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From: Tijl Coosemans <tijl@ulyssis.org>
To: Ivan Voras <ivoras@freebsd.org>
Date: Sun, 7 Oct 2007 18:05:38 +0200
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Cc: freebsd-threads@freebsd.org
Subject: Re: Unexpected threading performance result
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On Sunday 07 October 2007 16:52:03 Ivan Voras wrote:
> For an unrelated purpose, I'm benchmarking performance of tree 
> algorithms in SMP environments and my preliminary run has an unexpected 
> result. Here's the typical output from the (small) benchmark program, 
> run on a dual-core Athlon64 (i386 mode):
> 
> Running benchmarks on small_nonuniform, 1000000 samples
> Step 1: Running 100 loops
> ** Step 1 benchmark completed 100 loops in 84.44 seconds.
> Step 2: Running 2 threads with 100 loops each
> ** Step 2 benchmark completed 100 loops in 2 threads in 167.46 seconds.

My guess is, that in the beginning of step1() and step2() you have to
add a line "time_start = gettime();".