Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753763AbXIPWon (ORCPT ); Sun, 16 Sep 2007 18:44:43 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753854AbXIPWod (ORCPT ); Sun, 16 Sep 2007 18:44:33 -0400 Received: from lazybastard.de ([212.112.238.170]:41579 "EHLO longford.lazybastard.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753532AbXIPWoc (ORCPT ); Sun, 16 Sep 2007 18:44:32 -0400 Date: Mon, 17 Sep 2007 00:40:22 +0200 From: =?utf-8?B?SsO2cm4=?= Engel To: Goswin von Brederlow Cc: Joern Engel , Andrea Arcangeli , Andrew Morton , Nick Piggin , Christoph Lameter , torvalds@linux-foundation.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, Christoph Hellwig , Mel Gorman , William Lee Irwin III , David Chinner , Jens Axboe , Badari Pulavarty , Maxim Levitsky , Fengguang Wu , swin wang , totty.lu@gmail.com, hugh@veritas.com Subject: Re: [00/41] Large Blocksize Support V7 (adds memmap support) Message-ID: <20070916224022.GA3573@lazybastard.org> References: <20070911060349.993975297@sgi.com> <200709110452.20363.nickpiggin@yahoo.com.au> <20070911121225.GE13132@lazybastard.org> <20070915014449.4f9cdb51.akpm@linux-foundation.org> <87ir6c3z2l.fsf@informatik.uni-tuebingen.de> <20070915155100.GA21861@v2.random> <87tzpvy9cb.fsf@informatik.uni-tuebingen.de> <20070915223032.GA6708@v2.random> <20070916174657.GA2393@lazybastard.org> <87d4wi5kpr.fsf@informatik.uni-tuebingen.de> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <87d4wi5kpr.fsf@informatik.uni-tuebingen.de> User-Agent: Mutt/1.5.9i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1252 Lines: 29 On Mon, 17 September 2007 00:06:24 +0200, Goswin von Brederlow wrote: > > How probable is it that the dentry is needed again? If you copy it and > it is not needed then you wasted time. If you throw it out and it is > needed then you wasted time too. Depending on the probability one of > the two is cheaper overall. Idealy I would throw away dentries that > haven't been accessed recently and copy recently used ones. > > How much of a systems ram is spend on dentires? How much on task > structures? Does anyone have some stats on that? If it is <10% of the > total ram combined then I don't see much point in moving them. Just > keep them out of the way of users memory so the buddy system can work > effectively. As usual, the answer is "it depends". I've had up to 600MB in dentry and inode slabs on a 1GiB machine after updatedb. This machine currently has 13MB in dentries, which seems to be reasonable for my purposes. Jörn -- Audacity augments courage; hesitation, fear. -- Publilius Syrus - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/