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Windows Azure Learning Plan for Exam 70-583

-updated, June 28, 2012

On February 15, 2011, Microsoft made the MCPD (Microsoft Certified Professional Developer) certification for Azure available by releasing Exam 70-583 (PRO: Designing and Developing Windows Azure Applications).

As with any certification exam, preparation resources can be pretty tough to find.  Microsoft has supplied a “Learning Plan” for preparation for this exam.  As a caveat, I must admit that this “learning plan” isn’t that great for exam preparation.  It mostly walks you through a bunch of Channel 9 type presentations on high-level Azure topics.  It is, however, fun to watch the presenters argue and get annoyed with each other in the presentations.  That alone makes it worthy of a look.

You can find it at: 

http://learning.microsoft.com/manager/LearningPlanV2.aspx?resourceId=30f78dea-f126-4b01-82eb-52cbc908e4ec&clang=en-US&cats=d4e8e42c-3d5a-4a6e-915d-d99556a49bd7

A better resource would be Hay and Prince’s Azure in Action, although this is a bit out-dated now.  Finding an “up to date” resource can be pretty tough regardless, as Azure is always changing and I hear the test writers have been actively updating the exam.

AppFabric Caching Tip: Watch Your Memory Usage

Caching uses memory.  Depending on how things are set up and how much data is stored, your caching structure can use up quite a bit of RAM. 

AppFabric Caching is no different.

One fairly common development scenario is when you run SQL Server on the same machine as AppFabric.  On rare occasion, this may result in memory problems as SQL Server has the tendency to  hold onto memory once it’s acquired.  I imagine a conversation between a Windows Server and SQL Server would go something like this:

Windows Server:  Hey, SQL Server, how much memory do you need?
SQL Server:  How much have you got?

You can control how much memory is used through configuration but a SQL Server in its default configuration, as most developers use it, may create issues.

Sometimes you may see an exception like this:  Microsoft.ApplicationServer.Caching.DataCacheException: ErrorCode<ERRCA0017>:SubStatus<ES0007>:There is a temporary failure. Please retry later. (The request failed because the server is in throttled state.)

 You can use Get-CacheClusterHealth command in PowerShell to check the status of your Caching cluster.  Here’s an example of the output for a healthy cluster:

If there are memory issues, you will often see a value other than zero in the Throttled line.

Since caching relies on availability of system memory, it’s a good idea to watch memory usage and try to control how much is used by applications such as SQL Server.

Here’s an MSDN article regarding troubleshooting throttling issues: http://msdn.microsoft.com/en-us/library/ff921030.aspx

Referencing AppFabric Assemblies in Visual Studio on x64 Systems

Adding a reference to a project in Visual Studio should be a fairly simple thing to do.  Right?

Not always.  When working with Windows Server AppFabric you might have a problem if you’re using 64-bit Windows.  Many of the assemblies you use for AppFabric are located in the %WinDir%\System32\AppFabric directory. Unfortunately, this directory is not visible when using the “Add Reference” dialog in Visual Studio.

See? No AppFabric folder…

Fortunately, there’s a work-around. Instead of drilling down to System32, just open up the Add Reference dialog, click on Browse and type or paste %WinDir%\SysNative\AppFabric into the File Name box and type a back-slash (“\”) at the end. You’ll then see a full list of files in the directory.

Just select the assembly you need to reference from the list.

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