN; if I do so, it reports that pairing has failed. During that, nothing is logged to the console. Selecting "setup" opens a configuration dialog that allows for entering or generating a PIN. Regardless, I get to a screen that tells me to enter the PIN on the phone, and at the same time, the phone pops up the equivalent dialog. This would be what one would expect to work; but whatever I enter (naturally, the same on both), both devices report that pairing has failed, and blueman-manager logs init_services (/usr/lib/python2.7/dist-packages/blueman/main/Device.py:73) Loading services org.bluez.Error.AuthenticationFailed: Authentication Failed If I instead try to pair from the phone, I cannot see any kind of reaction from my desktop - all I get is the equivalent "pairing failed" message from the BlackBerry after I entered a PIN in the dialog that pops up there. hcitool scan and hciconfig -a work without complaints, but I cannot find a way to try the pairing as a whole on the console since bluez-simple-agent seems to have been discontinued and this recommendation is everywhere on Google. hcitool cc as root opens the PIN dialog on the phone, then fails with "Input/Output error" once I enter it. The user is not permitted to execute this command. I also tried creating /usr/lib/bluetooth/<MAC>/pincodes to manually define a persistent PIN, which seems to have had no effect. The same goes for running the different commands as root, though I'm really confused about the internal structure of the Bluetooth subsystem now: They usually and inconsistently failed with Python or DBUS errors or just showed the same results. The only other Bluetooth device I have around are a pair of Creative speakers. Trying "setup" asks me to enter a key on them, which is impossible. If I try "pair", I'm asked for a PIN as I should, but no pairing takes place, and no errors appear on the console. (It just repeats their name a few times.) Interestingly, I tried that before writing my question, and nothing happened in terms of PIN questions, just like with the BlackBerry, which still shows no change. I don't think I actively changed anything since then. The BlackBerry can pair with and connect to the speakers, and everything goes as one would expect, so the problem is definitely with my desktop. So thus my questions: What is that PIN window generated by, and why does it seem to appear randomly? How can I find out what, exactly, fails after trying to add the speakers, as this may give me a clue? Is there any kind of complete log that concerns itself with Bluetooth? What data can I provide to make this more solvable?

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• A failed disk (Pay for professional service or SpinRite?)(new edit)

  - by huggie

  EDIT: After much negotiating and begging and seeing through promotion smoke screen, thanks to the nice representative who took my case, I now know that the engineer has already fixed my NTFS partition (I guess it might be a bad block in the partition table?). She told me that the problem was considered minor, and I should be able to boot normally and just copy stuff out. Whew..I'm glad I didn't agree to the NTD $16,000 deal. New question (should this be in a new thread?): is it safer to use the linux "dd" command or is it better to boot normally into Windows XP and just copy stuff out? EDIT2: Thanks to all the help. I give the best answer to Console as it's most directed related to my question. But many suggestion are helpful and informational. ---- ORIGINAL POST BELOW --- Hi, in my previous post (You don't need to read but it's at http://superuser.com/questions/48838/windows-xp-a-disk-read-error-occurred), I said that my hard disk was not booting and is showing "a disk read error occurred". I took it to a recovery professional. A representative responded today told me that the NTFS partitions have a "NTFS partition system crash". I have no idea what that means. The engineer handling my drive will not be available for contact till tomorrow. Now the company charges me NTD (New Taiwan Dollar) $16,000 to recover lost data, that's kind of a lot considering that my graduate student monthly stipend is currently NTD $32,000 (max. allowed by regulation, may be lower, may change depend on funding). Now I'm weighting in between the options. Option A: let the professional recovers it with the half of my monthly stipend. If file/directories I designated are not recovered I don't pay a penny. (other than the initial examination fee of NTD $1000 which I've already paid.) Option B: let me try SpinRite, if failed, back to Option A. I spoke to the representative at the company they recommended me not to handle it on my own (yeah of course that's what they all want to say, right?), and at the price tag the disk error is probably relatively minor and data recoverable. But the representative really did not have detailed information of the disk failure so I didn't take her recommendation readily. Though one thing I heed was that she said that what they would do is to duplicate the disk before attempting discovery, so there would be no data loss (Is this true? can't duplicating invoke further data loss?). That sounds very good to me. Or maybe a third option: Option C: Negotiate with them to pay them to duplicate the disk hopefully for a much smaller price tag. Let me try SpinRite, if failed, back to Option A. This is a difficult decision. Ultimately I want my data back, but if a cheaper way is available to achieve the same thing... Can operating with SpinRite also corrupt data in someway? I've no idea what happened to my drive. I'll attempt to contact the engineer and hope to get it clarified and make an edit here.

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• Agile Awakenings and the Rules of Agile

