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Date: Thu, 13 Jan 2005 20:52:10 +0100
From: Anthony Atkielski <atkielski.anthony@wanadoo.fr>
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Subject: Re: Hyperthreading hurts 5.3?
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Andrea Venturoli writes:

AV> Not exactly the same algorithm and on different set of data.

But similar machine instructions, perhaps?

AV> Yes.

Just the contention for the FPU alone might have had the effect of
single-threading the workload.  That plus the SMP overhead might give
you a zero or negative gain with HT.

AV> In the past.
AV> Nowadays they have some sort of protection.

Unfortunately, AMD lost my business when the first processor nearly
burst into flames.  I try not to make the same mistake twice.  And I've
seen examples of AMD processors that _have_ burst into flames, so why
take a chance?

For me the weakest parts of any machine are the fans and the disk
drives, because they have to move.

-- 
Anthony