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Tasks Affinity - RRS feed

  • Question

  • Hi all , 

    I'm using Windows HPC 2008 R2 Sp4 .

    We have a client software that submits jobs to Windows HPC via C# API's . 

    Most of the jobs are paramtric sweep - each job can contain 50 to 400 tasks .

    Latetly we saw somthing strange - all the tasks must end the calculation time at the same time (40-50 sec) - but a few tasks finish thier jobs 10 - 20 sec later .

    After fast investigation we saw that one of the nodes cores (Core#15) 20%-30% busy when the compute node is idle .

    When that core computes the task it finish 10 - 20 sec later than each other core .

    I have the following questions :

    - What make that core busy ?

    - Why on all the nodes it core #15 ? 

    - Can I set my tasks affinity not to use core #15 ? 

    - Can I make the scheduler not to allocate taks for that core ? 

    Thanking you in advance , 

    Shai .


    Wednesday, November 21, 2012 9:34 AM

All replies

  • Hi,

    To answer your questions,

    - What make that core busy ?

    you may use the taskmgr->Processes to check what process is running that take the CPU. if you find some suspicious process, right click it, choose "set affinity", it should show which CORE the process is using. This way you can find what is using core 15.

    - Why on all the nodes it core #15 ? 

    I don't know. Please try the approach above to find the process first.

    - Can I set my tasks affinity not to use core #15 ? 

    I am not aware of a way to do this.

    - Can I make the scheduler not to allocate taks for that core ? 

    I am not aware of a way to do this.

    Hope this helps

    Liwei

    Tuesday, January 8, 2013 5:34 PM
  • Hi , 

    Sorry , it was not Windows HPC issue , it was HW problem , core#15 was busy in handling Hardware Interrupts and DPCs  .

    That issue solved by USB drivers upgrade .

    Wednesday, January 9, 2013 9:45 AM