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Date: Wed, 15 Dec 2004 21:47:23 +0200
From: Petri Helenius <pete@he.iki.fi>
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To: Julian Elischer <julian@elischer.org>
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Subject: Re: worker thread performance question
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Julian Elischer wrote:

>
>
> Petri Helenius wrote:
>
>>
>> With libpthread is it usually optimal to have as many worker threads 
>> (CPU bound stuff) as kern.threads.virtual_cpu or have, say double the 
>> number so that there is always a thread in the run queue when another 
>> hits a mutex or sleep? 
>
>
> Are they always runnable?

Almost, except when they run into shared structures which obviously are 
minimized by design.

> theoretically you can schedule as many as you want.
> any number > NCPU should keep teh system busy, but
> I'm not sure I fully understand the question.

The question was aimed towards if larger runqueue takes more CPU to 
maintain than a shorter one does and if threads are involuntarily switched.

Pete

>
>>
>>
>> Pete
>>
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