From mboxrd@z Thu Jan 1 00:00:00 1970 From: Josh Durgin Subject: Re: [PATCH REPOST 0/3] rbd: no need for file mapping calculation Date: Wed, 16 Jan 2013 18:34:54 -0800 Message-ID: <50F7634E.9010204@inktank.com> References: <50E6EC84.2060304@inktank.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from mail-pb0-f47.google.com ([209.85.160.47]:37932 "EHLO mail-pb0-f47.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757581Ab3AQCe6 (ORCPT ); Wed, 16 Jan 2013 21:34:58 -0500 Received: by mail-pb0-f47.google.com with SMTP id wz17so1090115pbc.34 for ; Wed, 16 Jan 2013 18:34:57 -0800 (PST) In-Reply-To: <50E6EC84.2060304@inktank.com> Sender: ceph-devel-owner@vger.kernel.org List-ID: To: Alex Elder Cc: "ceph-devel@vger.kernel.org" On 01/04/2013 06:51 AM, Alex Elder wrote: > Currently every osd request submitted by the rbd code undergoes a > file mapping operation, which is common with what the ceph file system > uses. But some analysis shows that there is no need to do this for > rbd, because it already takes care of its own blocking of image data > into distinct objects. Removing this simplifies things. I especially > think removing this improves things conceptually, removing a complex > mapping operation from the I/O path. > > -Alex > > [PATCH REPOST 1/3] rbd: pull in ceph_calc_raw_layout() > [PATCH REPOST 2/3] rbd: open code rbd_calc_raw_layout() > [PATCH REPOST 3/3] rbd: don't bother calculating file mapping We'll want to use similar methods later for fancier rbd striping with format 2 images, but that'll take more restructuring later anyway. This is fine for now. Reviewed-by: Josh Durgin