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Date: Wed, 5 Dec 2001 16:22:38 -0200 (BRST)
From: Rik van Riel <riel@conectiva.com.br>
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To: Marcelo Tosatti <marcelo@conectiva.com.br>
Cc: Roy Sigurd Karlsbakk <roy@karlsbakk.net>, <linux-kernel@vger.kernel.org>
Subject: Re: /proc/sys/vm/(max|min)-readahead effect????
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On Wed, 5 Dec 2001, Marcelo Tosatti wrote:
> On Wed, 5 Dec 2001, Roy Sigurd Karlsbakk wrote:
>
> > I've just upgraded to 2.4.16 to get /proc/sys/vm/(max|min)-readahead
> > available. I've got this idea...
> >
> > If lots of files (some hundered) are read simultaously, I waste all the
> > i/o time in seeks. However, if I increase the readahead, it'll read more
> > data at a time, and end up with seeking a lot less.
>
> Do you also have VM pressure going on or do you have lots of free memory ?

I suspect the per-device readahead for IDE is limiting the
effect of vm_max_readahead ...

Rik
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