From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from magic.merlins.org ([209.81.13.136]:57486 "EHLO mail1.merlins.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752640AbaCaQfl (ORCPT ); Mon, 31 Mar 2014 12:35:41 -0400 Date: Mon, 31 Mar 2014 09:35:31 -0700 From: Marc MERLIN To: linux-btrfs@vger.kernel.org, Filipe David Manana Cc: Chris Mason Message-ID: <20140331163531.GH2972@merlins.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <20140330002123.GP22552@merlins.org> Subject: Re: determining snapshot size -> adding "work to do" info to btrfs send Sender: linux-btrfs-owner@vger.kernel.org List-ID: On Sat, Mar 29, 2014 at 05:21:23PM -0700, Marc MERLIN wrote: > I had a look at > http://bj0z.wordpress.com/2011/04/27/determining-snapshot-size-in-btrfs/#comment-35 > but it's quite old and does not work anymore since userland became > incompatible with it. > > Has anyone seen something newer or have a newer fixed version of this? While watching a btrfs send|receive going for hours, keeping the backup disk array spinning in my living room, and my wondering "how far is it from being done", I was thinking: Would it be reasonably simple for btrfs send -p to have a few more features? 1) don't read all the data from disk, just read the metadata and tell me how many megabytes it will take to send. I can do this with btrfs send | wc -c I believe, but it would be better if it could do this without reading all the data blocks to send when I'm only caring about the byte output In turn this could be used to easily compute snapshot size diffs at least from one another. 2) output a list of files added/changed/removed, maybe with how much data is related to each. Arguably this would supersede 1) above even if it would be a little bit more work to do 3) when a real btrfs send is running, just like dd, I could send it a USR1 signal and it would output some kind of progress report. The Ted T'so motto (used for e2fsck) is "everything with a progress bar is faster" :) Note, the progress wouldn't have to be perfect, it could be by number of blocks, number of files, anything reasonably easy to implement it on. Does that sound reasonable? Thanks, Marc -- "A mouse is a device used to point at the xterm you want to type in" - A.S.R. Microsoft is to operating systems .... .... what McDonalds is to gourmet cooking Home page: http://marc.merlins.org/ | PGP 1024R/763BE901