  - by Robert May

  For those that care, you can read my history of management and technology to understand why I think I’m qualified to talk about this at all.  It’s boring, so feel free to skip it. Awakenings I first started to play around with the idea of “agile” in 2004 or 2005.  I found a book on the Rational Unified Process that I thought was good, and attempted to implement parts of it.  I thought I was agile, but really, it wasn’t.   I still didn’t understand the concept of a team.  I still wanted to tell the team what to do and how to get it done.  I still thought I was smarter than the team. After that job, I started work on another project and began helping that team.  The first few months were really rough.  We were implementing Scrum, which was relatively new to everyone on the team, and, quite frankly, I was doing a poor job of it.  I was trying to micro-manage every aspect of the teams work, and we were all miserable. The moment of change came when the senior architect bailed on the project.  His comment to me was: “This isn’t Agile.  Where are the stand-ups?  Where are the stories?”  He was dead on, and I finally woke up.  I finally realized that I was the problem!  I wasn’t trusting the team.  I wasn’t helping the team.  I was being a manager. Like many (most?), I was claiming to be Agile and use Scrum, but I wasn’t in fact following the rules Scrum.  Since then, I’ve done a lot of studying, hands on practice, coaching of many different teams, and other learning around Scrum, and I have discovered that Scrum has some rules that must be followed for success, even though the process is about continuous improvement. I’ve been practicing Scrum right for about 4 years now and have helped multiple teams implement it successfully, so what you’re about to get is based on experience, rather than just theory. The Rules of Scrum In my experience, what I’ve found is that most companies that claim to be doing Scrum or Agile are actually NOT doing either.  This stems largely because they think that they can “adopt the rules of Agile that fit their organization.”  Sadly, many of them think that this means they can adopt iterations (sprints) and not much else.  Either that, or they think they can do whatever they want, or were doing before, and call it Scrum.  This is simply not true. Here are some rules that must be followed for you to really be doing Scrum.  I’ll go into detail on each one of these posts in future blog posts and update links here.  My intent is that this will help other teams implementing scrum to see more success. Agile does not allow you to do whatever you want A Product Owner is required A ScrumMaster is required The team must function as a Team, and QA must be part of the team Support from upper management is required A prioritized product backlog is required A prioritized sprint backlog is required Release planning is required Complete spring planning is required Showcases are required Velocity must be measured Retrospectives are required Daily stand-ups are required Visibility is absolutely required For now, I think that’s enough, although I reserve the right to add more.  If you’re breaking any of these rules, you’re probably not doing Scrum.  There are exceptions to these rules, but until you have practiced Scrum for a while, you don’t know what those exceptions are. Breaking the Rules Many teams break these rules because they are the ones that expose the most pain.  Scrum is not Advil.  It’s not intended to mask the pain, its intended to cure it.  Let me explain that analogy a bit more.  Recently, my 7 year old son broke his arm, quite severely (see the X-Ray to the right).  That caused him a great deal of pain.  We went first to one doctor, and after viewing the X-Ray, they determined that there was no way that they’d cast the arm at their location.  It was simply too bad of a break for them to deal with.  They did, however, give him some Advil for the pain and put a splint on his arm to stabilize the broken bones.  Within minutes, he was feeling much better.  Had we been stupid, we could have gone home and he’d have been just as happy as ever . . . until the pain medication wore off or one of his siblings touched the splint.  Then, all of that pain would come right back to the top.  Sure, he could make it go away by just taking more Advil and moving the splint out of the way, but that wasn’t going to fix the problem permanently. We ended up in an emergency room with a doctor who could fix his arm.  However, we were warned that the fix was going to be VERY painful, and it was.  Even with heavy sedation (Propofol), my son was in enough pain that he squirmed and wiggled trying to get his arm away from the doctor.  He had to endure this pain in order to have a functional arm. But the setting wasn’t the end.  He had to have several casts, had to have it re-broken once, since the first setting didn’t take and finally was given a clean bill of health. Agile implementation is much like this story.  Agile was developed as a result of people recognizing that the development methodologies that were currently in place simply were ineffective.  However, the fix to the broken development that’s been festering for many years is not painless.  Many people start Agile thinking that things will be wonderful.  They won’t!  Agile is about visibility, and often, it brings great pain to surface.  It causes all of the missed deadlines, the cowboy coders, the coasters, the micro-managers, the lazy, and all of the other problems that are really part of your development process now to become painfully visible to EVERYONE.  Many people don’t like this exposure.  Agile will make the pain better, but not if you remove the cast (the rules above) prematurely and start breaking the rules that expose the most pain.  The healing will take time and is not instant (like Advil).  Figuring out what the true source of pain and fixing it is very valuable to you, your team, and your company.  Remember as you’re doing this that Agile isn’t the source of the pain, it’s really just exposing it.  Find the source. My recommendation is that ALL of these rules are followed for a minimum of six months, and preferably for an entire year, before you decide to break any of these rules.  Get a few good releases under your belt.  Figure out what your velocity is and start firing as a team.  Chances are, after you see agile really in action, you won’t want to break the rules because you’ll see their value. More Reading Jean Tabaka recently published a list of 78 Things I Have Learned in 6 Years of Agile Coaching.  Highly recommended. Technorati Tags: Agile,Scrum,Rules

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• Learning AngularJS by Example – The Customer Manager Application

