From: Boaz Harrosh Subject: Re: [PATCH V3 0/8] Cleancache: overview Date: Tue, 03 Aug 2010 19:22:36 +0300 Message-ID: <4C58424C.1020208@panasas.com> References: <20100621231809.GA11111@ca-server1.us.oracle.com4C49468B.40307@vflare.org> <840b32ff-a303-468e-9d4e-30fc92f629f8@default 20100723140440.GA12423@infradead.org 364c83bd-ccb2-48cc-920d-ffcf9ca7df19@default> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Cc: Christoph Hellwig , ngupta@vflare.org, akpm@linux-foundation.org, Chris Mason , viro@zeniv.linux.org.uk, adilger@sun.com, tytso@mit.edu, mfasheh@suse.com, Joel Becker , matthew@wil.cx, linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-ext4@vger.kernel.org, ocfs2-devel@oss.oracle.com, linux-mm@kvack.org, jeremy@goop.org, JBeulich@novell.com, Kurt Hackel , npiggin@suse.de, Dave Mccracken , riel@redhat.com, avi@redhat.com, Konrad Wilk To: Dan Magenheimer Return-path: In-Reply-To: Sender: owner-linux-mm@kvack.org List-Id: linux-ext4.vger.kernel.org On 07/24/2010 12:17 AM, Dan Magenheimer wrote: >>> On Fri, Jul 23, 2010 at 06:58:03AM -0700, Dan Magenheimer wrote: >>>> CHRISTOPH AND ANDREW, if you disagree and your concerns have >>>> not been resolved, please speak up. >> >> Hi Christoph -- >> >> Thanks very much for the quick (instantaneous?) reply! >> >>> Anything that need modification of a normal non-shared fs is utterly >>> broken and you'll get a clear NAK, so the propsal before is a good >>> one. >> >> No, the per-fs opt-in is very sensible; and its design is >> very minimal. > > Not to belabor the point, but maybe the right way to think about > this is: > > Cleancache is a new optional feature provided by the VFS layer > that potentially dramatically increases page cache effectiveness > for many workloads in many environments at a negligible cost. > > Filesystems that are well-behaved and conform to certain restrictions > can utilize cleancache simply by making a call to cleancache_init_fs > at mount time. Unusual, misbehaving, or poorly layered filesystems > must either add additional hooks and/or undergo extensive additional > testing... or should just not enable the optional cleancache. OK, So I maintain a filesystem in Kernel. How do I know if my FS is not "Unusual, misbehaving, or poorly layered" Thanks Boaz -- 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