From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from westrelay02.boulder.ibm.com (westrelay02.boulder.ibm.com [9.17.195.11]) by e33.co.us.ibm.com (8.12.10/8.12.9) with ESMTP id j8CCrdvd019366 for ; Mon, 12 Sep 2005 08:53:40 -0400 Received: from d03av03.boulder.ibm.com (d03av03.boulder.ibm.com [9.17.195.169]) by westrelay02.boulder.ibm.com (8.12.10/NCO/VERS6.7) with ESMTP id j8CCrdHk468560 for ; Mon, 12 Sep 2005 06:53:39 -0600 Received: from d03av03.boulder.ibm.com (loopback [127.0.0.1]) by d03av03.boulder.ibm.com (8.12.11/8.13.3) with ESMTP id j8CCrcIT007823 for ; Mon, 12 Sep 2005 06:53:38 -0600 Date: Mon, 12 Sep 2005 18:23:28 +0530 From: Bharata B Rao Subject: Re: VM balancing issues on 2.6.13: dentry cache not getting shrunk enough Message-ID: <20050912125327.GB3804@in.ibm.com> Reply-To: bharata@in.ibm.com References: <20050911105709.GA16369@thunk.org> <20050911120045.GA4477@in.ibm.com> <20050912031636.GB16758@thunk.org> <210180000.1126505790@[10.10.2.4]> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <210180000.1126505790@[10.10.2.4]> Sender: owner-linux-mm@kvack.org Return-Path: To: "Martin J. Bligh" Cc: Theodore Ts'o , Dipankar Sarma , linux-mm@kvack.org, linux-kernel@vger.kernel.org List-ID: On Sun, Sep 11, 2005 at 11:16:30PM -0700, Martin J. Bligh wrote: > > > --Theodore Ts'o wrote (on Sunday, September 11, 2005 23:16:36 -0400): > > > On Sun, Sep 11, 2005 at 05:30:46PM +0530, Dipankar Sarma wrote: > >> Do you have the /proc/sys/fs/dentry-state output when such lowmem > >> shortage happens ? > > > > Not yet, but the situation occurs on my laptop about 2 or 3 times > > (when I'm not travelling and so it doesn't get rebooted). So > > reproducing it isn't utterly trivial, but it's does happen often > > enough that it should be possible to get the necessary data. > > > >> This is a problem that Bharata has been investigating at the moment. > >> But he hasn't seen anything that can't be cured by a small memory > >> pressure - IOW, dentries do get freed under memory pressure. So > >> your case might be very useful. Bharata is maintaing an instrumentation > >> patch to collect more information and an alternative dentry aging patch > >> (using rbtree). Perhaps you could try with those. > > > > Send it to me, and I'd be happy to try either the instrumentation > > patch or the dentry aging patch. > > Other thing that might be helpful is to shove a printk in prune_dcache > so we can see when it's getting called, and how successful it is, if the > more sophisticated stuff doesn't help ;-) > I have incorporated this in the dcache stats patch I have. I will post it tommorrow after adding some more instrumentation data (number of inuse and free dentries in lru list) and after a bit of cleanup and testing. Regards, Bharata. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org