[Date Prev][Date Next]   [Thread Prev][Thread Next]   [Thread Index] [Date Index] [Author Index]

[libvirt] libvirt(-java): How to make vm.getDomain().getJobInfo() thread safe?



Hi,

this is kind of a follow-up to an older question/discussion:
https://www.redhat.com/archives/libvir-list/2010-July/msg00267.html

As a result of that, I use a second thread for monitoring the live migration, taking actions (setting maxdowntime to a value that fits the situation) if necessary.

Although I call getJobInfo() with a quite low frequency (once a second), problems are occuring frequently, like every 10th or 15th live migration. Problems range from exceptions that the domain is not running anymore to complete JVM crashes -> http://pastebin.com/jT6sXubu Recovery from exceptions doesn't seem to work perfectly, as they seem to trigger that connections to a host can't be shut down properly because there are still open references.

Of course, in my monitoring thread I'm checking in every monitoring iteration if the domain object is not null, is still active, if the jobInfo is available yet etc. But, as I can not synchronize with vm.migrate(), there still a reasonable chance that migrate() just invalidates the current domain while I'm accessing it, no matter what I do.

Do I miss something or is that correct? Any ideas how to reliably solve it? Is there some experience from virt-manager, where (in my quite old version) I assume at least the domain is read for cpu etc. stats while live migrating...


regards,
thomas


[Date Prev][Date Next]   [Thread Prev][Thread Next]   [Thread Index] [Date Index] [Author Index]