  - by dwahlin

  I’m always tinkering around with different ideas and toward the beginning of 2013 decided to build a sample application using AngularJS that I call Customer Manager. It’s not exactly the most creative name or concept, but I wanted to build something that highlighted a lot of the different features offered by AngularJS and how they could be used together to build a full-featured app. One of the goals of the application was to ensure that it was approachable by people new to Angular since I’ve never found overly complex applications great for learning new concepts. The application initially started out small and was used in my AngularJS in 60-ish Minutes video on YouTube but has gradually had more and more features added to it and will continue to be enhanced over time. It’ll be used in a new “end-to-end” training course my company is working on for AngularjS as well as in some video courses that will be coming out. Here’s a quick look at what the application home page looks like: In this post I’m going to provide an overview about how the application is organized, back-end options that are available, and some of the features it demonstrates. I’ve already written about some of the features so if you’re interested check out the following posts: Building an AngularJS Modal Service Building a Custom AngularJS Unique Value Directive Using an AngularJS Factory to Interact with a RESTful Service Application Structure The structure of the application is shown to the right. The  homepage is index.html and is located at the root of the application folder. It defines where application views will be loaded using the ng-view directive and includes script references to AngularJS, AngularJS routing and animation scripts, plus a few others located in the Scripts folder and to custom application scripts located in the app folder. The app folder contains all of the key scripts used in the application. There are several techniques that can be used for organizing script files but after experimenting with several of them I decided that I prefer things in folders such as controllers, views, services, etc. Doing that helps me find things a lot faster and allows me to categorize files (such as controllers) by functionality. My recommendation is to go with whatever works best for you. Anyone who says, “You’re doing it wrong!” should be ignored. Contrary to what some people think, there is no “one right way” to organize scripts and other files. As long as the scripts make it down to the client properly (you’ll likely minify and concatenate them anyway to reduce bandwidth and minimize HTTP calls), the way you organize them is completely up to you. Here’s what I ended up doing for this application: Animation code for some custom animations is located in the animations folder. In addition to AngularJS animations (which are defined using CSS in Content/animations.css), it also animates the initial customer data load using a 3rd party script called GreenSock. Controllers are located in the controllers folder. Some of the controllers are placed in subfolders based upon the their functionality while others are placed at the root of the controllers folder since they’re more generic:   The directives folder contains the custom directives created for the application. The filters folder contains the custom filters created for the application that filter city/state and product information. The partials folder contains partial views. This includes things like modal dialogs used in the application. The services folder contains AngularJS factories and services used for various purposes in the application. Most of the scripts in this folder provide data functionality. The views folder contains the different views used in the application. Like the controllers folder, the views are organized into subfolders based on their functionality:   Back-End Services The Customer Manager application (grab it from Github) provides two different options on the back-end including ASP.NET Web API and Node.js. The ASP.NET Web API back-end uses Entity Framework for data access and stores data in SQL Server (LocalDb). The other option on the back-end is Node.js, Express, and MongoDB.   Using the ASP.NET Web API Back-End To run the application using ASP.NET Web API/SQL Server back-end open the .sln file at the root of the project in Visual Studio 2012 or higher (the free Express 2013 for Web version is fine). Press F5 and a browser will automatically launch and display the application. Using the Node.js Back-End To run the application using the Node.js/MongoDB back-end follow these steps: In the CustomerManager directory execute 'npm install' to install Express, MongoDB and Mongoose (package.json). Load sample data into MongoDB by performing the following steps: Execute 'mongod' to start the MongoDB daemon Navigate to the CustomerManager directory (the one that has initMongoCustData.js in it) then execute 'mongo' to start the MongoDB shell Enter the following in the mongo shell to load the seed files that handle seeding the database with initial data: use custmgr load("initMongoCustData.js") load("initMongoSettingsData.js") load("initMongoStateData.js") Start the Node/Express server by navigating to the CustomerManager/server directory and executing 'node app.js' View the application at http://localhost:3000 in your browser. Key Features The Customer Manager application certainly doesn’t cover every feature provided by AngularJS (as mentioned the intent was to keep it as simple as possible) but does provide insight into several key areas: Using factories and services as re-useable data services (see the app/services folder) Creating custom directives (see the app/directives folder) Custom paging (see app/views/customers/customers.html and app/controllers/customers/customersController.js) Custom filters (see app/filters) Showing custom modal dialogs with a re-useable service (see app/services/modalService.js) Making Ajax calls using a factory (see app/services/customersService.js) Using Breeze to retrieve and work with data (see app/services/customersBreezeService.js). Switch the application to use the Breeze factory by opening app/services.config.js and changing the useBreeze property to true. Intercepting HTTP requests to display a custom overlay during Ajax calls (see app/directives/wcOverlay.js) Custom animations using the GreenSock library (see app/animations/listAnimations.js) Creating custom AngularJS animations using CSS (see Content/animations.css) JavaScript patterns for defining controllers, services/factories, directives, filters, and more (see any JavaScript file in the app folder) Card View and List View display of data (see app/views/customers/customers.html and app/controllers/customers/customersController.js) Using AngularJS validation functionality (see app/views/customerEdit.html, app/controllers/customerEditController.js, and app/directives/wcUnique.js) More… Conclusion I’ll be enhancing the application even more over time and welcome contributions as well. Tony Quinn contributed the initial Node.js/MongoDB code which is very cool to have as a back-end option. Access the standard application here and a version that has custom routing in it here. Additional information about the custom routing can be found in this post.

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• Flashing your Windows Phone Dummies

  - by Martin Hinshelwood

  The rate at which vendors release new updates for the HD2 is ridiculously slow. You have to wait for Microsoft to release the new OS, then you wait for HTC to build it into a ROM, and then you have to wait up to 6 months for your operator to badly customise it for their network. Once Windows Phone 7 is released this problem should go away as Microsoft is likely to be able to update the phone over the air, but what do we do until then? I want Windows Mobile 6.5.5 now!   I’m an early adopter. If there is a new version of something then that’s the version I want. As long as you accept that you are using something on a “let the early adopter beware” and accept that there may be bugs, sometimes serious crippling bugs the go for it. Note that I won't be responsible if you end up bricking your phone, unlocking or flashing your radio or ROM can be risky. If you follow the instructions then you should be fine, I've flashed my phones (SPV, M300, M1000, M2000, M3100, TyTN, TyTN 2, HD2) hundreds of times without any problems! I have been using Windows Mobile 6.5.5 before it was called 6.5.5 and for long enough that I don’t even remember when I first started using it. I was using it on my HTC TyTN 2 before I got an HD2 a couple of months before Christmas, and the first custom ROM’s for the HD2 were a couple of months after that. I always update to the latest ROM that I like, and occasionally I go back to the stock ROM’s to have a look see, but I am always disappointed. Terms: Soft Reset: Same as pulling out the battery, but is like a reboot for your phone Hard Reset: Reinstalls the Operating system from the Image that is stored on it ROM: This is Image that is loaded onto your phone and it is used to reinstall your phone whenever you do a “hard reset”. Stock ROM: A ROM from the original vendor… So HTC Cook a ROM: Referring to Cooking a ROM is the process a ROM developer goes through to take all of the parts (OS, Drivers and Applications) that make up a running phone and compiling them into a ROM. ROM Kitchen: A place where you get an SDK and all the component parts of the phone: OD, Drivers and Application. There are usually lots of Tools for making it easier to compile and build the image. Flashing: The process of updating one of the layers of your phone with a new layer Bricked: This is what happens when flashing goes wrong. Your phone is now good for only one thing… stopping paper blowing away in a windy place. You can “cook” you own ROM using one of the many good “ROM Kitchens” or you can use a ROM built and tested by someone else. I have cooked my own ROM before, and while the tutorials are good, it is a lot of hassle. You can only Flash new ROM’s that are specifically for your phone only so find a ROM for your phone and XDA Developers is the best place to look. It has a forum based structure and you can find your phone quite easily. XDA Developer Forum Installing a new ROM does have its risks. In the past there have been stories about phones being “bricked” but I have not heard of a bricked phone for quite some years. if you follow the instructions carefully you should not have any problems. note: Most of the tools are written by people for whom English is not their first language to you will need concentrate hard to understand some of the instructions. Have you ever read a manual that was just literally translated from another language? Enough said… There are a number of layers on your phone that you will need to know about: SPL: This is the lowest level, like a BIOS on a PC and is the Operating Systems gateway to the hardware Radio: I think of this as the hardware drivers, and you will need a different Radio for CDMA than GSM networks ROM: This is like your Windows CD, but it is stored internally to the Phone. Flashing your phone consists of replacing one Image with another and then wiping your phone and automatically reinstall from the Image. Sometimes when you download an Image wither it is for a Radio or for ROM you only get a file called *.nbh. What do you do with this? Well you need an RUU application to push that Image to your phone. The RUU’s are different per phone, but there is a CustomRUU for the HD2 that will update your phone with any *.nbh placed in the same directory. Download and Instructions for CustomRUU #1 Flash HardSPL An SPL is kind of like a BIOS, and the default one has checks to make sure that you are only installing a signed ROM. This would prevent you from installing one that comes from any other source but the vendor. NOTE: Installing a HARD SPL invalidates your warranty so remember to Flash your phone with a “stock” vendor ROM before trying to send your phone in for repairs. Is the warranty reinstated when you go back to a stock ROM? I don’t know… Updating your SPL to a HardSPL effectively unlocks your phone so you can install anything you like. I would recommend the HardSPL2. Download and Instructions for HardSPL2 #2 Task29 One of the problems that has been seen on the HD2 when flashing new ROM’s is that things are left over from the old ROM. For a while the recommendation was to Flash a stock ROM first, but some clever cookies have come up with “Task29” which formats your phone first. After running this your phone will be blank and will only boot to the white HTC logo and no further. You should follow the instructions and reboot (remove battery) and hold down the “volume down” button while turning you HD2 on to enter the bootloader. From here you can run CustomRUU once the USB message appears. Download and Instructions for Task29 #2 Flash Radio You may need to play around with this one, there is no good and bad version and the latest is not always the best. You know that annoying thing when you hit “end call” on your phone and nothing happens? Well that's down to the Radio. Get this version right for you and you may even be able to make calls. From a Windows Mobile as well Download There are no instructions here, but they are the same as th ROM, but you use this *.nbh file. #3 Flash ROM If you have gotten this far then you are probably a pro by now Just download the latest ROM below and Flash to your phone. I have been really impressed by the Artemis line of ROM’s but it is no way the only choice. I like this one as the developer builds them as close to the stock ROM as possible while updating to the latest of everything. Download and Instructions for  Artemis HD2 vXX Conclusion While updating your ROM is not for the faint hearted it provides more options than the Stock ROM’s and quicker feature updates than waiting… Technorati Tags: WM6

