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Date: Tue, 29 May 2007 06:00:18 +0000
From: 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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Ståle Kristoffersen 写道:
> 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.
>
>   
no, I already set this.
#sysctl vfs.zfs.prefetch_disable
vfs.zfs.prefetch_disable: 1