RHEL Engineering is moving the tracking of its product development work on RHEL 6 through RHEL 9 to Red Hat Jira (issues.redhat.com). If you're a Red Hat customer, please continue to file support cases via the Red Hat customer portal. If you're not, please head to the "RHEL project" in Red Hat Jira and file new tickets here. Individual Bugzilla bugs in the statuses "NEW", "ASSIGNED", and "POST" are being migrated throughout September 2023. Bugs of Red Hat partners with an assigned Engineering Partner Manager (EPM) are migrated in late September as per pre-agreed dates. Bugs against components "kernel", "kernel-rt", and "kpatch" are only migrated if still in "NEW" or "ASSIGNED". If you cannot log in to RH Jira, please consult article #7032570. That failing, please send an e-mail to the RH Jira admins at rh-issues@redhat.com to troubleshoot your issue as a user management inquiry. The email creates a ServiceNow ticket with Red Hat. Individual Bugzilla bugs that are migrated will be moved to status "CLOSED", resolution "MIGRATED", and set with "MigratedToJIRA" in "Keywords". The link to the successor Jira issue will be found under "Links", have a little "two-footprint" icon next to it, and direct you to the "RHEL project" in Red Hat Jira (issue links are of type "https://issues.redhat.com/browse/RHEL-XXXX", where "X" is a digit). This same link will be available in a blue banner at the top of the page informing you that that bug has been migrated.
Bug 1170495 - ignore emulatorpin when vcpu placement is auto
Summary: ignore emulatorpin when vcpu placement is auto
Keywords:
Status: CLOSED ERRATA
Alias: None
Product: Red Hat Enterprise Linux 6
Classification: Red Hat
Component: libvirt
Version: 6.6
Hardware: x86_64
OS: Linux
medium
medium
Target Milestone: rc
: ---
Assignee: Michal Privoznik
QA Contact: Virtualization Bugs
URL:
Whiteboard:
Depends On: 1170484 1170492
Blocks:
TreeView+ depends on / blocked
 
Reported: 2014-12-04 07:17 UTC by Jincheng Miao
Modified: 2015-07-22 05:48 UTC (History)
6 users (show)

Fixed In Version: libvirt-0.10.2-49.el6
Doc Type: Bug Fix
Doc Text:
Clone Of: 1170492
Environment:
Last Closed: 2015-07-22 05:48:20 UTC
Target Upstream Version:
Embargoed:

Attachments (Terms of Use)


Links
System ID Private Priority Status Summary Last Updated
Red Hat Product Errata RHBA-2015:1252 0 normal SHIPPED_LIVE libvirt bug fix update 2015-07-20 17:50:06 UTC

Description Jincheng Miao 2014-12-04 07:17:48 UTC 
+++ This bug was initially created as a clone of Bug #1170492 +++

Description of problem:
vcpu placement is default to numatune placement or "static" if cpuset is specified.
So if user edit domain xml as:
  <vcpu placement='static' current='2'>6</vcpu>
  <numatune>
    <memory mode='strict' placement='auto'/>
  </numatune>

libvirt will turn vcpu placement to 'auto', like:
  <vcpu placement='auto' current='2'>6</vcpu>
  <numatune>
    <memory mode='strict' placement='auto'/>
  </numatune>

But this tuning will break the rule of emulatorpin is not allowed if attribute placement of element vcpu is "auto".

In other word, emulatorpin could be set when vcpu placement is 'static', and numatune memory placement is 'auto':
  <vcpu placement='auto' current='2'>6</vcpu>
  <cputune>
    <emulatorpin cpuset='1-3'/>
  </cputune>
  <numatune>
    <memory mode='strict' placement='auto'/>
  </numatune>



Version-Release number of selected component (if applicable):
libvirt-1.2.8-9.el7.x86_64
qemu-kvm-rhev-2.1.2-13.el7.x86_64

How reproducible:
100%

Steps to Reproduce:
1. edit domain xml
# virsh edit r7a
...
  <vcpu placement='static' current='2'>6</vcpu>
  <cputune>
    <emulatorpin cpuset='1-3'/>
  </cputune>
  <numatune>
    <memory mode='strict' placement='auto'/>
  </numatune>

...

