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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> |
> > 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) -- Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple Bug reporting: http://cygwin.com/bugs.html Documentation: http://cygwin.com/docs.html FAQ: http://cygwin.com/faq/
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