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From: Vasile Rotaru <vrotaru@seznam.cz>
To: 9fans@cse.psu.edu
Subject: Re: [9fans] hyperthreading
Date: Mon,  5 Jan 2004 11:03:34 +0000	[thread overview]
Message-ID: <bsn6bb$e4nr9$1@ID-216690.news.uni-berlin.de> (raw)
In-Reply-To: <Pine.LNX.4.44.0312280911230.31428-100000@maxroach.lanl.gov>

On Sun, 28 Dec 2003 17:12:48 +0100, ron minnich wrote:

> hyperthreading: don't waste your time.
> 
> hype-r-threading.
> 
> ron

Let's say if I understand it correctly.

I take a very simple example, say we need to fill a big array.

 case a: Single processor, single thread
   (the base case)

 case b: Single processor, two threads.
    (one fills the even, the other the odd positions).
     Slower, time lost in task switch.

 case c: Single HP processor two threads.
     A litle faster than in case b), since less time lost in task switch.

 case d) Two processors, two threads.
     Solid speed gain, almost two times faster.

 So I just can't think of a realistic scenario, where the speed of task
switching will be noticeable..

bas


  parent reply	other threads:[~2004-01-05 11:03 UTC|newest]

Thread overview: 17+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2003-12-26 23:05 andrey mirtchovski
2003-12-27  0:00 ` jmk
2003-12-27 18:39   ` jmk
2003-12-28 16:11   ` ron minnich
2003-12-28 22:12     ` Joel Salomon
2003-12-29  1:47       ` William Josephson
2003-12-31 17:08       ` ron minnich
2004-01-05 11:03     ` Vasile Rotaru [this message]
2004-01-05 14:31       ` David Presotto
2004-01-05 15:32         ` ron minnich
2003-12-27  4:10 ` [9fans] fossil/venti vdharani
2003-12-27  4:49   ` okamoto
2003-12-27  7:52     ` vdharani
2003-12-27  5:20       ` mirtchov
2003-12-28  4:47       ` okamoto
2003-12-28  8:22         ` vdharani
2003-12-28  6:40           ` andrey mirtchovski

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