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  1. OpenShift Virtualization
  2. CNV-52247

IO tests with CNV VM show bigger netowrk latency than tests executed inside pods

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      Description of problem:

      IO tests with CNV VM shows bigger netowrk latency than tests executed inside pods.
      
      OpenShift version: 4.16.9 
      OpenShift Virtualization           4.16.4 
      
      We ran fio inside vm  in first case and inside pod for second case, below are test results 
      
      vm case :
      
      iops: 110 ( bs 4k , but similar situation  for other block sizes ... )
      latency: 9083463 ( us ) ~ 9s
      
      pod case :
      iops: 758 ( bs 4k )
      latency: 1316564 ( us ) ~ 1.3s 
      
      fio job: randwrite, filsize=10GB, ioengine=libaio, bs=4k, iodepth=1, numjobs=10, time_based=1
      
      Version-Release number of selected component (if applicable):
      OpenShift version: 4.16.9 and OpenShift Virtualization 4.16.4 

      How reproducible:

      Always in our testing. 

      Steps to Reproduce:

      Get CNV environment, test IO inside VM and inside pod when both VMs and Pods are using same storage class - it should not matter what storage class is in my opinion. Test at least 10 fio clients. Compare results. 
      We ( perf / scale ) team have working cluster in place which can be used for bz verification. We are also ready and will help with testing. Please let us know.  

      Actual results:

       

      Expected results:

       

      Additional info:

       

              ehaas1@redhat.com Edward Haas
              rhn-support-ekuric Elvir Kuric
              Yoss Segev Yoss Segev
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                Created:
                Updated:
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