From mboxrd@z Thu Jan  1 00:00:00 1970
From: Trond Myklebust <trond.myklebust@fys.uio.no>
Subject: Re: [PATCH 2/3] NFS: Add NFS_MOUNT_NONEGDE flag to avoid caching
	negative dentries
Date: Fri, 18 Jan 2008 16:17:04 -0500
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Cc: Bob Bell <b_linuxnfs-Y/+76LoPTq9wBoktGHYdvgC/G2K4zDHf@public.gmane.org>,
	"Muntz, Daniel" <Dan.Muntz@netapp.com>,
	Steve Dickson <SteveD@redhat.com>,
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To: Chuck Lever <chuck.lever@oracle.com>
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On Fri, 2008-01-18 at 16:12 -0500, Chuck Lever wrote:

> When would anyone want to use lookupcache=none -- what exactly would  
> it do?  How is it different than actimeo=0?

It would be very different. The idea of lookupcache=none would be to
turn off the directory mtime-based revalidation algorithm in
nfs_lookup_revalidate().
IOW: you would force an on-the-wire LOOKUP call for each dentry
revalidation.

Cheers
  Trond