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Date: Sat, 5 Jan 2002 18:12:59 -0800 (PST)
From: Davide Libenzi <davidel@xmailserver.org>
X-X-Sender: davide@blue1.dev.mcafeelabs.com
To: Alan Cox <alan@lxorguk.ukuu.org.uk>
cc: Ingo Molnar <mingo@elte.hu>, Linus Torvalds <torvalds@transmeta.com>,
        lkml <linux-kernel@vger.kernel.org>
Subject: Re: [announce] [patch] ultra-scalable O(1) SMP and UP scheduler
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On Sun, 6 Jan 2002, Alan Cox wrote:

> > Ingo, you don't need that many queues, 32 are more than sufficent.
> > If you look at the distribution you'll see that it matters ( for
> > interactive feel ) only the very first ( top ) queues, while lower ones
> > can very easily tollerate a FIFO pickup w/out bad feelings.
>
> 64 queues costs a tiny amount more than 32 queues. If you can get it down
> to eight or nine queues with no actual cost (espcially for non realtime queues)
> then it represents a huge win since an 8bit ffz can be done by lookup table
> and that is fast on all processors

It's here that i want to go, but i'd liketo do it gradually :)

unsigned char first_bit[255];




- Davide


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