For the last two weeks or so we've been working on vzstats -- a way to get some statistics about OpenVZ usage. The system consists of a server, deployed to http://stats.openvz.org/, and clients installed onto OpenVZ machines (hardware nodes). This is currently in beta testing, with 71 servers participating at the moment. If you want to participate, read http://openvz.org/vzstats and run
So far we have some interesting results. We are not sure how representative they are -- probably they aren't, much more servers are needed to participate-- but nevertheless they are interested. Let's share a few preliminary findings.
First, it looks like almost no one is using 32-bits on the host system anymore. This is reasonable and expected. Indeed, who needs system limited to 4GB of RAM nowdays?
Second, many hosts stay on latest stable RHEL6-based OpenVZ kernel. This is pretty good and above our expectations.
Third, very few run ploop-based containers. We don't understand why. Maybe we should write more about features you get from ploop, such as instant snapshots and improved live migration.
yum install vzstats on your OpenVZ boxes.So far we have some interesting results. We are not sure how representative they are -- probably they aren't, much more servers are needed to participate-- but nevertheless they are interested. Let's share a few preliminary findings.
First, it looks like almost no one is using 32-bits on the host system anymore. This is reasonable and expected. Indeed, who needs system limited to 4GB of RAM nowdays?
Second, many hosts stay on latest stable RHEL6-based OpenVZ kernel. This is pretty good and above our expectations.
Third, very few run ploop-based containers. We don't understand why. Maybe we should write more about features you get from ploop, such as instant snapshots and improved live migration.


Comments
Basically, a backup is:
- create snapshot
- copy this snapshot
- merge this snapshot down
If you don't do merge, you can have real differential backups, just by copying the next snapshot.
Also, see vzctl man page (http://wiki.openvz.org/Man/vzctl.8#Snapshotting) on available snapshot commands. In addition,
vzctl 4.3 will add snapshot-mount and snapshot-umount commands.