Hi,
On 2023-01-13 15:25:16 -0500, Tom Lane wrote:
> Andres Freund <andres@anarazel.de> writes:
> > Does anybody see a reason to not move forward with this aspect? We do a fair
> > amount of INSTR_TIME_ACCUM_DIFF() etc, and that gets a good bit cheaper by
> > just using nanoseconds.
>
> Cheaper, and perhaps more accurate too? Don't recall if we have any code
> paths where the input timestamps are likely to be better-than-microsecond,
> but surely that's coming someday.
instr_time on !WIN32 use struct timespec, so we already should have nanosecond
precision available. IOW, we could add a INSTR_TIME_GET_NANOSEC today. Or am I
misunderstanding what you mean?
> I'm unsure that we want to deal with rdtsc's vagaries in general, but
> no objection to changing instr_time.
Cool.
Looking at the instr_time.h part of the change, I think it should go further,
and basically do the same thing in the WIN32 path. The only part that needs to
be be win32 specific is INSTR_TIME_SET_CURRENT(). That'd reduce duplication a
good bit.
Greetings,
Andres Freund