On Thu, Mar 03, 2011 at 10:00:14PM +0800, Daniel Veillard wrote: > On Thu, Mar 03, 2011 at 11:48:51AM +0000, Daniel P. Berrange wrote: > > On Thu, Mar 03, 2011 at 06:26:19PM +0800, Daniel Veillard wrote: > > > Something like killall -USR2 libvirtd allows to see the > > > kind of output one get, an idle libvirtd is quiet, but > > > handle/timer/fdpolls tend to be very verbose, maybe we need > > > an intermediate debug level, but that would also impact the > > > API. Maybe now that this part is well debugged some of those > > > could be suppressed or commented off. > > > > > > Also the buffer is a statically allocated 64KB, maybe this > > > could be made more flexible but IMHO that's not fundamental. > > > > 64 KB is unlikely to be sufficiently large if libvirt is running > > under RHEV with moderate load. With a fairly strict log filter > > of '1:libvirt 1:util 1:qemu' RHEV generates > 300 MB of logs > > in ~10 minutes. This works out at approx 512 KB per second so > > a 64 KB buffer will only capture 125 milliseconds at that log > > filter level, and far far less if collecting full debug logs > > yeah, I was afraid of this kind of scenarios, and went for the minimal > approach since the static buffer is already in the current code. Problem > is that I don't think we should really rely on an user provided value, > and getting a dynamic algorithm (keep say at least one second worth of > log) sounds hard to implement right. I was somehow hoping that some of > the background noises could be reduced by further patches. Another > option would be to apply a specific filter (which could be empty by > default) for the debug buffer, and that is rather trivial to implement.
We could make a configurable in libvirtd.conf for buffer size. eg to set a 1 MB ringbuffer, users could do: log_ringbuffer = 1048576 Regards, Daniel -- |: http://berrange.com -o- http://www.flickr.com/photos/dberrange/ :| |: http://libvirt.org -o- http://virt-manager.org :| |: http://autobuild.org -o- http://search.cpan.org/~danberr/ :| |: http://entangle-photo.org -o- http://live.gnome.org/gtk-vnc :| -- libvir-list mailing list libvir-list@redhat.com https://www.redhat.com/mailman/listinfo/libvir-list
