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Date: Wed, 13 Jun 2001 14:20:26 +0200
From: Kurt Garloff <garloff@suse.de>
To: ognen@gene.pbi.nrc.ca
Cc: Christoph Hellwig <hch@ns.caldera.de>, linux-kernel@vger.kernel.org
Subject: Re: threading question
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In-Reply-To: <Pine.LNX.4.30.0106121304320.24593-100000@gene.pbi.nrc.ca>; from ognen@gene.pbi.nrc.ca on Tue, Jun 12, 2001 at 01:07:11PM -0600
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On Tue, Jun 12, 2001 at 01:07:11PM -0600, ognen@gene.pbi.nrc.ca wrote:
> due to the nature of the problem (a pairwise mutual alignment of n
> sequences results in mx. n^2 alignments which can each be done in a
> separate thread), I need to create and destroy the threads frequently.
>=20
> I am not really comfortable with 1.4 - 1.5 speedups since the solution was
> intended as a Linux one primarily and it just happenned that it works (and
> now even better) on Solaris/SGI/OSF...

Nor would I.=20

What I do in my numerics code to avoid this problem, is to create all the
threads (as many as there are CPUs) on program startup and have then wait
(block) for a condition. As soon as there's something to to, variables for
the thread are setup (protected by a mutex) and the thread gets signalled
(cond_signal).
If you're interested in the code, tell me.

This is supposed to be much faster than thread creation.

Regards,
--=20
Kurt Garloff  <garloff@suse.de>                          Eindhoven, NL
GPG key: See mail header, key servers         Linux kernel development
SuSE GmbH, Nuernberg, FRG                               SCSI, Security

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