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Date: | Thu, 3 Sep 2009 08:34:45 -0400 |
Message-ID: | <dd5f2deb0909030534v4dbc046epe22814476d8b1b70@mail.gmail.com> |
Subject: | Re: Simple bash script is slow to execute - appears to be time spent starting commands like ls |
From: | Lee <ler762 AT gmail DOT com> |
To: | cygwin AT cygwin DOT com |
Cc: | "Thrall, Bryan" <bryan DOT thrall AT flightsafety DOT com> |
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On 9/2/09, David Tazartes wrote: > Bryan Thrall wrote: > > You're right about true being built-in, but we still don't know from > your examples whether the problem is from forking or from IO. Try > replacing 'true' in Jeremy's loop with '/bin/true'. Comparison between > the two should give us an idea of the forking cost, without IO getting > in the way. > > ----- > > I had to reduce to 100 iterations. > > On Linux: > > real 0m0.448s > user 0m0.244s > sys 0m0.220s > > On Cygwin: > > real 0m48.411s > user 0m15.005s > sys 0m18.520s > > So basically a factor of 100... again points to forking or Vista process > start slowness. I couldn't resist playing along at home on a Windows XP machine :) It doesn't seem to be just a Windows Vista problem: $ time for n in $(seq 1 10000); do /bin/true; done real 3m6.641s user 5m36.750s sys 1m49.580s $ time for n in $(seq 1 10000); do true; done real 0m0.453s user 0m0.421s sys 0m0.046s $ uname -a CYGWIN_NT-5.1 33LTLG 1.5.25(0.156/4/2) 2008-06-12 19:34 i686 Cygwin Lee -- Problem reports: http://cygwin.com/problems.html FAQ: http://cygwin.com/faq/ Documentation: http://cygwin.com/docs.html Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple
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