Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934729AbdC3VLT (ORCPT ); Thu, 30 Mar 2017 17:11:19 -0400 Received: from mail-wr0-f194.google.com ([209.85.128.194]:36087 "EHLO mail-wr0-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754346AbdC3VLQ (ORCPT ); Thu, 30 Mar 2017 17:11:16 -0400 Subject: Re: [RFC PATCH v1 00/30] fs: inode->i_version rework and optimization To: Jeff Layton , "J. Bruce Fields" References: <20170320214327.GA5098@fieldses.org> <20170321134500.GA1318@infradead.org> <20170321163011.GA16666@fieldses.org> <1490117004.2542.1.camel@redhat.com> <20170321183006.GD17872@fieldses.org> <1490122013.2593.1.camel@redhat.com> <20170329111507.GA18467@quack2.suse.cz> <1490810071.2678.6.camel@redhat.com> <20170330064724.GA21542@quack2.suse.cz> <1490872308.2694.1.camel@redhat.com> <20170330161231.GA9824@fieldses.org> <1490898932.2667.1.camel@redhat.com> Cc: Jan Kara , Christoph Hellwig , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-nfs@vger.kernel.org, linux-ext4@vger.kernel.org, linux-btrfs@vger.kernel.org, linux-xfs@vger.kernel.org From: Boaz Harrosh Message-ID: <42bec37f-670c-3ea1-f2aa-7cecd619ad7e@gmail.com> Date: Fri, 31 Mar 2017 00:11:11 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.4.0 MIME-Version: 1.0 In-Reply-To: <1490898932.2667.1.camel@redhat.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 550 Lines: 17 On 03/30/2017 09:35 PM, Jeff Layton wrote: <> > Yeah, I imagine we'd need a on-disk change for this unless there's > something already present that we could use in place of a crash counter. > Perhaps we can use s_mtime and/or s_wtime in some way, I'm not sure what is a parallel for that in xfs. s_mtime - time-of-last mount s_wtime - time-of-last mount, umount, freez, unfreez, remount, ... Of course you'll need a per FS vector to access that. But this will need some math foo to get the bits compacted correctly just a thought. Thanks Boaz