How to effectively restore to a snapshot?

Question

linux

We have virtual machines that need to be rolled back to snapshot N. We are currently working with qemu and doing this task using libvirt . Rollback occurs by calling the virDomainRevertToSnapshot function , this function is blocking. In our project, a situation is possible when it is necessary to roll back more than 10 virtual machines to a snapshot at the same time, the question is how to do this more efficiently without losing performance and not blocking the user input stream?

Answer 1

1) Store images in storage with the COW mechanism (ceph, ocfs2, btrfs, zfs)
2) instead of rolling back to a snapshot, simply create a new image based on the desired snapshot, and delete the old image.
The first and second together make it possible to clone machines in the hundreds per second.