From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id B3E46C61DA4 for ; Sat, 11 Feb 2023 19:50:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229616AbjBKTul (ORCPT ); Sat, 11 Feb 2023 14:50:41 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33014 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229496AbjBKTuk (ORCPT ); Sat, 11 Feb 2023 14:50:40 -0500 Received: from mail.lichtvoll.de (luna.lichtvoll.de [194.150.191.11]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 26EE818ABA for ; Sat, 11 Feb 2023 11:50:36 -0800 (PST) Received: from 127.0.0.1 (localhost [127.0.0.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-384) server-digest SHA384) (No client certificate requested) by mail.lichtvoll.de (Postfix) with ESMTPSA id 35E225EEB85; Sat, 11 Feb 2023 20:50:34 +0100 (CET) From: Martin Steigerwald To: waxhead@dirtcellar.net, linux-btrfs , Forza Subject: Re: Never balance metadata? Date: Sat, 11 Feb 2023 20:50:33 +0100 Message-ID: <2626940.X9hSmTKtgW@lichtvoll.de> In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" Authentication-Results: mail.lichtvoll.de; auth=pass smtp.auth=martin smtp.mailfrom=martin@lichtvoll.de Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org Forza - 11.02.23, 18:18:50 CET: > On 2023-02-11 02:36, waxhead wrote: > > I have read several places, including on this mailing list that > > metadata is not supposed to be balanced unless converting between > > profiles. > > > > Interestingly enough there is nothing mentioned about this in the > > docs... https://btrfs.readthedocs.io/en/latest/btrfs-balance.html > > > > Should one still NOT balance metadata? If so - please update the > > docs > > with a explanation to why one should not do that. > > There is no direct issue with balancing metadata chunks. > > The recommendation to not balance metadata is because it can > contribute to a ENOSPC (no free space left) error. This happens when > Btrfs needs to allocate another metadata chunk, but there is no > unallocated space available. Thanks for that very good and thorough explanation. Something like this in the official documentation would be great! Best, -- Martin