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VSTestHost vs Test Agent RRS feed

  • Question

  • Hi,

    I'm attempting to load test WCF services using unit tests on Visual Studio 2008 RTM.
    The tests are run on a Windows Server 2008 RTM x64 box with 2 quad core Xeon E5430 CPUs and 16Gb of RAM. The WCF services are hosted by IIS on a separate similarly configured server. Server GC is enabled.

    The unit test being run is a call to a "ping" operation on the service, using the generated service reference.

    Using VSTestHost, one core on the client immediately goes to 100% usage and stays there, and no other cores are used. Network traffic and load on the service server is low even when the number of users ramps up to 1000. The .NET contention rate is up to 70, and the .NET queue length is also about 70. An average of 40 tests / second is reached.

    Running on a Test Agent on the local machine the load is spread across all CPUs. An average of 130 tests/second is reached.

    Is there meant to be such a large difference between running under VSTestHost and using an Agent? How should I configure VSTestHost to best use the available resources?

    Simon Taylor.
    Sunday, April 6, 2008 11:07 AM

Answers

  • Yes, the VSTestHost process in VSTS 2008 is limited to using one processor when running a load test.   The load test agent should be purchased to utilize multiple processors.

    Monday, April 7, 2008 1:54 PM
    Moderator

All replies

  • Yes, the VSTestHost process in VSTS 2008 is limited to using one processor when running a load test.   The load test agent should be purchased to utilize multiple processors.

    Monday, April 7, 2008 1:54 PM
    Moderator
  • Is the load test agent licensed per machine, per physical processor, or per logical processor?
    In other words, with a quad core, would I need 4 licenses or just 1?

    Thanks,
    ~Alan
    Wednesday, October 8, 2008 6:19 PM