In the "Gotchas" section of the BTRFS wiki it's mentioned that performance issues could occur with highly fragmented files (vm images and databases). The solution for this is to disable copy-on-write for those files.
For a Debian installation, in what system directories should we also disable copy-on-write (mounting them in a
To reduce the broadness of the question, assume it's a server with full allocation image VMs (log server, file server, for example). Also, operations like
btrfs add/remove missing causes a lot of logging to occur in the host machine.
My question is, besides disabling copy-on-write for those "write active" VMs, is disabling it on the
/var/log directory enough or are there other system directories/files that I could also do this from the start (like all of
/tmp as Stephen Harris suggested)? Or is it just a matter of starting somewhere, checking regularly for fragmented files and performance issues, and disabling the copy-on-write when needed?