Not really. If it's 4:00:00 and the system clock says 4:20:00, and then it exits... then 21 minutes goes by and the system clock is set correctly. It is indistinguishable from the clock not stepping and 1 minute going by.

> (and of course, don’t futz with system time while memcached isn’t running).

Well, yes, that's what the original thing you quoted said: "Your system clock must be set correctly, or at least it must not move before memcached has restarted."