From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from plane.gmane.org ([80.91.229.3]:40426 "EHLO plane.gmane.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S966210AbbLQBJf (ORCPT ); Wed, 16 Dec 2015 20:09:35 -0500 Received: from list by plane.gmane.org with local (Exim 4.69) (envelope-from ) id 1a9N4W-0002I6-Dx for linux-btrfs@vger.kernel.org; Thu, 17 Dec 2015 02:09:32 +0100 Received: from ip98-167-165-199.ph.ph.cox.net ([98.167.165.199]) by main.gmane.org with esmtp (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Thu, 17 Dec 2015 02:09:32 +0100 Received: from 1i5t5.duncan by ip98-167-165-199.ph.ph.cox.net with local (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Thu, 17 Dec 2015 02:09:32 +0100 To: linux-btrfs@vger.kernel.org From: Duncan <1i5t5.duncan@cox.net> Subject: Re: [PATCH v3] btrfs: Introduce new mount option to disable tree log replay Date: Thu, 17 Dec 2015 01:09:21 +0000 (UTC) Message-ID: References: <1449714846-18174-1-git-send-email-quwenruo@cn.fujitsu.com> <20151214173200.GO4227@twin.jikos.cz> <5670C017.5010104@cn.fujitsu.com> <1450266300.6259.2.camel@scientia.net> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-btrfs-owner@vger.kernel.org List-ID: Christoph Anton Mitterer posted on Wed, 16 Dec 2015 12:45:00 +0100 as excerpted: > On Wed, 2015-12-16 at 11:10 +0000, Duncan wrote: >> And noload doesn't have the namespace collision problem norecovery does >> on btrfs, so I'd strongly suggest using it, at least as an alias for >> whatever other btrfs-specific name we might choose. > > but noload is, AFAIU, not what's desired here, is it? > Per manpage it's "Don't load the journal on mounting",... not only > wouldn't that fit for btrfs, it's also not what's really desired, i.e. > an option that implies everything necessary to not modify the device. Well, "don't load the journal on mounting" is exactly what the option would do. The journal (aka log) of course has a slightly different meaning, it's only the fsync log, but loading it is exactly what the option would prevent, here. Of course that isn't to say there shouldn't be another option, call it nomodify, for argument, that includes this and perhaps other options that would otherwise trigger filesystem level changes on a normal read-only mount. Too bad we can't simply rename the recovery mount option so norecovery could be used as well, but I guess that could potentially break too many existing deployments. =:^( -- Duncan - List replies preferred. No HTML msgs. "Every nonfree program has a lord, a master -- and if you use the program, he is your master." Richard Stallman