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Re: [PATCH] Speed up profile reading/writing
- From: Jan Hubicka <jh at suse dot cz>
- To: Zdenek Dvorak <rakdver at atrey dot karlin dot mff dot cuni dot cz>
- Cc: gcc-patches at gcc dot gnu dot org, jh at suse dot cz, rth at redhat dot com
- Date: Thu, 27 Feb 2003 09:26:11 +0100
- Subject: Re: [PATCH] Speed up profile reading/writing
- References: <20030227011632.GA22595@atrey.karlin.mff.cuni.cz>
> the linux kernel does not cope well with a lot of small reads and writes
> produced by the profiling code. This gets significant if instrumented
> program is large and runs for only small amount of time -- profiling
> gcc spends about 50% of time in system when compiling testsuite during
> profiledbootstrap. This patch makes the program to read/write the whole
> .da files at once, thus improving speed in this case (admitedly
> patological one) by about 30%.
I tried profiledbootstrap with this patch and it works in good speed
now. I can use parallel make now too, so everything gets much smoother
than last week.