Dmytro,
There are two PRs we've been working on to improve Ceph snapshots. Firstly, a patch was merged last week that copies the image to secondary as a QCOW2 image, rather than raw. This obviously creates a much smaller image if the volume is sparse. Secondly, we've been working on enabling a feature that prevents copying to secondary from occurring at all. This one is a work in progress, but it looks like we've almost got most of the kinks worked out. You can look at that PR here: https://github.com/apache/cloudstack/pull/1644 - Si ________________________________ From: Dmytro Shevchenko <[email protected]> Sent: Thursday, September 29, 2016 9:47 AM To: [email protected] Subject: VM not responding on commands until snapshot running Hi, I noticed that while volume snapshot running, VM not executing other commands as Reboot or Stop. They are waiting in queue until previous command completed. Can anyone explain this behaviour, is this normal and why? I'm using Ceph as primary storage and creating snapshot takes several seconds, but as next step CS copy this snap to secondary storage via 'qemu-img convert ...' and this operation is quite slow. Tested on 4.5.1 and 4.8.0.1 versions. Ceph as primary storage and NFS as secondary. -- Best regards Dmytro
