Note: This bug is displayed in read-only format because the product is no longer active in Red Hat Bugzilla.

Bug 865347

Summary:	RFE: Hypervisor installer should change host's IO scheduler to deadline for improved performance
Product:	Red Hat OpenStack	Reporter:	Yaniv Kaul <ykaul>
Component:	openstack-packstack	Assignee:	Martin Magr <mmagr>
Status:	CLOSED ERRATA	QA Contact:	Nir Magnezi <nmagnezi>
Severity:	high	Docs Contact:
Priority:	high
Version:	1.0 (Essex)	CC:	aortega, apevec, bloch, derekh, jkt, markmc, mwagner, ykaul
Target Milestone:	snapshot4	Keywords:	Improvement, Triaged
Target Release:	2.1
Hardware:	Unspecified
OS:	Unspecified
Whiteboard:
Fixed In Version:	openstack-packstack-2012.2.3-0.1.dev454	Doc Type:	Enhancement
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2013-03-21 18:22:41 UTC	Type:	Bug
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:

Description Yaniv Kaul 2012-10-11 09:31:40 UTC

Description of problem:
The IO performance of VMs when running on a host with the IO scheduler set as deadline is better than when running with the default scheduler (CFQ). The os-installer should change the IO scheduler.

Just add elevator=deadline to the kernel args.

Version-Release number of selected component (if applicable):


How reproducible:


Steps to Reproduce:
1.
2.
3.
  
Actual results:


Expected results:


Additional info:

Comment 2 Perry Myers 2013-01-10 16:25:38 UTC

Perf team used to have a tool called tuna that made it possible to apply profiles to hosts, and one of the profiles was for a 'kvm host'

@mwagner, can you assist with info here?

Comment 3 Yaniv Kaul 2013-01-10 16:35:32 UTC

(In reply to comment #2)
> Perf team used to have a tool called tuna that made it possible to apply
> profiles to hosts, and one of the profiles was for a 'kvm host'
> 
> @mwagner, can you assist with info here?

I thought Packstack was going to use otopi/ovirt-host-deploy.
It's available there:
http://gerrit.ovirt.org/gitweb?p=ovirt-host-deploy.git;a=blob;f=src/plugins/ovirt-host-deploy/tune/iosched.py;hb=HEAD

Comment 4 Mark Wagner 2013-01-10 19:52:08 UTC

Hi, tuned is a user space package that controls the profiles. There are profiles for virtual-host and virtual-guest amongst others. It should be possible to install and configure the  use of the virtual-host profile. 

Note that tuna is a different tool.

Comment 5 Derek Higgins 2013-01-23 08:09:39 UTC

I have to translate this into a equivalent puppet manifest but would something like this be appropriate ?

if ! tuned-adm active | grep virtual-host 2> /dev/null ; then
    tuned-adm profile virtual-host
fi

This probably changes more then just the IO scheduler but its all good stuff right?

Also does this changed persist on reboot?

thanks,
Derek.

Comment 6 Derek Higgins 2013-02-21 13:17:04 UTC

Fix submitted upstream
https://review.openstack.org/#/c/22540/

Comment 8 Nir Magnezi 2013-03-13 12:20:09 UTC

Verified NVR: openstack-packstack-2012.2.3-0.1.dev454.el6ost.noarch

1. Verified that 'tuned-adm active | grep virtual-host' returned no output.
2. Used packstack to install openstack.
3. Verified Active Profile again:

# tuned-adm active | grep virtual-host
Current active profile: virtual-host

Comment 11 errata-xmlrpc 2013-03-21 18:22:41 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.

http://rhn.redhat.com/errata/RHSA-2013-0671.html