Starting various VM via libvirt-bin, crashes libvirtd

[Thomas Schweikle]

Assume a kvm-qemu-server with various VM installed. Now start these virtual machines using virsh. After some VM started (about 14) libvirtd vanishes from the process list. Some further investigation gave it had crashed. I could reliably try it again and again. After starting 17 guests libvirtd crashed.
It is possible to restart libvirtd. It will run as if it never ad crashed.

ProblemType: Bug
DistroRelease: Ubuntu 11.10
Package: libvirt-bin 0.9.2-4ubuntu15.1
Uname: Linux 3.1.8 x86_64
ApportVersion: 1.23-0ubuntu4
Architecture: amd64
Date: Fri Jan 13 17:29:12 2012
InstallationMedia: Xubuntu 11.10 "Oneiric Ocelot" - Release amd64 (20111012)
ProcEnviron:
 PATH=(custom, user)
 LANG=de_DE.UTF-8
 SHELL=/bin/bash
SourcePackage: libvirt
UpgradeStatus: No upgrade log present (probably fresh install)

[Serge Hallyn (serge-hallyn)]

Thanks for taking the time to submit this bug.

Is it possible for you to run

   apport-collect 916095

on the host, after such a crash has happened (and before reboot or restarting libvirt-bin)?

Do you see any messages in syslog about OOM?

[Thomas Schweikle (tps)]

I moved to a newer version, 0.9.8 (and 0.9.9), of libvirtd and tools.
The crashes are gone with this version. On an other server (debian testing) this libvirtd-version is installed by default. Far less problems than with libvirtd 0.9.2!

[Thomas Schweikle (tps)]

# Is it possible for you to run
#
# apport-collect 916095
#
# on the host, after such a crash has happened (and before reboot or restarting libvirt-bin)?
Did not have an additional crash since I've upgraded to the latest version available from the libvirt site.

# Do you see any messages in syslog about OOM?
No, I do not see any errors related to OOM. I had a look at this again in the old logs. But the only thing logged was an exception generated by libvirtd by a null pointer dereference.

[Thomas Schweikle (tps)]

After longer investigations, this error was a known bug related to memory management. Under certain circumstances, if memory was growing short, libvirtd tried to allocate more memory, but didn't react on errors if there wasn't enough, trying to dereference the null pointer given back in such cases. This error was fixed in one of the newer versions.

[Thomas Schweikle (tps)]

In my case: starting the seventeenth VM lead, reliably, to the crash.

[Serge Hallyn (serge-hallyn)]

Thanks. I wonder if a backport of the precise libvirt (perhaps in the ubuntu-virt ppa or in backports) is the way to go, as the oneiric version just seems to be unreliable under load in several ways.

[Rolf Leggewie (r0lf)]

oneiric has seen the end of its life and is no longer receiving any updates. Marking the oneiric task for this ticket as "Won't Fix".