Is it safe to put <configdirectory>/proc and <configdirectory>/lock on a tmpfs filesystem?
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It’s safe to put both of these in tmpfs, and since they’re fairly busy
it’s a good idea for performance reasons. Further, nothing ever
removes files from <configdirectory>/lock/, so it’s probably a good
idea in general to mount that on tmpfs such that a reboot will purge
it. The Cyrus code will create all the necessary directory structure
under <configdirectory>/lock on-demand.