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• Video on Architecture and Code Quality using Visual Studio 2012&ndash;interview with Marcel de Vries and Terje Sandstrom by Adam Cogan

  - by terje

  Find the video HERE. Adam Cogan did a great Web TV interview with Marcel de Vries and myself on the topics of architecture and code quality.  It was real fun participating in this session.  Although we know each other from the MVP ALM community,  Marcel, Adam and I haven’t worked together before. It was very interesting to see how we agreed on so many terms, and how alike we where thinking.  The basics of ensuring you have a good architecture and how you could document it is one thing.  Also, the same agreement on the importance of having a high quality code base, and how we used the Visual Studio 2012 tools, and some others (NDepend for example)  to measure and ensure that the code quality was where it should be.  As the tools, methods and thinking popped up during the interview it was a lot of “Hey !  I do that too!”.  The tools are not only for “after the fact” work, but we use them during the coding.  That way the tools becomes an integrated part of our coding work, and helps us to find issues we may have overlooked.  The video has a bunch of call outs, pinpointing important things to remember. These are also listed on the corresponding web page. I haven’t seen that touch before, but really liked this way of doing it – it makes it much easier to spot the highlights.  Titus Maclaren and Raj Dhatt from SSW have done a terrific job producing this video.  And thanks to Lei Xu for doing the camera and recording job.  Thanks guys ! Also, if you are at TechEd Amsterdam 2012, go and listen to Adam Cogan in his session on “A modern architecture review: Using the new code review tools” Friday 29th, 10.15-11.30 and Marcel de Vries session on “Intellitrace, what is it and how can I use it to my benefit” Wednesday 27th, 5-6.15 The highlights points out some important practices.  I’ll elaborate on a few of them here: Add instructions on how to compile the solution.  You do this by adding a text file with instructions to the solution, and keep it under source control.  These instructions should contain what is needed on top of a standard install of Visual Studio.  I do a lot of code reviews, and more often that not, I am not even able to compile the program, because they have used some tool or library that needs to be installed.  The same applies to any new developer who enters into the team, so do this to increase your productivity when the team changes, or a team member switches computer. Don’t forget to document what you have to configure on the computer, the IIS being a common one. The more automatic you can do this, the better.  Use NuGet to get down libraries. When the text document gets more than say, half a page, with a bunch of different things to do, convert it into a powershell script instead.  The metrics warning levels.  These are very conservatively set by Microsoft.  You rarely see anything but green, and besides, you should have color scales for each of the metrics.  I have a blog post describing a more appropriate set of levels, based on both research work and industry “best practices”.  The essential limits are: Cyclomatic complexity and coupling:  Higher numbers are worse On method levels: Green :  From 0 to 10 Yellow:  From 10 to 20  (some say 15).   Acceptable, but have a look to see if there is something unneeded here. Red: From 20 to 40:   Action required, get these down. Bleeding Red: Above 40   This is the real red alert.  Immediate action!  (My invention, as people have asked what do I do when I have cyclomatic complexity of 150.  The only answer I could think of was: RUN! ) Maintainability index:  Lower numbers are worse, scale from 0 to 100. On method levels: Green:  60 to 100 Yellow:  40 – 60.    You will always have methods here too, accept the higher ones, take a look at those who are down to the lower limit.  Check up against the other metrics.) Red:  20 – 40:  Action required, fix these. Bleeding red:  Below 20.  Immediate action required. When doing metrics analysis, you should leave the generated code out.  You do this by adding attributes, unfortunately Microsoft has “forgotten” to add these to all their stuff, so you might have to add them to some of the code.  It most cases it can be done so that it is not overwritten by a new round of code generation.  Take a look a my blog post here for details on how to do that. Class level metrics might also be useful, at least for coupling and maintenance.  But it is much more difficult to set any fixed limits on those.  Any metric aggregations on higher level tend to be pretty useless, as the number of methods vary pretty much, and there are little science on what number of methods can be regarded as good or bad.  NDepend have a recommendation, but they say it may vary too.  And in these days of data binding, the number might be pretty high, as properties counts as methods.  However, if you take the worst case situations, classes with more than 20 methods are suspicious, and coupling and cyclomatic complexity go red above 20, so any classes with more than 20x20 = 400 for these measures should be checked over. In the video we mention the SOLID principles, coined by “Uncle Bob” (Richard Martin). One of them, the Dependency Inversion principle we discuss in the video.  It is important to note that this principle is NOT on whether you should use a Dependency Inversion Container or not, it is about how you design the interfaces and interactions between your classes.  The Dependency Inversion Container is just one technique which is based on this principle, but which main purpose is to isolate things you would like to change at runtime, for example if you implement a plug in architecture.  Overuse of a Dependency Inversion Container is however, NOT a good thing.  It should be used for a purpose and not as a general DI solution.  The general DI solution and thinking however is useful far beyond the DIC.   You should always “program to an abstraction”, and not to the concreteness.  We also talk a bit about the GRASP patterns, a term coined by Craig Larman in his book Applying UML and design patterns. GRASP patterns stand for General Responsibility Assignment Software Patterns and describe fundamental principles of object design and responsibility assignment.  What I find great with these patterns is that they is another way to focus on the responsibility of a class.  One of the things I most often found that is broken in software designs, is that the class lack responsibility, and as a result there are a lot of classes mucking around in the internals of the other classes.  We also discuss the term “Code Smells”.  This term was invented by Kent Beck and Martin Fowler when they worked with Fowler’s “Refactoring” book. A code smell is a set of “bad” coding practices, which are the drivers behind a corresponding set of refactorings.  Here is a good list of the smells, and their corresponding refactor patterns. See also this.

