Bug 702775

Summary:	Constant load on F15 machine with no processes using CPU
Product:	[Fedora] Fedora	Reporter:	Jeff Sheltren <sheltren>
Component:	kernel	Assignee:	Kernel Maintainer List <kernel-maint>
Status:	CLOSED DUPLICATE	QA Contact:	Fedora Extras Quality Assurance <extras-qa>
Severity:	unspecified	Docs Contact:
Priority:	unspecified
Version:	15	CC:	gansalmon, itamar, jonathan, kernel-maint, madhu.chinakonda
Target Milestone:	---
Target Release:	---
Hardware:	x86_64
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	Bug Fix
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2011-05-18 18:09:41 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:

Description Jeff Sheltren 2011-05-07 02:45:18 UTC

System has a constant load of ~1.00 with no intensive processes running.  This has been a consistent issue on this machine since the F15 alpha.  Currently running kernel version 2.6.38.5-22.fc15.x86_64.

top shows no process using much CPU, nor any notable I/O wait.

This is immediate after boot and load never goes down.

Tried checking if this was perhaps some process running on and off fast enough that it wasn't visible in top.  Running ps repeatedly didn't reveal any process, and the pids of the ps processes incremented in sequence demonstrating there were no other processes starting and stopping between ps runs.

Hardware is a Lenovo Thinkpad with an Intel i7 CPU.

Comment 1 Jeff Sheltren 2011-05-14 20:26:31 UTC

Did a fresh install of F15 and latest updates-testing packages on the same hardware and after the first reboot this problem persists.

2.6.38.5-24.fc15.x86_64

Comment 2 Jeff Sheltren 2011-05-16 14:49:15 UTC

Idle load issue persists with latest 2.6.38.6-26.rc1.fc15.x86_64 kernel, even when booted into single user mode.

Comment 3 Jeff Sheltren 2011-05-16 20:23:59 UTC

perf top shows 'drm_addmap_core' hovering around 20-30% of samples.  Is that meaningful?

Comment 4 Chuck Ebbert 2011-05-17 13:25:33 UTC

It's probably just a process stuck in uninterruptible sleep. The ps command should be able to show that. If it's not causing CPU load then it's not really harmful though.

Comment 5 Jeff Sheltren 2011-05-17 15:52:03 UTC

(In reply to comment #4)
> It's probably just a process stuck in uninterruptible sleep. The ps command
> should be able to show that. If it's not causing CPU load then it's not really
> harmful though.

ps ax shows:
 627 ?        D      0:00 [ips-monitor]

As the only process in that state.

Comment 6 Chuck Ebbert 2011-05-18 18:09:41 UTC


*** This bug has been marked as a duplicate of bug 703511 ***

Comment 7 Jeff Sheltren 2011-05-18 18:55:28 UTC

(In reply to comment #6)
> 
> *** This bug has been marked as a duplicate of bug 703511 ***

Chuck, thanks for your help on this!