Bug 709049

Summary:	cpuspeed should reset to max frequency when "service cpuspeed stop" is issued
Product:	Red Hat Enterprise Linux 6	Reporter:	Petr Šabata <psabata>
Component:	cpuspeed	Assignee:	Petr Šabata <psabata>
Status:	CLOSED WONTFIX	QA Contact:	Qian Cai <qcai>
Severity:	low	Docs Contact:
Priority:	low
Version:	6.0	CC:	qcai, syeghiay, yossig
Target Milestone:	rc
Target Release:	---
Hardware:	Unspecified
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	Bug Fix
Doc Text:		Story Points:	---
Clone Of:	707989	Environment:
Last Closed:	2013-08-12 14:43:33 UTC	Type:	---
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Bug Depends On:	707989
Bug Blocks:	836169

Description Petr Šabata 2011-05-30 13:22:19 UTC

+++ This bug was initially created as a clone of Bug #707989 +++

Description of problem:


If cpuspeed was enabled on a system and the user issues "service cpuspeed stop"  followed by "chkconfig cpuspeed off",  the cpu frequency of the cpus is left at the current frequency that was set by the kernel.

So if the speed was reduced by the kernel to a lower rate, it is not reset to the maximum rate.

I think the common user may miss this and get poor performance of his system until he reboots his system.

There is an easy way to work around this but i suggest that this behavior should be changed.



Version-Release number of selected component (if applicable):
cpuspeed-1.2.1-9.el5 and earlier

How reproducible:
enable cpuspeed cause it to reduce cpu frequency and then issue stop cpuspeed.
CPU frequency stays as is.

I am not sure I can call it a bug, maybe more a change to reduce the risk of a user to stay with a system working unexpectedly slow. 

Thank you!

--- Additional comment from psabata on 2011-05-26 16:14:01 CEST ---

Thanks for the report.

Indeed, switching to the highest frequency available in scaling_available_frequencies would be probably the best idea.

Comment 2 RHEL Program Management 2011-07-06 00:15:56 UTC

This request was evaluated by Red Hat Product Management for
inclusion in the current release of Red Hat Enterprise Linux.
Because the affected component is not scheduled to be updated
in the current release, Red Hat is unfortunately unable to
address this request at this time. Red Hat invites you to
ask your support representative to propose this request, if
appropriate and relevant, in the next release of Red Hat
Enterprise Linux. If you would like it considered as an
exception in the current release, please ask your support
representative.

Comment 4 RHEL Program Management 2012-07-10 05:53:05 UTC

This request was not resolved in time for the current release.
Red Hat invites you to ask your support representative to
propose this request, if still desired, for consideration in
the next release of Red Hat Enterprise Linux.

Comment 5 RHEL Program Management 2012-07-10 23:10:24 UTC

This request was erroneously removed from consideration in Red Hat Enterprise Linux 6.4, which is currently under development.  This request will be evaluated for inclusion in Red Hat Enterprise Linux 6.4.

Comment 12 Petr Šabata 2013-08-12 14:43:33 UTC

I'm going to close this as a WONTFIX.

The highest available frequency isn't necessarily the state we were in before we started the cpuspeed service and setting that might even be a) dangerous on some systems, b) impossible in case the limits have been altered externally and the kernel isn't aware of that.  Because of the latter, I don't think remembering the state in the moment of our start would be beneficial either.

We could possibly introduce new configuration settings for what frequency and governor we should switch to upon exiting but I don't find this too useful.