Well for now just consider the DB usage as another useI don't have any public data available for this DB usage,Sorry, that doesn't explain anything.
of profiling. But one can easily draw scenarios where
a monotonic timestamp is also used to guarantee transaction
Yes and no. Monotonicity is a poor substitute for a moreSearch for "flight recorder". This feature is intended toFor profiling work fast timestamping is of course great, but surely
be enabled all the time, but with non-vsyscall gettimeofday
the performance impact is unacceptably high, so they are using
there is no monotonicity requirement?
generic mechanism that might provide an indication that a
discontinuity has occurred (forward or backward); if an app
could get both the timestamp AND some kind of "continuity
generation counter" (basically a much more sophisticated
form of TSC_AUX that changes whenever the timestamp is
coming from a different source), perhaps all problems could be solved.
I don't think we'll be able to provide monotonicity with vsyscall onTrue, though clock_gettime(CLOCK_MONOTONIC) can provide
tsc-broken hosts, so we'll be limited to correcting the tsc frequency
after migration for good-tsc hosts.
the monotonicity where it is required.