From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S263653AbTFBUZI (ORCPT ); Mon, 2 Jun 2003 16:25:08 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262709AbTFBUZH (ORCPT ); Mon, 2 Jun 2003 16:25:07 -0400 Received: from ool-43524450.dyn.optonline.net ([67.82.68.80]:6664 "EHLO buggy.badula.org") by vger.kernel.org with ESMTP id S262373AbTFBUY0 (ORCPT ); Mon, 2 Jun 2003 16:24:26 -0400 Date: Mon, 2 Jun 2003 16:37:23 -0400 Message-Id: <200306022037.h52KbNVh012849@buggy.badula.org> From: Ion Badulescu To: "Vivek Goyal" Cc: , , , , , , Subject: Re: [NFS] Disabling Symbolic Link Content Caching in NFS Client In-Reply-To: <2BB7146B38D9CA40B215AB3DAAE24C080BA4F3@blr-m2-msg.wipro.com> User-Agent: tin/1.5.12-20020427 ("Sugar") (UNIX) (Linux/2.4.20 (i586)) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 28 May 2003 16:39:36 +0530, Vivek Goyal wrote: > I was following previous discussions in the mailing list and found that > caching mechanism affected hlfsd behavior. It looks like the problem was > resolved by updating mtime on every access. But still caching will lead > to a problem if two accesses are taking place in same jiffy. Yes, because the the nfs client is broken in this respect. noac should mean noac, but the nfs client will still cache attributes if the second access happens within the same jiffy as the previous access which updated the attribute cache. Replacing a couple of time_after() calls with time_after_eq() calls fixes the issue, at least for hlfsd. Of course, running with noac might be very much unacceptable if all you want is to avoid caching symlinks. > We are considering following design strategy to implement the parameter. > > 1. Make nfs_symlink_caching dynamically tunable using /proc and sysctl > interface. No. Do it on a per-mount basis, like the other OS's do. Ion -- It is better to keep your mouth shut and be thought a fool, than to open it and remove all doubt.