Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1764343AbXJSVh0 (ORCPT ); Fri, 19 Oct 2007 17:37:26 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932127AbXJSVg5 (ORCPT ); Fri, 19 Oct 2007 17:36:57 -0400 Received: from ebiederm.dsl.xmission.com ([166.70.28.69]:42350 "EHLO ebiederm.dsl.xmission.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1765564AbXJSVgz (ORCPT ); Fri, 19 Oct 2007 17:36:55 -0400 From: ebiederm@xmission.com (Eric W. Biederman) To: Nick Piggin Cc: Chris Mason , Christian Borntraeger , Andrew Morton , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Martin Schwidefsky , "Theodore Ts'o" , stable@kernel.org Subject: Re: [RFC][PATCH] block: Isolate the buffer cache in it's own mappings. References: <200710151028.34407.borntraeger@de.ibm.com> <1192665785.15717.34.camel@think.oraclecorp.com> <200710181510.48382.nickpiggin@yahoo.com.au> Date: Fri, 19 Oct 2007 15:35:40 -0600 In-Reply-To: <200710181510.48382.nickpiggin@yahoo.com.au> (Nick Piggin's message of "Thu, 18 Oct 2007 15:10:48 +1000") Message-ID: User-Agent: Gnus/5.110006 (No Gnus v0.6) Emacs/21.4 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1099 Lines: 29 Nick Piggin writes: > > [*] The ramdisk code is simply buggy, right? (and not the buffer > cache) >From the perspective of the ramdisk it expects the buffer cache to simply be a user of the page cache, and thus the buffer cache is horribly buggy. >From the perspective of the buffer cache it still the block device cache in the kernel and it the way it works are the rules for how caching should be done in the kernel, and it doesn't give any mind to this new fangled page cache thingy. > The idea of your patch in theory is OK, but Andrew raises valid > points about potential coherency problems, I think. There are certainly implementation issues in various filesystems to overcome before remounting read-write after doing a fsck on a read-only filesystem will work as it does today. So my patch is incomplete. Eric - 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/