# virsh dumpxml r7a
...
  <vcpu placement='auto' current='2'>6</vcpu>
  <cputune>
    <emulatorpin cpuset='1-3'/>
  </cputune>
  <numatune>
    <memory mode='strict' placement='auto'/>
  </numatune>
...

2. start guest
# virsh start r7a

3. check via emulatorpin
# virsh emulatorpin r7a
emulator: CPU Affinity
----------------------------------
       *: 1-3

4. check via cgroup
# cat /sys/fs/cgroup/cpuset/machine.slice/machine-qemu\\x2dr7a.scope/emulator/cpuset.cpus
0-7


Expect result:
Either report error for specifying emulatorpin when vcpu placement is auto,
or ignoring emulatorpin configuration.

--- Additional comment from Jincheng Miao on 2014-12-04 02:06:05 EST ---

This problem is also existing for iothreadpin of cputune.

And It's also existed in RHEL6, I will clone it to RHEL6.

In RHEL6 libvirt-0.10.2-46.el6.x86_64:
# virsh edit r6
...
  <vcpu placement='static' current='2'>4</vcpu>
  <cputune>
    <emulatorpin cpuset='1-3'/>
  </cputune>
  <numatune>
    <memory mode='strict' placement='auto'/>
  </numatune>
...

# virsh emulatorpin r6
emulator: CPU Affinity
----------------------------------
       *: 1-3

# cat /cgroup/cpuset/libvirt/qemu/r6/emulator/cpuset.cpus 0-7
Comment 1 Michal Privoznik 2015-02-05 11:57:02 UTC 
Moving to POST:

http://post-office.corp.redhat.com/archives/rhvirt-patches/2015-February/msg00087.html
Comment 3 Jincheng Miao 2015-02-27 06:43:40 UTC 
This problem could be reproduced in libvirt-0.10.2-48.el6.x86_64:

1. define a guest with static vcpu placement and auto memory placement, and with emulatorpin
# virsh edit rhel
  <vcpu placement='static' current='2'>5</vcpu>
  <cputune>
    <emulatorpin cpuset='1-3'/>
  </cputune>
  <numatune>
    <memory mode='strict' placement='auto'/>
  </numatune>

2. then domain xml transfers into auto vcpu placement
# virsh dumpxml rhel
  <vcpu placement='auto' current='2'>5</vcpu>
  <cputune>
    <emulatorpin cpuset='1-3'/>
  </cputune>
  <numatune>
    <memory mode='strict' placement='auto'/>
  </numatune>


But in latest libvirt-0.10.2-49.el6.x86_64:
1. 
# virsh edit rhel
  <vcpu placement='static' current='2'>5</vcpu>
  <cputune>
    <emulatorpin cpuset='1-3'/>
  </cputune>
  <numatune>
    <memory mode='strict' placement='auto'/>
  </numatune>

2. 
# virsh dumpxml rhel
  <vcpu placement='static' current='2'>5</vcpu>
  <cputune>
    <emulatorpin cpuset='1-3'/>
  </cputune>
  <numatune>
    <memory mode='strict' placement='auto'/>
  </numatune>

3. check emulatorpinning
# virsh emulatorpin rhelemulator: CPU Affinity
----------------------------------
       *: 1-3


# cat /cgroup/cpuset/libvirt/qemu/rhel/emulator/cpuset.cpus 
1-3

So this problem is fixed, and I will change the status to VERIFIED.
Comment 6 errata-xmlrpc 2015-07-22 05:48:20 UTC 
Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://rhn.redhat.com/errata/RHBA-2015-1252.html
Note You need to log in before you can comment on or make changes to this bug.