From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from cantor2.suse.de ([195.135.220.15]:57067 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751546AbbFYPbL (ORCPT ); Thu, 25 Jun 2015 11:31:11 -0400 Date: Thu, 25 Jun 2015 17:31:09 +0200 From: David Sterba To: Qu Wenruo Cc: dsterba@suse.cz, Facebook , linux-btrfs@vger.kernel.org Subject: Re: [PATCH RFC] btrfs: csum: Introduce partial csum for tree block. Message-ID: <20150625153109.GJ726@twin.jikos.cz> Reply-To: dsterba@suse.cz References: <1434078015-8868-1-git-send-email-quwenruo@cn.fujitsu.com> <557B076B.7050500@fb.com> <557E86A9.8040207@cn.fujitsu.com> <20150615131507.GL6761@twin.jikos.cz> <557F7A5F.5010206@cn.fujitsu.com> <557F8C78.7080304@cn.fujitsu.com> <55822008.1090305@cn.fujitsu.com> <1434643066.28534.0@mail.thefacebook.com> <20150618170632.GI6761@suse.cz> <55836FB3.1060704@cn.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <55836FB3.1060704@cn.fujitsu.com> Sender: linux-btrfs-owner@vger.kernel.org List-ID: On Fri, Jun 19, 2015 at 09:26:11AM +0800, Qu Wenruo wrote: > > I agree with that. I'm still not convinced that adding all the kernel > > code to repair the data is justified, compared to the block-level > > redundancy alternatives. > > Totally agree with this. > That's why we have support for RAID1/5/6/10. > > I also hate to add complexity to kernel codes, especially when the scrub > codes are already quite complex. > > But in fact, my teammate Zhao Lei is already doing some work to make > scrub codes clean and neat. Doing cleanups is a good thing regardless of new features, please don't hesitate to post them even if we do not agree to implement the partial csum/repair. I'm not against adding the partial csums & repair, but at the moment I'm not convinced.