From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751416AbXCDEgA (ORCPT ); Sat, 3 Mar 2007 23:36:00 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751427AbXCDEgA (ORCPT ); Sat, 3 Mar 2007 23:36:00 -0500 Received: from smtp.osdl.org ([65.172.181.24]:53765 "EHLO smtp.osdl.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751416AbXCDEf7 (ORCPT ); Sat, 3 Mar 2007 23:35:59 -0500 Date: Sat, 3 Mar 2007 20:35:56 -0800 From: Andrew Morton To: "Lee Revell" Cc: linux-kernel@vger.kernel.org Subject: Re: userspace pagecache management tool Message-Id: <20070303203556.8648c9a2.akpm@linux-foundation.org> In-Reply-To: <75b66ecd0703031835j5ff2846fpd4761a89f67fc2f1@mail.gmail.com> References: <20070303122935.f1ab0067.akpm@linux-foundation.org> <75b66ecd0703031716k5b9fd96br9ecd93f1fc3a6032@mail.gmail.com> <20070303173933.9f46459c.akpm@linux-foundation.org> <75b66ecd0703031835j5ff2846fpd4761a89f67fc2f1@mail.gmail.com> X-Mailer: Sylpheed version 2.2.7 (GTK+ 2.8.17; x86_64-unknown-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Sat, 3 Mar 2007 21:35:59 -0500 "Lee Revell" wrote: > On 3/3/07, Andrew Morton wrote: > > But yes, updatedb's pagecache usage will be mainly metadata, and this tool > > doesn't address metadata pagecache, although it could do so. > > > > With no kernel changes? How? I can't find an equivalent API to > posix_fadvise() for metadata. > We can use mincore and fadvise against /dev/sda1, too. mincore's linear search would hurt but you could just run fadvise regularly. A lot of the blockdev pagecache is pretty useless anyway: we've already copied it much of it into dentries and inodes, and some of ext2/3/4's pagecache is already pinned by the fs.