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• European Interoperability Framework - a new beginning?

  - by trond-arne.undheim

  The most controversial document in the history of the European Commission's IT policy is out. EIF is here, wrapped in the Communication "Towards interoperability for European public services", and including the new feature European Interoperability Strategy (EIS), arguably a higher strategic take on the same topic. Leaving EIS aside for a moment, the EIF controversy has been around IPR, defining open standards and about the proper terminology around standardization deliverables. Today, as the document finally emerges, what is the verdict? First of all, to be fair to those among you who do not spend your lives in the intricate labyrinths of Commission IT policy documents on interoperability, let's define what we are talking about. According to the Communication: "An interoperability framework is an agreed approach to interoperability for organisations that want to collaborate to provide joint delivery of public services. Within its scope of applicability, it specifies common elements such as vocabulary, concepts, principles, policies, guidelines, recommendations, standards, specifications and practices." The Good - EIF reconfirms that "The Digital Agenda can only take off if interoperability based on standards and open platforms is ensured" and also confirms that "The positive effect of open specifications is also demonstrated by the Internet ecosystem." - EIF takes a productive and pragmatic stance on openness: "In the context of the EIF, openness is the willingness of persons, organisations or other members of a community of interest to share knowledge and stimulate debate within that community, the ultimate goal being to advance knowledge and the use of this knowledge to solve problems" (p.11). "If the openness principle is applied in full: - All stakeholders have the same possibility of contributing to the development of the specification and public review is part of the decision-making process; - The specification is available for everybody to study; - Intellectual property rights related to the specification are licensed on FRAND terms or on a royalty-free basis in a way that allows implementation in both proprietary and open source software" (p. 26). - EIF is a formal Commission document. The former EIF 1.0 was a semi-formal deliverable from the PEGSCO, a working group of Member State representatives. - EIF tackles interoperability head-on and takes a clear stance: "Recommendation 22. When establishing European public services, public administrations should prefer open specifications, taking due account of the coverage of functional needs, maturity and market support." - The Commission will continue to support the National Interoperability Framework Observatory (NIFO), reconfirming the importance of coordinating such approaches across borders. - The Commission will align its internal interoperability strategy with the EIS through the eCommission initiative. - One cannot stress the importance of using open standards enough, whether in the context of open source or non-open source software. The EIF seems to have picked up on this fact: What does the EIF says about the relation between open specifications and open source software? The EIF introduces, as one of the characteristics of an open specification, the requirement that IPRs related to the specification have to be licensed on FRAND terms or on a royalty-free basis in a way that allows implementation in both proprietary and open source software. In this way, companies working under various business models can compete on an equal footing when providing solutions to public administrations while administrations that implement the standard in their own software (software that they own) can share such software with others under an open source licence if they so decide. - EIF is now among the center pieces of the Digital Agenda (even though this demands extensive inter-agency coordination in the Commission): "The EIS and the EIF will be maintained under the ISA Programme and kept in line with the results of other relevant Digital Agenda actions on interoperability and standards such as the ones on the reform of rules on implementation of ICT standards in Europe to allow use of certain ICT fora and consortia standards, on issuing guidelines on essential intellectual property rights and licensing conditions in standard-setting, including for ex-ante disclosure, and on providing guidance on the link between ICT standardisation and public procurement to help public authorities to use standards to promote efficiency and reduce lock-in.(Communication, p.7)" All in all, quite a few good things have happened to the document in the two years it has been on the shelf or was being re-written, depending on your perspective, in any case, awaiting the storms to calm. The Bad - While a certain pragmatism is required, and governments cannot migrate to full openness overnight, EIF gives a bit too much room for governments not to apply the openness principle in full. Plenty of reasons are given, which should maybe have been put as challenges to be overcome: "However, public administrations may decide to use less open specifications, if open specifications do not exist or do not meet functional interoperability needs. In all cases, specifications should be mature and sufficiently supported by the market, except if used in the context of creating innovative solutions". - EIF does not use the internationally established terminology: open standards. Rather, the EIF introduces the notion of "formalised specification". How do "formalised specifications" relate to "standards"? According to the FAQ provided: The word "standard" has a specific meaning in Europe as defined by Directive 98/34/EC. Only technical specifications approved by a recognised standardisation body can be called a standard. Many ICT systems rely on the use of specifications developed by other organisations such as a forum or consortium. The EIF introduces the notion of "formalised specification", which is either a standard pursuant to Directive 98/34/EC or a specification established by ICT fora and consortia. The term "open specification" used in the EIF, on the one hand, avoids terminological confusion with the Directive and, on the other, states the main features that comply with the basic principle of openness laid down in the EIF for European Public Services. Well, this may be somewhat true, but in reality, Europe is 30 year behind in terminology. Unless the European Standardization Reform gets completed in the next few months, most Member States will likely conclude that they will go on referencing and using standards beyond those created by the three European endorsed monopolists of standardization, CEN, CENELEC and ETSI. Who can afford to begin following the strict Brussels rules for what they can call open standards when, in reality, standards stemming from global standardization organizations, so-called fora/consortia, dominate in the IT industry. What exactly is EIF saying? Does it encourage Member States to go on using non-ESO standards as long as they call it something else? I guess I am all for it, although it is a bit cumbersome, no? Why was there so much interest around the EIF? The FAQ attempts to explain: Some Member States have begun to adopt policies to achieve interoperability for their public services. These actions have had a significant impact on the ecosystem built around the provision of such services, e.g. providers of ICT goods and services, standardisation bodies, industry fora and consortia, etc... The Commission identified a clear need for action at European level to ensure that actions by individual Member States would not create new electronic barriers that would hinder the development of interoperable European public services. As a result, all stakeholders involved in the delivery of electronic public services in Europe have expressed their opinions on how to increase interoperability for public services provided by the different public administrations in Europe. Well, it does not take two years to read 50 consultation documents, and the EU Standardization Reform is not yet completed, so, more pragmatically, you finally had to release the document. Ok, let's leave some of that aside because the document is out and some people are happy (and others definitely not). The Verdict Considering the controversy, the delays, the lobbying, and the interests at stake both in the EU, in Member States and among vendors large and small, this document is pretty impressive. As with a good wine that has not yet come to full maturity, let's say that it seems to be coming in in the 85-88/100 range, but only a more fine-grained analysis, enjoyment in good company, and ultimately, implementation, will tell. The European Commission has today adopted a significant interoperability initiative to encourage public administrations across the EU to maximise the social and economic potential of information and communication technologies. Today, we should rally around this achievement. Tomorrow, let's sit down and figure out what it means for the future.

