On Mon, Jan 09, 2017 at 10:29:01AM -0800, W Kern wrote: > As is already well documented, we find that we need cache='none' to support > migration, otherwise there is the chance of a hang and/or failure to pivot. > > However we prefer the default of cache=writethrough when operating in > production. > > Our practice is to 'shutdown' the VM completely make the change with virsh > edit, then restart. Then we have to repeat the process to revert back once > we migrate. > > Is it possible to change that function on the fly and avoid the > shutdown/start process? Nope, there's no way to change the cache mode on the fly. > Note: we have had inconsistent results with virsh edit first and then a > reboot. A complete shutdown seems to be necessary, but I am hoping there is > some other procedure available. "virsh edit" will always just change the offline persistent config. This config will be used next time the guest is *cold* booted. If you just do a reboot inside the guest, this is a warm reboot, and so the QEMU process never stops running. This means we don't pick up the new offline config you wrote. Regards, Daniel -- |: http://berrange.com -o- http://www.flickr.com/photos/dberrange/ :| |: http://libvirt.org -o- http://virt-manager.org :| |: http://entangle-photo.org -o- http://search.cpan.org/~danberr/ :| _______________________________________________ libvirt-users mailing list libvirt-users@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/libvirt-users
