From mboxrd@z Thu Jan 1 00:00:00 1970 From: Joel Becker Subject: Re: Filesystem hints to storage Date: Thu, 22 Jul 2010 12:15:41 -0700 Message-ID: <20100722191541.GA12376@mail.oracle.com> References: <20100722180854.GB22009@parisc-linux.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org To: Matthew Wilcox Return-path: Content-Disposition: inline In-Reply-To: <20100722180854.GB22009@parisc-linux.org> Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-fsdevel.vger.kernel.org On Thu, Jul 22, 2010 at 12:08:54PM -0600, Matthew Wilcox wrote: > For Enterprise NVMHCI, the working group is looking at refining these > hints. Are there any hints that people would like to see added or > removed from the list in NVMHCI 1.0? > > I think there are some hints that are hard for the filesystem to know > itself, never mind pass down, so it'd be good to remove them to reduce > the complexity. Contrariwise, there are some hints I think the filesystem > could pass down that aren't in the spec today, such as the flags from > madvise (random access vs sequential access) and whether the access is > for fs metadata or application data. If we're looking at the filesystem interface to all of this, I would think these hints could be used by non-SSD storage as well. Not only would a storage array benefit from knowing about random vs sequential access, but expected redundancy hints would be huge in managing utilization. Joel -- Life's Little Instruction Book #396 "Never give anyone a fruitcake." Joel Becker Consulting Software Developer Oracle E-mail: joel.becker@oracle.com Phone: (650) 506-8127