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Re: gettimeofday() does not returns usec resolution
- From: Lapo Luchini <lapo at lapo dot it>
- To: cygwin at cygwin dot com
- Date: Thu, 24 Jan 2002 22:34:26 +0100
- Subject: Re: gettimeofday() does not returns usec resolution
- References: <002e01c1a512$877216c0$0fa807d5@BRAMSCHE>
> > 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]
On my machine it's actually 1.74us, but I made the test on some machines and the result varies from 1.05 to 5.9us
(excluding a single machine for which it takes 11.45us).
That using my own profiles that uses the "adapted gettimeofday(), so it has a ilttle bit more of overhead to
divide it in the secs and usecs fileds.
--
Lapo 'Raist' Luchini
lapo@lapo.it (PGP & X.509 keys available)
http://www.lapo.it (ICQ UIN: 529796)
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