Red Hat Bugzilla – Bug 1460637
The amount of max vpu that retrieve from qemu hash file and domcapabilities are different.
Last modified: 2017-06-12 23:27:02 EDT
Created attachment 1287006 [details]
xml file that is related to this bug
Description of problem:
The amount of max vpu that retrieve from qemu hash file and domcapabilities are different, And this situation is occurred on ppc only.
Version-Release number of selected component (if applicable):
Red Hat Enterprise Linux Server release 7.4 Beta (Maipo)
Linux ibm-p8-garrison-02.rhts.eng.bos.redhat.com 3.10.0-675.el7.ppc64le #1 SMP Mon May 29 23:22
host cpus information are as follows.
Byte Order: Little Endian
On-line CPU(s) list: 0,8,16,24,32,40,48,56,64,72,80,88,96,104,112,120
Off-line CPU(s) list: 1-7,9-15,17-23,25-31,33-39,41-47,49-55,57-63,65-71,73-79,81-87,89-95,97-103,105-111,113-119,121-127
Thread(s) per core: 1
Core(s) per socket: 8
NUMA node(s): 2
Model: 1.0 (pvr 004c 0100)
Model name: POWER8NVL (raw), altivec supported
CPU max MHz: 4023.0000
CPU min MHz: 2061.0000
L1d cache: 64K
L1i cache: 32K
L2 cache: 512K
L3 cache: 8192K
NUMA node0 CPU(s): 0,8,16,24,32,40,48,56
NUMA node1 CPU(s): 64,72,80,88,96,104,112,120
Steps to Reproduce:
1. Get amount of max vcpu
# virsh domcapabilities
Get element about vcpu, as follows.
# tail /var/cache/libvirt/qemu/capabilities/3c76bc41d59c0c7314b1ae8e63f4f765d2cf16abaeea081b3ca1f5d8732f7bb1.xml
Get amount of maxCpus for default machine, as follows.
<machine name='pseries-rhel7.4.0' alias='pseries' hotplugCpus='yes' maxCpus='1024'/>
The vcpu values which retrieved from domcapabilities and qemu-kvm hash are different.
The max cpus total is equal whether the value come from domcapabilities or qemu-kvm hash. such as above, vcpu attribute should equal with machine attribute maxCpus.
Note: Above files that related to xml can be found on attachment.
The XML files in /var/cache/libvirt/qemu are for internal use only. Users should not touch them at all. Since you don't describe anything besides a mismatch of those I don't see a problem here. The data in domain capabilities is adapted to what is actually supported by the host.