From: Alistair John Strachan <s0348365@sms.ed.ac.uk>
To: Claudio Scordino <cloud.of.andor@gmail.com>
Subject: Re: The "best" value of HZ
Date: Fri, 28 Oct 2005 03:31:21 +0100
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On Friday 28 October 2005 00:18, Claudio Scordino wrote:
> Hi,
>
>     during the last years there has been a lot of discussion about the
> "best" value of HZ... On i386 was 100, then became 1000, and finally was
> set to 250. I'm thinking to do an evaluation of this parameter using
> different architectures.
>
> Has anybody thought to give the possibility to modify the value of HZ at
> boot time instead of at compile time ? This would allow to easily test
> different values on different machines and create a table containing the
> "best" value for each architecture...  At this moment, instead, we have to
> recompile the kernel for each different value :(
>
> Do you think there would be much work to do that ?
> Do you think it would be a desired feature the knowledge of the best value
> for each architecture with more precision ?

Google for "dynticks". There's obviously an overhead associated with HZ not 
being a constant (the compiler cannot optimise many expressions), but the 
feature is being worked on nonetheless.

-- 
Cheers,
Alistair.

'No sense being pessimistic, it probably wouldn't work anyway.'
Third year Computer Science undergraduate.
1F2 55 South Clerk Street, Edinburgh, UK.
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