search for: virhashiterationerror

Hey! On many of our servers, we often have the following error: error : virHashForEach:597 : Hash operation not allowed during iteration When querying the list of domains, this means libvirt will silently return 0 domain (most uses of virHashForEach don't handle the return code). We are using a hook, but the hook doesn't query libvirt back, so it should be safe from this point of view.

❦ 4 avril 2018 11:17 +0200, Michal Privoznik <mprivozn@redhat.com> : > Dunno, this is the first time I hear about this issue. Maybe you can try > to set a break point on virHashIterationError() and when it's hit get > stacktrace of all threads 't a a bt'. That might shed more light into > the issue. Smells like we are not locking somewhere properly. So, we have two threads iterating. Both of them originates from virNetServerProgramDispatchCall. So, it seems there is a...

...of it (e.g. some in-house patches)? > > Is it an expected constraint to not be able to reliably query libvirt > from several sources? Have fixes for this problem been pushed since 3.6? > Dunno, this is the first time I hear about this issue. Maybe you can try to set a break point on virHashIterationError() and when it's hit get stacktrace of all threads 't a a bt'. That might shed more light into the issue. Smells like we are not locking somewhere properly. Also, you might want to try the latest release of 4.2.0 and see if the bug still reproduces. Michal

On 04/04/2018 02:59 PM, Vincent Bernat wrote: > ❦ 4 avril 2018 11:17 +0200, Michal Privoznik <mprivozn@redhat.com> : > >> Dunno, this is the first time I hear about this issue. Maybe you can try >> to set a break point on virHashIterationError() and when it's hit get >> stacktrace of all threads 't a a bt'. That might shed more light into >> the issue. Smells like we are not locking somewhere properly. > > So, we have two threads iterating. Both of them originates from > virNetServerProgramDispatchCall....