Message-ID: <423EA611.3030409@imag.fr>
Date: Mon, 21 Mar 2005 11:46:41 +0100
From: Raphael Jacquot <raphael.jacquot@imag.fr>
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To: Xin Zhao <uszhaoxin@gmail.com>
CC: linux-kernel@vger.kernel.org
Subject: Re: Why is NFS write so slow?
References: <4ae3c1405032100293ff52077@mail.gmail.com>
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Xin Zhao wrote:
> Sorry for the dumb question. 
> 
> I am trying to develop a new filesystem based on NFS, which runs in a
> very fast network environment. I used the source code of NFS2, but
> noticed that NFS write is very slow. Even if I changed wsize to 8192,
> it still can only reach 1MB/s. I don't know why. Because the network
> is extremely fast (over 100MB/s), I don't think network is the only
> reason. Any other reason?
> 
> Is the NFS write synchronous? Does that means the NFS server will not
> return before the data is flushed to disk?  Because nfsd_write will
> close the file every time, I will assume that the data will be flushed
> to disk before return. However, even if I change nfsd_write to stop
> closing file, the write speed is still very slow. Can someone give me
> some advice about this?
> 
> Thanks in advance!

because NFS is now at version 4, so you're 2 versions late ?
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