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RE: gettimeofday() does not returns usec resolution
- From: "Ralf Habacker" <Ralf dot Habacker at freenet dot de>
- To: "Cygwin" <cygwin at sources dot redhat dot com>
- Date: Thu, 24 Jan 2002 22:44:38 +0100
- Subject: RE: gettimeofday() does not returns usec resolution
>
> >
> >
> > > Hmm. I do remember this patch. Can you submit this to cygwin-patches
> > > in the correct format: http://cygwin.com/contrib.html ?
> >
> > Given enough time, yes (never hacked that one, but it seems that only
> > winsup/cygwin/times.cc would need to be modified).. anyway of course I'm one of
> > the few that actually would like to have this feature so I guess there's no big
> > hurry.
> >
> > Of course the number reported by PerformanceTimer has an unknown offset with
> > system time (it appears to start at 0 at program start, but that's not clearly
> > specified) so I would have calculate an initial "offset" in the "old" way... this
> > would give 3-4 microsecond precision on "deltas" but an initial uncertainty of
> ^^^^^
> > the usual 15 milliseconds or so.
> >
> This is a output of the mentioned profiler. It say about a minimal time of about 1-2 us. May the difference be
> caused by the cygwin.dll overhead ? (We're using the native functions, not gettimeofday()).
>
> [1828] EmptyTest count: 100 time: (min) 1 [us] (max) 2 [us] (sum) 169 [us]
>
Ups, I forgot to say I'm using win2k. Sorry
Ralf
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