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Date: Thu, 25 Aug 2005 12:30:15 -0400
From: "Justin R. Smith" <jsmith@drexel.edu>
To: freebsd-current@FreeBSD.org
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Cc: 
Subject: Hyperthreading degrades performance?
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This is in reply to the people who said this because of
cache-contention. Has anyone benchmarked this?

There's an article

http://www.2cpu.com/articles/41_1.html

that benchmarks hyperthreading in Linux and shows a modest (~29%)
improvement in performance --- depending on applications (with java
showing degradation of performance). Perhaps the linux sheduler does
things differently...