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Subject: Re: Odd IDE performance drop 2.4 vs 2.6?
From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Ondrej Zary <linux@rainbow-software.org>,
       Grant Coady <grant_lkml@dodo.com.au>,
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On Llu, 2005-06-13 at 15:06, Nick Piggin wrote:
> > Make sure you have pre-empt disabled and the antcipatory I/O scheduler
> > disabled. 
> > 
> I don't think that those could explain it.

Try it and see. The anticipatory I/O scheduler does horrible things to
my IDE streaming performance numbers and to swap performance. It tries
to merge I/O by delaying it which is deeply ungood when it comes to IDE
streaming even if its good for general I/O.

Alan