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From: =?iso-8859-1?Q?St=E5le?= Kristoffersen <staalebk@ifi.uio.no>
To: Huang wen hui <huang@gddsn.org.cn>
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Cc: current@freebsd.org
Subject: Re: zfs generate a lot of IO ?
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On 2007-05-27 at 10:28, Huang wen hui wrote:
> hi,
> I install CURRENT with zfs root fs on my notebook(T60P). GENERIC
> configuration
> without INVARIANTS and WITNESS.
> I run a program to test. This program basically read a few small files
> and calcuate and output a small file.
> On FreeBSD6.2, iostat show that It generate a few io operation.
> But on zfs, generate a lot:

<snip>

This could be the same thing Nick Gustas and I have been seeing. Try
setting vfs.zfs.prefetch_disable="1" in loader.conf, this made things
"normal" for me.

-- 
Ståle Kristoffersen
staalebk@ifi.uio.no