Bug 1044111

Summary:	[GSS 7.0][RFE] tuned should edit kernel command line
Product:	Red Hat Enterprise Linux 7	Reporter:	Karl Hastings <kasmith>
Component:	tuned	Assignee:	Jaroslav Škarvada <jskarvad>
Status:	CLOSED ERRATA	QA Contact:	qe-baseos-daemons
Severity:	low	Docs Contact:
Priority:	low
Version:	7.0	CC:	jeder, jscotka, jskarvad, mgrepl, vgaikwad, yruseva
Target Milestone:	rc	Keywords:	FutureFeature
Target Release:	---
Hardware:	All
OS:	Linux
URL:	http//
Whiteboard:
Fixed In Version:	tuned-2.4.0-0.el7	Doc Type:	Enhancement
Doc Text:	Feature: Tuned can now edit kernel (dracut) boot command line. Reason: See comment 3. Result: For full description of this feature see comment 8.	Story Points:	---
Clone Of:
Clones:	1130818 1132234 1135974 (view as bug list)		Environment:
Last Closed:	2015-03-05 13:28:41 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:
Bug Depends On:
Bug Blocks:	1064025, 1110708, 1113520, 1130818, 1132234, 1135974, 1191595

Description Karl Hastings 2013-12-17 20:09:27 UTC

Description of problem:
tuned should have the ability to add options to the kernel command line based on the defined profiles

Steps to Reproduce:
1. Given a tuned profile that requests a kernel command line parameter
  e.g. intel_idle.max_cstate=0

Expected results:
tuned should (using grubby or something similar) be able to edit the kernel command line to add/remove the specified kernel option.

Comment 2 Jaroslav Škarvada 2014-07-10 12:00:49 UTC

Currently tuned allows changing the settings in the run time without reboot and this RFE will break this useful feature.

Tuned now controls the max_cstate dynamically through the PM QOS interface which is very flexible. What will be the benefit to set it statically? In such case tuned will not be able to increase the max_cstate without reboot. This may also confuse users.

Please note with grub2, editing the kernel command line is a pain. You need to patch the grub.cfg and also simultaneously edit the grub2 templates because you need to cover the case when the user regenerates the config with the grub2-mkconfig command. AFAIK this is currently not done by grubby.

Is there any other use case than the intel_idle.max_cstate=0? Is it needed for custom profiles? In such case I could write such plugin, but I am against using this feature in the shipped profiles.

Comment 4 Karl Hastings 2014-07-10 23:14:56 UTC

Jaroslav,

As Jeremy has mentioned there are quite a few other parameters that would be nice if tuned could handle from a profile.

the intel_idel.max_cstate=0 was simply an example.

Comment 7 Jaroslav Škarvada 2014-09-29 14:38:11 UTC

Upstream commit adding this feature:
https://git.fedorahosted.org/cgit/tuned.git/commit/?id=5b8a2d2e8e77ca502ed70da6db86ffe9eaae5076

Comment 17 Jiri Herrmann 2014-12-12 15:31:22 UTC

If this Feature should be included in the 7.1 Release Notes, could you please change the Doc Type from Enhancement to "Release Note"?

Note that the Release Notes are intended to list the most prominent and customer-relevant new features rather than every single enhancement.

Cheers,
Jirka

Comment 18 Jaroslav Škarvada 2014-12-12 16:17:45 UTC

(In reply to Jiri Herrmann from comment #17)
I think it doesn't need release note.

Comment 21 errata-xmlrpc 2015-03-05 13:28:41 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.

https://rhn.redhat.com/errata/RHBA-2015-0550.html