From owner-freebsd-current@FreeBSD.ORG  Tue Jul  3 00:51:16 2007
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Date: Mon, 02 Jul 2007 19:35:11 -0500
From: Stephen Montgomery-Smith <stephen@math.missouri.edu>
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Subject: great job with multithreaded programs
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I did a recent upgrade of current, and a multithreaded program which 
used to take 33s suddenly takes 18s.  Somebody did something very right!!!

I can provide details (but please email me directly as I don't subscribe 
to current), but basically the program does these massively large 3D 
Fourier transforms using the math/fftw3 port.  I have two dual Xeon's 
with HT running, and I run fftw3 with 4 threads.  I use the ULE 
scheduler, and have witness and invariants all switched off.

I should add, perhaps disappointingly, that this now only brings FreeBSD 
on par with Linux with respect to this program - Red Hat Linux also ran 
this at 18s.  But hopefully this is part of some rather skillful 
reworking of multithreading on FreeBSD and we will see great gains in 
the future.

Best regards, Stephen