From: Jos Hulzink <josh@stack.nl>
To: Con Kolivas <kernel@kolivas.org>,
       linux kernel mailing list <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] 2.6.1 Hyperthread smart "nice"
Date: Thu, 29 Jan 2004 10:39:22 +0100
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On Thursday 29 Jan 2004 09:17, Con Kolivas wrote:
> Hi all
>
> This patch (together with the ht base patch) will not allow a priority >10
> difference to run concurrently on both siblings, instead putting the low
> priority one to sleep. Overall if you run concurrent nice 0 and nice 20
> tasks with this patch your cpu throughput will drop during heavy periods by
> up to 10% (the hyperthread benefit), but your nice 0 task will run about
> 90% faster. It has no effect if you don't run any tasks at different "nice"
> levels. It does not modify real time tasks or kernel threads, and will
> allow niced tasks to run while a high priority kernel thread is running on
> the sibling cpu.

If I read you correctly, if one thread has nothing else to do but the nice 0 
task, the nice 20 task will never be scheduled at all ? Sounds like not the 
perfect solution to me...

Jos

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