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[Jon Grimm <jgrimm@xxxxxxxxxxxxxxxxxx>]

Hi there.    You didn't actually setup a configuration that would create
a VM with threads which was the condition I wrote the bug against.

"  smp 3,sockets=3,cores=1,threads=1 "

Thanks!

** Changed in: nova
       Status: Invalid => New

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https://bugs.launchpad.net/bugs/1355921

Title:
  [libvirt] When guest configured for threads, poor VCPU accounting

Status in OpenStack Compute (Nova):
  New

Bug description:
  Noticed while testing:  https://blueprints.launchpad.net/nova/+spec
  /virt-driver-vcpu-topology

  
  I have a host advertising 16 VCPUs (2 sockets, each 8 cores).   Each core happens to have 8 threads.    (This is on a beefy POWER8 system).    With the above blueprint,  I can now create a 1 socket, 2 core, 8 thread guest.    

  All works fine, except that I noticed "Free VCPUS:  0' even though I'm
  really only using two cores.    I'd think I would see 14 free VCPUs in
  this scenario.

  Guest lscpu output: 
  [root@bare-precise ~]# lscpu
  Architecture:          ppc64
  CPU op-mode(s):        32-bit, 64-bit
  Byte Order:            Big Endian
  CPU(s):                16
  On-line CPU(s) list:   0-15
  Thread(s) per core:    8
  Core(s) per socket:    2
  Socket(s):             1
  NUMA node(s):          1
  Model:                 IBM pSeries (emulated by qemu)
  L1d cache:             64K
  L1i cache:             32K
  NUMA node0 CPU(s):     0-15

  Resulting tracker
  2014-08-12 12:17:18.874 96650 AUDIT nova.compute.resource_tracker [-] Free VCPUS: 0

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