On 7 August 2015 at 14:24, Bruce Momjian <[email protected]> wrote:
> On Tue, Jun 30, 2015 at 09:00:44PM +0200, Andres Freund wrote:
> > * 2014-12-08 [519b075] Simon ..: Use GetSystemTimeAsFileTime directly in
> win32
> > 2014-12-08 [8001fe6] Simon ..: Windows: use
> GetSystemTimePreciseAsFileTime if ..
> > Timer resolution isn't a unimportant thing for people using explain?
>
> This all seemed very internals-only, e.g.:
>
> On most Windows systems this change will actually have no significant
> effect on
> timestamp resolution as the system timer tick is typically between 1ms
> and 15ms
> depending on what timer resolution currently running applications have
> requested. You can check this with clockres.exe from sysinternals.
> Despite the
> platform limiation this change still permits capture of finer
> timestamps where
> the system is capable of producing them and it gets rid of an
> unnecessary
> syscall.
>
> Was I wrong?
>
>
This does have a user visible change. Timestamps are now likely to have 6
digits after the decimal point, if they're on a version of windows which
supports GetSystemTimePreciseAsFileTime();
Master:
postgres=# select now();
now
-------------------------------
2015-08-09 01:14:01.959645+12
(1 row)
9.4.4
postgres=# select now();
now
----------------------------
2015-08-09 01:15:09.783+12
(1 row)
Regards
David Rowley
--
David Rowley http://www.2ndQuadrant.com/
<http://www.2ndquadrant.com/>
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