From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.mystoragebox.com ([173.234.39.99]:50382 "EHLO mail.mystoragebox.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756574AbaIQRvx (ORCPT ); Wed, 17 Sep 2014 13:51:53 -0400 Received: from cpe-67-240-76-244.nycap.res.rr.com ([67.240.76.244] helo=[192.168.5.80]) by mail.mystoragebox.com with esmtpsa (TLS1.0:ECDHE_RSA_AES_128_CBC_SHA1:128) (Exim 4.83) (envelope-from ) id 1XUJOS-0002ii-4s for linux-btrfs@vger.kernel.org; Wed, 17 Sep 2014 13:51:52 -0400 Message-ID: <5419CA37.1070608@intellasoft.net> Date: Wed, 17 Sep 2014 13:51:51 -0400 From: Mark Murawski MIME-Version: 1.0 To: "linux-btrfs@vger.kernel.org" Subject: Re: btrfs balance enospc References: <54186A4B.60902@intellasoft.net> <54186A82.7070801@intellasoft.net>,<5760D61A-8550-4386-8125-0A29A81ADE3A@colorremedies.com> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Sender: linux-btrfs-owner@vger.kernel.org List-ID: > Does/should a balance imply removal of missing devices (as long as the minimum number of devices are still available)? That's a really good question. As a user I would expect it to balance over remaining devices assuming you still have a complete picture. Doing a device delete missing after a balance should be just some pool metadata updates at that point. Anyway... I solved my problem by moving/deleting files to free up space to the point that balance no longer complained about enospc. I suppose btrfs needs extra working space to do a balance... above and beyond the actual size of the existing data/metadata to be moved? I had a total of three devices, with what appeared to be plenty of space on the two that were to be remaining, but balance/remove was still complaining to be out of disk space. It would be a good idea for some metrics to be calculated upon start of a removal or balance to tell the user "hey you need to free up XXX more bytes in order for this operation to be successful".