From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-we0-f174.google.com ([74.125.82.174]:39453 "EHLO mail-we0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753696Ab2JCUYF (ORCPT ); Wed, 3 Oct 2012 16:24:05 -0400 Received: by weyt9 with SMTP id t9so4565940wey.19 for ; Wed, 03 Oct 2012 13:24:04 -0700 (PDT) Date: Wed, 3 Oct 2012 23:24:01 +0300 From: Ilya Dryomov To: Goffredo Baroncelli Cc: Chris Mason , "linux-btrfs@vger.kernel.org" , Goffredo Baroncelli Subject: Re: [PATCH][BTRFS-PROGS][V1] btrfs filesystem df Message-ID: <20121003202401.GC2890@zambezi.lan> References: <1349264596-9383-1-git-send-email-kreijack@inwind.it> <20121003150117.GA1978@zambezi.lan> <506C6BC8.5050809@gmail.com> <20121003174643.GB2890@zambezi.lan> <506C997C.5070301@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <506C997C.5070301@gmail.com> Sender: linux-btrfs-owner@vger.kernel.org List-ID: On Wed, Oct 03, 2012 at 10:01:00PM +0200, Goffredo Baroncelli wrote: > On 10/03/2012 07:46 PM, Ilya Dryomov wrote: > >On Wed, Oct 03, 2012 at 06:46:00PM +0200, Goffredo Baroncelli wrote: > >>On 10/03/2012 05:01 PM, Ilya Dryomov wrote: > >>>"Type" for the first column is probably enough. > >>> > >>>Why is the third column called Chunk-size? If my understanding is > >>>correct, it's just a break down of Disk_allocated from the summary > >>>section. If so, why not call it Disk_allocated to avoid confusion? > >> > >>Using everywhere Disk_ was my first attempt. But after > >>some thoughts I decided that these are two different kind of > >>information. It is true that Disk_allocated is the sum of > >>Chunk-Sizes... But my feels is that this is a kind of > >>"implementation details". If some other type of allocation unit will > >>be added to BTRFS, then these will be added to Disk_allocated, but > >>not to Chunk list... > >>I prefer to not change the wording until an enough critical mass of > >>people converge to a unique solution . > > > >It is the chunks that is the implementation detail that we want to hide. > >Average Btrfs user wouldn't want to know anything about chunks, the only > >thing he'd be interested in is Disk_allocated and similar fields. > > The "df" standard tool id sufficient for the "average user". > We need only to export these information via the standard syscall > stat[v]fs. Basically we should try to implement the algorithm of the > Free_(Estimated) space for the statfs(2) syscall. > Who uses btrfs tools, is an user with knowledge of btrfs higher than > the average. > > >Moreover, I am pretty sure "Chunk-Size" would actually confuse people. > >I stared at your example output for a few seconds trying to comprehend a > >21GB Chunk-Size on a 72GB partition. What you call "Chunk-Size" is > >actually a sum of sizes of chunks of that particular type, and a few > >lines above you call the same exact sum (only this time over all types > >of chunks) "Disk_allocated". So I think it's only logical to rename the > >column in question to "Disk_allocated" to match the summary section. > > What about > [...] > Details: > Chunk_type Mode Size_(disk) Size_(logical) Used > Data Single 21.01GB 21.01GB 10.53GB > System DUP 80.00MB 40.00MB 4.00KB > [...] > > ? This is definitely better. Can you also drop "Chunk_type" in favor of "Type"? Thanks, Ilya