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• Of C# Iterators and Performance

  - by James Michael Hare

  Some of you reading this will be wondering, "what is an iterator" and think I'm locked in the world of C++.  Nope, I'm talking C# iterators.  No, not enumerators, iterators.   So, for those of you who do not know what iterators are in C#, I will explain it in summary, and for those of you who know what iterators are but are curious of the performance impacts, I will explore that as well.   Iterators have been around for a bit now, and there are still a bunch of people who don't know what they are or what they do.  I don't know how many times at work I've had a code review on my code and have someone ask me, "what's that yield word do?"   Basically, this post came to me as I was writing some extension methods to extend IEnumerable<T> -- I'll post some of the fun ones in a later post.  Since I was filtering the resulting list down, I was using the standard C# iterator concept; but that got me wondering: what are the performance implications of using an iterator versus returning a new enumeration?   So, to begin, let's look at a couple of methods.  This is a new (albeit contrived) method called Every(...).  The goal of this method is to access and enumeration and return every nth item in the enumeration (including the first).  So Every(2) would return items 0, 2, 4, 6, etc.   Now, if you wanted to write this in the traditional way, you may come up with something like this:       public static IEnumerable<T> Every<T>(this IEnumerable<T> list, int interval)     {         List<T> newList = new List<T>();         int count = 0;           foreach (var i in list)         {             if ((count++ % interval) == 0)             {                 newList.Add(i);             }         }           return newList;     }     So basically this method takes any IEnumerable<T> and returns a new IEnumerable<T> that contains every nth item.  Pretty straight forward.   The problem?  Well, Every<T>(...) will construct a list containing every nth item whether or not you care.  What happens if you were searching this result for a certain item and find that item after five tries?  You would have generated the rest of the list for nothing.   Enter iterators.  This C# construct uses the yield keyword to effectively defer evaluation of the next item until it is asked for.  This can be very handy if the evaluation itself is expensive or if there's a fair chance you'll never want to fully evaluate a list.   We see this all the time in Linq, where many expressions are chained together to do complex processing on a list.  This would be very expensive if each of these expressions evaluated their entire possible result set on call.    Let's look at the same example function, this time using an iterator:       public static IEnumerable<T> Every<T>(this IEnumerable<T> list, int interval)     {         int count = 0;         foreach (var i in list)         {             if ((count++ % interval) == 0)             {                 yield return i;             }         }     }   Notice it does not create a new return value explicitly, the only evidence of a return is the "yield return" statement.  What this means is that when an item is requested from the enumeration, it will enter this method and evaluate until it either hits a yield return (in which case that item is returned) or until it exits the method or hits a yield break (in which case the iteration ends.   Behind the scenes, this is all done with a class that the CLR creates behind the scenes that keeps track of the state of the iteration, so that every time the next item is asked for, it finds that item and then updates the current position so it knows where to start at next time.   It doesn't seem like a big deal, does it?  But keep in mind the key point here: it only returns items as they are requested. Thus if there's a good chance you will only process a portion of the return list and/or if the evaluation of each item is expensive, an iterator may be of benefit.   This is especially true if you intend your methods to be chainable similar to the way Linq methods can be chained.    For example, perhaps you have a List<int> and you want to take every tenth one until you find one greater than 10.  We could write that as:       List<int> someList = new List<int>();         // fill list here         someList.Every(10).TakeWhile(i => i <= 10);     Now is the difference more apparent?  If we use the first form of Every that makes a copy of the list.  It's going to copy the entire list whether we will need those items or not, that can be costly!    With the iterator version, however, it will only take items from the list until it finds one that is > 10, at which point no further items in the list are evaluated.   So, sounds neat eh?  But what's the cost is what you're probably wondering.  So I ran some tests using the two forms of Every above on lists varying from 5 to 500,000 integers and tried various things.    Now, iteration isn't free.  If you are more likely than not to iterate the entire collection every time, iterator has some very slight overhead:   Copy vs Iterator on 100% of Collection (10,000 iterations) Collection Size Num Iterated Type Total ms 5 5 Copy 5 5 5 Iterator 5 50 50 Copy 28 50 50 Iterator 27 500 500 Copy 227 500 500 Iterator 247 5000 5000 Copy 2266 5000 5000 Iterator 2444 50,000 50,000 Copy 24,443 50,000 50,000 Iterator 24,719 500,000 500,000 Copy 250,024 500,000 500,000 Iterator 251,521   Notice that when iterating over the entire produced list, the times for the iterator are a little better for smaller lists, then getting just a slight bit worse for larger lists.  In reality, given the number of items and iterations, the result is near negligible, but just to show that iterators come at a price.  However, it should also be noted that the form of Every that returns a copy will have a left-over collection to garbage collect.   However, if we only partially evaluate less and less through the list, the savings start to show and make it well worth the overhead.  Let's look at what happens if you stop looking after 80% of the list:   Copy vs Iterator on 80% of Collection (10,000 iterations) Collection Size Num Iterated Type Total ms 5 4 Copy 5 5 4 Iterator 5 50 40 Copy 27 50 40 Iterator 23 500 400 Copy 215 500 400 Iterator 200 5000 4000 Copy 2099 5000 4000 Iterator 1962 50,000 40,000 Copy 22,385 50,000 40,000 Iterator 19,599 500,000 400,000 Copy 236,427 500,000 400,000 Iterator 196,010       Notice that the iterator form is now operating quite a bit faster.  But the savings really add up if you stop on average at 50% (which most searches would typically do):     Copy vs Iterator on 50% of Collection (10,000 iterations) Collection Size Num Iterated Type Total ms 5 2 Copy 5 5 2 Iterator 4 50 25 Copy 25 50 25 Iterator 16 500 250 Copy 188 500 250 Iterator 126 5000 2500 Copy 1854 5000 2500 Iterator 1226 50,000 25,000 Copy 19,839 50,000 25,000 Iterator 12,233 500,000 250,000 Copy 208,667 500,000 250,000 Iterator 122,336   Now we see that if we only expect to go on average 50% into the results, we tend to shave off around 40% of the time.  And this is only for one level deep.  If we are using this in a chain of query expressions it only adds to the savings.   So my recommendation?  If you have a resonable expectation that someone may only want to partially consume your enumerable result, I would always tend to favor an iterator.  The cost if they iterate the whole thing does not add much at all -- and if they consume only partially, you reap some really good performance gains.   Next time I'll discuss some of my favorite extensions I've created to make development life a little easier and maintainability a little better.

