From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jens Axboe Subject: Re: dm: pass up rotational flag Date: Thu, 26 May 2011 21:14:17 +0200 Message-ID: <4DDEA689.2090004@fusionio.com> References: <1306356648-30730-1-git-send-email-msb@chromium.org> <20110526182321.GA26219@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org To: "Martin K. Petersen" Cc: Mike Snitzer , Mandeep Singh Baines , "linux-kernel@vger.kernel.org" , "jrbarnette@chromium.org" , Neil Brown , Alasdair G Kergon , "dm-devel@redhat.com" List-Id: dm-devel.ids On 2011-05-26 20:29, Martin K. Petersen wrote: >>>>>> "Mike" == Mike Snitzer writes: > >>> Allow the NONROT flag to be passed through to linear mappings if all >>> underlying device are non-rotational. Tools like ureadahead will >>> schedule IOs differently based on the rotational flag. > > Mike> Thanks for doing this, looks good in general. > > I'd rather we made the rotational property part of the topology instead > of having to special-case it in DM. I seem to recall posting a patch > that did that at some point but I can't seem to find it... Agree, would be a better idea. -- Jens Axboe