0 Replies Latest reply on Feb 28, 2017 7:16 AM by Grzesiekk

    Numa Disabled ?

    Grzesiekk Expert

      Hello all,

      i have a question regarding the numa. I have a red hat vm ( 5.10 ) , configured right now with 16 vcpu ( 16 sockets , 1 core ).

      I have enabled Hot Add memory and Hot Add cpu.

      in vmware.log for the vm i see:

      2017-02-28T14:24:54.604Z| vmx| NUMA and VCPU hot add are incompatible.  Forcing UMA

      so am i correct that in esxtop i should see unnder NHN  -    ?  Right now i see there 0,1

      What is more inside the guest i can run numactl and i see this :

      img78.png

      And now i am bit confused. As per KB:

      vNUMA is disabled if VCPU hotplug is enabled (2040375) | VMware KB

       

      Since i have enabled the memory and cpu hot add, i should not see any numa, Numactl says that it has 3 nodes. So now i am even more confused, as in esxtop there visible NHN : 0,1  .

      Can somebody correct me in my thinking ?

      In ESXTOP present 2 numa nodes, since i have 2 CPU sockets, each with 6 cores , with ht its 12 logical cpu per socket.

      esxcli hardware memory get | grep -i numa

         NUMA Node Count: 2

       

      Why in guest o/s i see 3 numa nodes ? First this is that i would expect to see 2, but since the hotplug is turned on , i would expect to see  none ?

       

      If i change the number of vcpu in VM to 12 , then numactl is reporting 2 nodes .

       

      Any chance , somebody could explain this to me, or point me to some documentation that explain this in detail ?

       

      Many thanks.