Date: Thu, 17 Mar 2011 09:40:19 +1100
From: NeilBrown <neilb@suse.de>
To: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: Bryan Schumaker <bjschuma@netapp.com>,
        Chuck Lever <chuck.lever@oracle.com>,
        Linux NFS Mailing List <linux-nfs@vger.kernel.org>
Subject: Re: Use of READDIRPLUS on large directories
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On Wed, 16 Mar 2011 17:42:35 -0400 Trond Myklebust
<Trond.Myklebust@netapp.com> wrote:

 
> > So it is obvious that there is sometimes value in using readdirplus,
> > it is equally obvious that there is sometimes a cost.
> > 
> > Switching the default from "not paying the cost when it is big" to
> > "always paying the cost" is wrong.
> 
> That's what the nordirplus mount flag is for. Keeping an arbitrary limit
> in the face of evidence that it is hurting is equally wrong.
> 

If people didn't need 'nordirplus' previously to get acceptable
performance, and do need it now, then that is a regression.

NeilBrown