Bug 618720

Summary:	qemu-kvm hangs for about 1 min at start up
Product:	[Fedora] Fedora	Reporter:	Richard W.M. Jones <rjones>
Component:	qemu	Assignee:	Fedora Virtualization Maintainers <virt-maint>
Status:	CLOSED DUPLICATE	QA Contact:	Fedora Extras Quality Assurance <extras-qa>
Severity:	medium	Docs Contact:
Priority:	low
Version:	rawhide	CC:	amit.shah, berrange, clalance, crobinso, dwmw2, ehabkost, extras-orphan, itamar, jaswinder, jforbes, knoel, notting, ondrejj, quintela, scottt.tw, tburke, virt-maint
Target Milestone:	---
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	Bug Fix
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2012-07-10 12:14:04 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 Richard W.M. Jones 2010-07-27 15:23:30 UTC

Description of problem:

Since upgrading the kernel to the latest from Rawhide, qemu-kvm
suddenly hangs for about a minute when it starts up (before apparently
running any part of the guest OS).

The easiest way to see this is to run

  $ libguestfs-test-tool

and observe a very long hang after the command line is printed, and
before the guest appliance boots (at normal speed).

During this time, qemu-kvm consumes 100%, ie. all 4 CPUs.

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

kernel 2.6.35-0.56.rc6.git1
qemu-kvm-0.12.3-7.fc14.x86_64

How reproducible:

Always.

Steps to Reproduce:
1. time guestfish -a /dev/null run
2.
3.
  
Actual results:

Takes about 1m24.

Expected results:

0m08s.

Additional info:

Comment 1 Bug Zapper 2010-07-30 12:53:48 UTC

This bug appears to have been reported against 'rawhide' during the Fedora 14 development cycle.
Changing version to '14'.

More information and reason for this action is here:
http://fedoraproject.org/wiki/BugZappers/HouseKeeping

Comment 2 Richard W.M. Jones 2010-08-03 11:06:20 UTC

Switching back to Rawhide.  Still present in latest kernel-2.6.35-0.57.rc6.git5.fc15.

The issue is fixes itself if I go back to the 2.6.34 kernel.

I also tried upstream qemu compiled from git => same thing.

I also tried stracing qemu and qemu-kvm, but there's nothing that I
can tell that is interesting going on.  Just in a loop doing select and
occasional reads/writes to file descriptors.

Comment 3 Richard W.M. Jones 2010-08-03 14:35:04 UTC

The root cause is possibly:
http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commitdiff;h=7972995b0c346de76

See discussion here:
http://lists.gnu.org/archive/html/qemu-devel/2010-08/threads.html#00133

Comment 4 Fedora Admin XMLRPC Client 2012-03-15 17:58:36 UTC

This package has changed ownership in the Fedora Package Database.  Reassigning to the new owner of this component.

Comment 5 Cole Robinson 2012-07-10 12:14:04 UTC

Pretty sure this has long since been improved, so closing

Comment 6 Cole Robinson 2012-07-10 13:24:06 UTC


*** This bug has been marked as a duplicate of bug 730128 ***