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• Windows Azure Virtual Machine Readiness and Capacity Assessment for SQL Server

  - by SQLOS Team

  Windows Azure Virtual Machine Readiness and Capacity Assessment for Windows Server Machine Running SQL Server With the release of MAP Toolkit 8.0 Beta, we have added a new scenario to assess your Windows Azure Virtual Machine Readiness. The MAP 8.0 Beta performs a comprehensive assessment of Windows Servers running SQL Server to determine you level of readiness to migrate an on-premise physical or virtual machine to Windows Azure Virtual Machines. The MAP Toolkit then offers suggested changes to prepare the machines for migration, such as upgrading the operating system or SQL Server. MAP Toolkit 8.0 Beta is available for download here Your participation and feedback is very important to make the MAP Toolkit work better for you. We encourage you to participate in the beta program and provide your feedback at [email protected] or through one of our surveys. Now, let’s walk through the MAP Toolkit task for completing the Windows Azure Virtual Machine assessment and capacity planning. The tasks include the following: Perform an inventory View the Windows Azure VM Readiness results and report Collect performance data for determine VM sizing View the Windows Azure Capacity results and report Perform an inventory: 1. To perform an inventory against a single machine or across a complete environment, choose Perform an Inventory to launch the Inventory and Assessment Wizard as shown below: 2. After the Inventory and Assessment Wizard launches, select either the Windows computers or SQL Server scenario to inventory Windows machines. HINT: If you don’t care about completely inventorying a machine, just select the SQL Server scenario. Click Next to Continue. 3. On the Discovery Methods page, select how you want to discover computers and then click Next to continue. Description of Discovery Methods: Use Active Directory Domain Services -- This method allows you to query a domain controller via the Lightweight Directory Access Protocol (LDAP) and select computers in all or specific domains, containers, or OUs. Use this method if all computers and devices are in AD DS. Windows networking protocols --  This method uses the WIN32 LAN Manager application programming interfaces to query the Computer Browser service for computers in workgroups and Windows NT 4.0–based domains. If the computers on the network are not joined to an Active Directory domain, use only the Windows networking protocols option to find computers. System Center Configuration Manager (SCCM) -- This method enables you to inventory computers managed by System Center Configuration Manager (SCCM). You need to provide credentials to the System Center Configuration Manager server in order to inventory the managed computers. When you select this option, the MAP Toolkit will query SCCM for a list of computers and then MAP will connect to these computers. Scan an IP address range -- This method allows you to specify the starting address and ending address of an IP address range. The wizard will then scan all IP addresses in the range and inventory only those computers. Note: This option can perform poorly, if many IP addresses aren’t being used within the range. Manually enter computer names and credentials -- Use this method if you want to inventory a small number of specific computers. Import computer names from a files -- Using this method, you can create a text file with a list of computer names that will be inventoried. 4. On the All Computers Credentials page, enter the accounts that have administrator rights to connect to the discovered machines. This does not need to a domain account, but needs to be a local administrator. I have entered my domain account that is an administrator on my local machine. Click Next after one or more accounts have been added. NOTE: The MAP Toolkit primarily uses Windows Management Instrumentation (WMI) to collect hardware, device, and software information from the remote computers. In order for the MAP Toolkit to successfully connect and inventory computers in your environment, you have to configure your machines to inventory through WMI and also allow your firewall to enable remote access through WMI. The MAP Toolkit also requires remote registry access for certain assessments. In addition to enabling WMI, you need accounts with administrative privileges to access desktops and servers in your environment. 5. On the Credentials Order page, select the order in which want the MAP Toolkit to connect to the machine and SQL Server. Generally just accept the defaults and click Next. 6. On the Enter Computers Manually page, click Create to pull up at dialog to enter one or more computer names. 7. On the Summary page confirm your settings and then click Finish. After clicking Finish the inventory process will start, as shown below: Windows Azure Readiness results and report After the inventory progress has completed, you can review the results under the Database scenario. On the tile, you will see the number of Windows Server machine with SQL Server that were analyzed, the number of machines that are ready to move without changes and the number of machines that require further changes. If you click this Azure VM Readiness tile, you will see additional details and can generate the Windows Azure VM Readiness Report. After the report is generated, select View | Saved Reports and Proposals to view the location of the report. Open up WindowsAzureVMReadiness* report in Excel. On the Windows tab, you can see the results of the assessment. This report has a column for the Operating System and SQL Server assessment and provides a recommendation on how to resolve, if there a component is not supported. Collect Performance Data Launch the Performance Wizard to collect performance information for the Windows Server machines that you would like the MAP Toolkit to suggest a Windows Azure VM size for. Windows Azure Capacity results and report After the performance metrics are collected, the Azure VM Capacity title will display the number of Virtual Machine sizes that are suggested for the Windows Server and Linux machines that were analyzed. You can then click on the Azure VM Capacity tile to see the capacity details and generate the Windows Azure VM Capacity Report. Within this report, you can view the performance data that was collected and the Virtual Machine sizes.   MAP Toolkit 8.0 Beta is available for download here Your participation and feedback is very important to make the MAP Toolkit work better for you. We encourage you to participate in the beta program and provide your feedback at [email protected] or through one of our surveys. Useful References: Windows Azure Homepage How to guides for Windows Azure Virtual Machines Provisioning a SQL Server Virtual Machine on Windows Azure Windows Azure Pricing     Peter Saddow Senior Program Manager – MAP Toolkit Team

