Subject: Re: O_DIRECT, O_SYNC, or fsync() on NFS mounts?
From: Trond Myklebust <trond.myklebust@fys.uio.no>
To: Kums <kumaran.rajaram@gmail.com>
Cc: Moazam Raja <moazam@gmail.com>, linux-nfs@vger.kernel.org
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Date: Mon, 22 Nov 2010 13:04:51 -0500
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On Mon, 2010-11-22 at 10:45 -0700, Kums wrote:
> On Sat, Nov 20, 2010 at 4:54 PM, Trond Myklebust <trond.myklebust@fys.uio.no
> > wrote:
> > If so, then that would be
> > a much stronger guarantee than POSIX and local disk give you, and it
> > will seriously impact I/O performance (whether you use NFS, local disk
> > or whatever).
> >
> 
> Yes, I understand. Iam just throwing out a suggestion to see if "-o sync"
> nfs mount + sync exportfs option can be alternative to using O_SYNC or
> O_DIRECT in the application (to guarantee everything written by application
> hits the disk).

mount -osync under NFS works exactly the same as under any other
filesystem, so yes...

Trond