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From: Ben Greear <greearb@candelatech.com>
To: linux-nfs@vger.kernel.org
Subject: Reading NFS file without copying to user-space?
Date: Fri, 04 Sep 2009 12:48:53 -0700	[thread overview]
Message-ID: <4AA16F25.6050700@candelatech.com> (raw)

I'm trying to optimize a tool that should do NFS reads as fast as possible
from a server in order to stress test the server.

Currently, I open the file as normal and read into a pre-allocated buffer.

This causes a copy of the data to user-space.

Is there any way to cause the nfs client logic to still request the file-read,
but not actually copy anything to user-space?

Maybe some trick with mmap would do this?

Thanks,
Ben

-- 
Ben Greear <greearb@candelatech.com>
Candela Technologies Inc  http://www.candelatech.com


             reply	other threads:[~2009-09-04 20:19 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-09-04 19:48 Ben Greear [this message]
2009-09-04 20:35 ` Reading NFS file without copying to user-space? Trond Myklebust
     [not found]   ` <1252096543.2402.4.camel-rJ7iovZKK19ZJLDQqaL3InhyD016LWXt@public.gmane.org>
2009-09-04 20:49     ` Ben Greear
2009-09-04 20:58       ` Trond Myklebust
2009-09-04 21:12         ` Ben Greear
2009-09-04 22:00           ` Trond Myklebust
2009-09-04 21:57         ` Ben Greear
2009-09-04 22:15           ` Trond Myklebust
     [not found]             ` <1252102506.5274.7.camel-rJ7iovZKK19ZJLDQqaL3InhyD016LWXt@public.gmane.org>
2009-09-04 22:30               ` Ben Greear
2009-09-04 22:49                 ` Trond Myklebust
2009-09-04 23:03                   ` Ben Greear

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