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• WebSocket Applications using Java: JSR 356 Early Draft Now Available (TOTD #183)

  - by arungupta

  WebSocket provide a full-duplex and bi-directional communication protocol over a single TCP connection. JSR 356 is defining a standard API for creating WebSocket applications in the Java EE 7 Platform. This Tip Of The Day (TOTD) will provide an introduction to WebSocket and how the JSR is evolving to support the programming model. First, a little primer on WebSocket! WebSocket is a combination of IETF RFC 6455 Protocol and W3C JavaScript API (still a Candidate Recommendation). The protocol defines an opening handshake and data transfer. The API enables Web pages to use the WebSocket protocol for two-way communication with the remote host. Unlike HTTP, there is no need to create a new TCP connection and send a chock-full of headers for every message exchange between client and server. The WebSocket protocol defines basic message framing, layered over TCP. Once the initial handshake happens using HTTP Upgrade, the client and server can send messages to each other, independent from the other. There are no pre-defined message exchange patterns of request/response or one-way between client and and server. These need to be explicitly defined over the basic protocol. The communication between client and server is pretty symmetric but there are two differences: A client initiates a connection to a server that is listening for a WebSocket request. A client connects to one server using a URI. A server may listen to requests from multiple clients on the same URI. Other than these two difference, the client and server behave symmetrically after the opening handshake. In that sense, they are considered as "peers". After a successful handshake, clients and servers transfer data back and forth in conceptual units referred as "messages". On the wire, a message is composed of one or more frames. Application frames carry payload intended for the application and can be text or binary data. Control frames carry data intended for protocol-level signaling. Now lets talk about the JSR! The Java API for WebSocket is worked upon as JSR 356 in the Java Community Process. This will define a standard API for building WebSocket applications. This JSR will provide support for: Creating WebSocket Java components to handle bi-directional WebSocket conversations Initiating and intercepting WebSocket events Creation and consumption of WebSocket text and binary messages The ability to define WebSocket protocols and content models for an application Configuration and management of WebSocket sessions, like timeouts, retries, cookies, connection pooling Specification of how WebSocket application will work within the Java EE security model Tyrus is the Reference Implementation for JSR 356 and is already integrated in GlassFish 4.0 Promoted Builds. And finally some code! The API allows to create WebSocket endpoints using annotations and interface. This TOTD will show a simple sample using annotations. A subsequent blog will show more advanced samples. A POJO can be converted to a WebSocket endpoint by specifying @WebSocketEndpoint and @WebSocketMessage. @WebSocketEndpoint(path="/hello")public class HelloBean {     @WebSocketMessage    public String sayHello(String name) {         return "Hello " + name + "!";     }} @WebSocketEndpoint marks this class as a WebSocket endpoint listening at URI defined by the path attribute. The @WebSocketMessage identifies the method that will receive the incoming WebSocket message. This first method parameter is injected with payload of the incoming message. In this case it is assumed that the payload is text-based. It can also be of the type byte[] in case the payload is binary. A custom object may be specified if decoders attribute is specified in the @WebSocketEndpoint. This attribute will provide a list of classes that define how a custom object can be decoded. This method can also take an optional Session parameter. This is injected by the runtime and capture a conversation between two endpoints. The return type of the method can be String, byte[] or a custom object. The encoders attribute on @WebSocketEndpoint need to define how a custom object can be encoded. The client side is an index.jsp with embedded JavaScript. The JSP body looks like: <div style="text-align: center;"> <form action="">     <input onclick="say_hello()" value="Say Hello" type="button">         <input id="nameField" name="name" value="WebSocket" type="text"><br>    </form> </div> <div id="output"></div> The code is relatively straight forward. It has an HTML form with a button that invokes say_hello() method and a text field named nameField. A div placeholder is available for displaying the output. Now, lets take a look at some JavaScript code: <script language="javascript" type="text/javascript"> var wsUri = "ws://localhost:8080/HelloWebSocket/hello";     var websocket = new WebSocket(wsUri);     websocket.onopen = function(evt) { onOpen(evt) };     websocket.onmessage = function(evt) { onMessage(evt) };     websocket.onerror = function(evt) { onError(evt) };     function init() {         output = document.getElementById("output");     }     function say_hello() {      websocket.send(nameField.value);         writeToScreen("SENT: " + nameField.value);     } This application is deployed as "HelloWebSocket.war" (download here) on GlassFish 4.0 promoted build 57. So the WebSocket endpoint is listening at "ws://localhost:8080/HelloWebSocket/hello". A new WebSocket connection is initiated by specifying the URI to connect to. The JavaScript API defines callback methods that are invoked when the connection is opened (onOpen), closed (onClose), error received (onError), or a message from the endpoint is received (onMessage). The client API has several send methods that transmit data over the connection. This particular script sends text data in the say_hello method using nameField's value from the HTML shown earlier. Each click on the button sends the textbox content to the endpoint over a WebSocket connection and receives a response based upon implementation in the sayHello method shown above. How to test this out ? Download the entire source project here or just the WAR file. Download GlassFish4.0 build 57 or later and unzip. Start GlassFish as "asadmin start-domain". Deploy the WAR file as "asadmin deploy HelloWebSocket.war". Access the application at http://localhost:8080/HelloWebSocket/index.jsp. After clicking on "Say Hello" button, the output would look like: Here are some references for you: WebSocket - Protocol and JavaScript API JSR 356: Java API for WebSocket - Specification (Early Draft) and Implementation (already integrated in GlassFish 4 promoted builds) Subsequent blogs will discuss the following topics (not necessary in that order) ... Binary data as payload Custom payloads using encoder/decoder Error handling Interface-driven WebSocket endpoint Java client API Client and Server configuration Security Subprotocols Extensions Other topics from the API Capturing WebSocket on-the-wire messages

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