Bug 1279431 - enable vdsm taskset pinning by default
Summary: enable vdsm taskset pinning by default
Keywords:
Status: CLOSED CURRENTRELEASE
Alias: None
Product: vdsm
Classification: oVirt
Component: General
Version: 4.17.11
Hardware: Unspecified
OS: Unspecified
high
high
Target Milestone: ovirt-3.6.2
: 4.17.14
Assignee: Francesco Romani
QA Contact: Lukas Svaty
URL:
Whiteboard:
Depends On:
Blocks: 1247075
TreeView+ depends on / blocked
 
Reported: 2015-11-09 13:00 UTC by Michal Skrivanek
Modified: 2019-04-28 09:49 UTC (History)
6 users (show)

Fixed In Version:
Doc Type: Bug Fix
Doc Text:
Vdsm cpu pinning is now enabled by default. Vdsm uses the second available CPU in the system, to reduce the traffic on the first one which is often used as default one by other system tasks.
Clone Of:
Environment:
Last Closed: 2016-02-18 11:21:47 UTC
oVirt Team: Virt
Embargoed:
michal.skrivanek: ovirt-3.6.z?
michal.skrivanek: planning_ack?
michal.skrivanek: devel_ack+
rule-engine: testing_ack+

Attachments (Terms of Use)


Links
System ID Private Priority Status Summary Last Updated
Red Hat Bugzilla 1286462 0 urgent CLOSED Vdsm daemon failed to start, because incorrect cpu affinity 2021-02-22 00:41:40 UTC
Red Hat Knowledge Base (Solution) 2116711 0 None None None 2016-01-27 18:06:40 UTC
oVirt gerrit 48296 0 master MERGED daemon: enable cpu affinity by default 2020-11-17 03:59:36 UTC
oVirt gerrit 48619 0 master MERGED daemon: ignore cpu affinity on single processor 2020-11-17 03:59:57 UTC
oVirt gerrit 48786 0 ovirt-3.6 MERGED lib: taskset: commands should run on all cpus 2020-11-17 03:59:36 UTC
oVirt gerrit 48787 0 ovirt-3.6 MERGED daemon: enable cpu affinity by default 2020-11-17 03:59:36 UTC
oVirt gerrit 48961 0 ovirt-3.6 MERGED daemon: ignore cpu affinity on single processor 2020-11-17 03:59:36 UTC
oVirt gerrit 49402 0 master MERGED lib: daemon: autodetect online cpus for affinity 2020-11-17 03:59:35 UTC
oVirt gerrit 49562 0 master MERGED daemon: keep running without affinity. 2020-11-17 03:59:59 UTC
oVirt gerrit 49612 0 ovirt-3.6 MERGED lib: daemon: autodetect online cpus for affinity 2020-11-17 03:59:38 UTC
oVirt gerrit 49613 0 ovirt-3.6 MERGED daemon: reformat __set_cpu_affinity 2020-11-17 03:59:38 UTC
oVirt gerrit 49614 0 ovirt-3.6 MERGED daemon: keep running without affinity. 2020-11-17 03:59:37 UTC

Internal Links: 1286462

Description Michal Skrivanek 2015-11-09 13:00:52 UTC 
In bug 1247075 we introduced a new cpu_affinity option to pin vdsm threads to a limited number of physical cores to solve a GIL contention on thread scheduling

Testing didn't show any adverse effects, only benefits (improvement is proportional to the size of the host and number of VMs it's running)

Let's enable it by default
Comment 1 Dan Kenigsberg 2015-11-11 09:33:21 UTC 
using 'taskset 0' pins Vdsm to the first CPU, which is usually a bit more busy than others. Using 'taskset 1' assume that the host has at least two CPUs. That's true in every real-life scenario. Gil, is it also correct on all QE setups, where virtual hosts are sometime used?
Comment 2 Francesco Romani 2015-11-18 17:01:34 UTC 
Please note that http://gerrit.ovirt.org/48619 should take care of this uncommon -but important- cases.
Comment 3 Francesco Romani 2015-11-23 11:40:16 UTC 
now really MODIFIED, all patches merged on branch 3.6
Comment 4 Sandro Bonazzola 2015-11-24 16:43:43 UTC 
Please set target release or I can't move the bug to ON_QA automatically.
Comment 5 Red Hat Bugzilla Rules Engine 2015-11-24 18:09:06 UTC 
Bug tickets that are moved to testing must have target release set to make sure tester knows what to test. Please set the correct target release before moving to ON_QA.
Comment 6 Nir Soffer 2015-11-30 19:30:20 UTC 
Should move this to next build.
Comment 7 Michal Skrivanek 2015-12-01 07:16:05 UTC 
patch reverted in build 23 onwards, solution moved to 3.6.2
Comment 8 Gil Klein 2016-01-27 10:33:54 UTC 
# rpm -qi vdsm
Name        : vdsm
Version     : 4.17.18
Release     : 0.el7ev
Architecture: noarch
Install Date: Wed 20 Jan 2016 06:30:30 PM UTC
Group       : Applications/System
Size        : 3802272
License     : GPLv2+
Signature   : RSA/SHA256, Wed 20 Jan 2016 05:31:13 PM UTC, Key ID 938a80caf21541eb
Source RPM  : vdsm-4.17.18-0.el7ev.src.rpm
Build Date  : Tue 19 Jan 2016 12:34:08 PM UTC
Build Host  : x86-017.build.eng.bos.redhat.com
Relocations : (not relocatable)
Packager    : Red Hat, Inc. <http://bugzilla.redhat.com/bugzilla>
Vendor      : Red Hat, Inc.
URL         : http://www.ovirt.org/wiki/Vdsm
Summary     : Virtual Desktop Server Manager

# grep affinity /var/log/vdsm/vdsm.log 
MainThread::INFO::2016-01-27 09:47:12,758::vdsm::282::vds::(__set_cpu_affinity) VDSM will run with cpu affinity: frozenset([1])
Note You need to log in before you can comment on or make changes to this bug.