From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from plane.gmane.org ([80.91.229.3]:48278 "EHLO plane.gmane.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755442AbaD1Bs1 (ORCPT ); Sun, 27 Apr 2014 21:48:27 -0400 Received: from list by plane.gmane.org with local (Exim 4.69) (envelope-from ) id 1WeagE-0002CQ-E7 for linux-btrfs@vger.kernel.org; Mon, 28 Apr 2014 03:48:26 +0200 Received: from ip68-231-22-224.ph.ph.cox.net ([68.231.22.224]) by main.gmane.org with esmtp (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Mon, 28 Apr 2014 03:48:26 +0200 Received: from 1i5t5.duncan by ip68-231-22-224.ph.ph.cox.net with local (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Mon, 28 Apr 2014 03:48:26 +0200 To: linux-btrfs@vger.kernel.org From: Duncan <1i5t5.duncan@cox.net> Subject: Re: Confusing output of btrfs fi df Date: Mon, 28 Apr 2014 01:48:15 +0000 (UTC) Message-ID: References: <20140427153726.GA20596@mars> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-btrfs-owner@vger.kernel.org List-ID: Stefan Malte Schumacher posted on Sun, 27 Apr 2014 17:37:26 +0200 as excerpted: > Chris and Duncan: I tried both your suggestions but unfortunately > without success. Here is the output: > > mars:~ # btrfs balance start -susage=0 -f -v /mnt/btrfs/ > Dumping filters: flags 0xa, state 0x0, force is on > SYSTEM (flags 0x2): balancing, usage=0 > Done, had to relocate 0 out of 2708 chunks > > mars:~ # btrfs fi df /mnt/btrfs/ > Data, RAID1: total=2.64TiB, used=2.22TiB > System, RAID1: total=8.00MiB, used=380.00KiB > System, single: total=4.00MiB, used=0.00 > Metadata, RAID1: total=4.00GiB, used=2.94GiB > -------------------------------------------- > > mars:~ # btrfs balance start -sconvert=raid1,soft -f -v /mnt/btrfs/ > Dumping filters: flags 0xa, state 0x0, force is on > SYSTEM (flags 0x300): converting, target=16, soft is on > Done, had to relocate 0 out of 2708 chunks > > mars:~ # btrfs fi df /mnt/btrfs/ > Data, RAID1: total=2.64TiB, used=2.22TiB > System, RAID1: total=8.00MiB, used=380.00KiB > System, single: total=4.00MiB, used=0.00 > Metadata, RAID1: total=4.00GiB, used=2.94GiB OK, this is interesting It may be that you're reproducing something a couple other people saw earlier, but I've never seen here, which might be because I tend to do -m explicitly. So try this one: btrfs balance start -musage=0 -v (-f shouldn't be needed for this one because you're not doing -s specifically, and not forcing a lower redundancy level.) It may or may not free a couple metadata chunks too, but at least here, that's /exactly/ what I've used, and it has /never/ failed to cleanup that unused system chunk. If that fails to remove the extra system chunk, then we have a mystery indeed. What's different on your system and why isn't it working? If it succeeds in removing it, then we have a different and more limited bug/mystery. -s sometimes ignores system chunks it's documented to balance, while -m is doing both metadata and system, as expected. -- 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