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Date: Sat, 21 Feb 2009 23:56:15 +0100 (CET)
From: Wojciech Puchar <wojtek@wojtek.tensor.gdynia.pl>
To: Junsuk Shin <junsukshin@gmail.com>
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Cc: freebsd-questions@freebsd.org
Subject: Re: read two files simultaneously
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> I'm just guessing inode structure, the physical file location on HDD
> might be related to this. But, if I read only one file, the size
> doesn't matter. Reading file (10M, 100M, 700M) gives constantly about
> 70MB/s, and the weird thing happens when I read 2 files of big size.

if you use O_DIRECT it's read from disk exactly as you specified, without 
readahead, so you do a lot of seeks.

simply use bigger buffer like 1MB