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From: "Xin Zhao" <uszhaoxin@gmail.com>
To: linux-kernel <linux-kernel@vger.kernel.org>,
	linux-fsdevel@vger.kernel.org
Subject: Why will NFS client spend so much time on file open?
Date: Thu, 24 Aug 2006 03:15:38 -0400	[thread overview]
Message-ID: <4ae3c140608240015v6078fc29r287601aad7a2f1dc@mail.gmail.com> (raw)

Hi,

I did Apache benchmark and collected the performance results at the
file system call level.
The microbenchmark results were collected when I did "make" on Apache
source code.

The results are very interesting:

		      open	        read		
Total Time (s)  21.599 	         15.948 											Count		   310274 	
 98028 											Time/Call (ms)	69.61 	         162.69

The results show that NFS spent even more time on file open than on
file read. But this result confuses me: what does NFS do to open a
file? As far as I know, it just issues a lookup() RPC to get file
handle, and maybe a getattr() RPC to get file attributes. This should
not take so much time. Can someone explain why this could happen?

Thanks,
-x

             reply	other threads:[~2006-08-24  7:15 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2006-08-24  7:15 Xin Zhao [this message]
2006-08-24 21:36 ` Why will NFS client spend so much time on file open? Trond Myklebust

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