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Message-ID: <3C507DE2.FBBD3BC@lapo.it>
Date: Thu, 24 Jan 2002 22:34:26 +0100
From: Lapo Luchini <lapo AT lapo DOT it>
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To: cygwin AT cygwin DOT com
Subject: Re: gettimeofday() does not returns usec resolution
References: <002e01c1a512$877216c0$0fa807d5 AT BRAMSCHE>
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> > 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 AT lapo DOT it (PGP & X.509 keys available)
http://www.lapo.it (ICQ UIN: 529796)



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