Bug 463836

Summary:	[LTC 6.0 FEAT] 201195:Scaled utilisation metrics for power-managed systems
Product:	Red Hat Enterprise Linux 6	Reporter:	IBM Bug Proxy <bugproxy>
Component:	kernel	Assignee:	James Takahashi (IBM) <nobody+PNT0273897>
Status:	CLOSED CURRENTRELEASE	QA Contact:	Martin Jenner <mjenner>
Severity:	medium	Docs Contact:
Priority:	medium
Version:	6.0	CC:	ejratl, jlarrew, mtosatti, notting, pbog, peterm
Target Milestone:	alpha	Keywords:	FutureFeature
Target Release:	---
Hardware:	All
OS:	All
Whiteboard:
Fixed In Version:		Doc Type:	Enhancement
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2009-09-17 21:21:57 UTC	Type:	---
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:	356741, 525727

Description IBM Bug Proxy 2008-09-24 20:40:49 UTC

=Comment: #0=================================================
Emily J. Ratliff <emilyr.com> - 2008-09-24 13:52 EDT
1. Feature Overview:
Feature Id:	[201195]
a. Name of Feature:	Scaled utilization metrics for power-managed systems
b. Feature Description
Provide correct utilization metrics as a function of total CPU capacity.  For example utilization
may be relative to highest nominal state or to current power cap.  This may also impact a number of
system utilities (eg: ps, top, others...).  Currently CPU frequency scaling for power management may
cause CPU utilization metrics to become incorrect.

2. Feature Details:
Sponsor:	LTC
Architectures:
x86
x86_64
ppc64

Arch Specificity: Both
Affects Core Kernel: Yes
Delivery Mechanism: Direct from community
Category:	Kernel
Request Type:	Kernel - Enhancement from IBM
d. Upstream Acceptance:	Accepted
Sponsor Priority	2
f. Severity: Medium
IBM Confidential:	no
Code Contribution:	IBM code
g. Component Version Target:	2.6.25

3. Business Case
Sophisticated enterprise-level system and cluster management products need accurate accounting to
correctly manage CPU resource utilization versus power utilization.  Increasingly the enterprise
market is interested in mitigating and managing power consumption in servers, where interest
previously was mostly in a mobile market.  An enterprise Linux distribution which enables
sophisticated monitoring and control applications will have an advantage in this emerging market.

4. Primary contact at Red Hat: 
John Jarvis
jjarvis

5. Primary contacts at Partner:
Project Management Contact:
Sarah Wright, sarahw.com, 503-578-5145

Technical contact(s):
Dipankar Sarma, dipankar.sarma.com
Gautham R Shenoy, gautshen.com

IBM Manager:
Jeffrey Heroux, heroux.com

Comment 1 Bill Nottingham 2008-09-24 20:49:53 UTC

What configuration options, if any, are needed for this? How is it exposed to userspace for apps to use?

Comment 2 IBM Bug Proxy 2009-03-05 17:50:45 UTC

(In reply to comment #4)
> What configuration options, if any, are needed for this? How is it exposed to userspace for apps to use?

CONFIG_VIRT_CPU_ACCOUNTING=y once the chargeback accounting patches show up in mainline.  The taskstats netlink interface is how one gets advanced utime/stime data; see getdelays.c for a simple example of how it works.  The utime/stime numbers will be scaled down (or up) based on the p-state when the processor is in C0.

Comment 3 Jesse Larrew 2009-06-29 22:42:54 UTC

Assigning this to Peter Bogdanovic at IBM.

Comment 4 Peter Bogdanovic 2009-09-17 21:21:57 UTC

Support for Power processors upstream in 2.6.31.  Support of Intel and AMD processors unlikely in RHEL6.0 because the cpus don't support it properly.

Comment 5 IBM Bug Proxy 2009-11-18 13:10:30 UTC

Reassigning to Darrick, please answer Red Hat's question and move bug to Submitted state afterwards.

Since in RH cvs tree, moving to Accepted state