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 X-Spam-Level: X-Spam-Status: No, score=-5.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2302DC433FE for ; Thu, 10 Dec 2020 01:58:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B949A23BC7 for ; Thu, 10 Dec 2020 01:58:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727524AbgLJB6W (ORCPT ); Wed, 9 Dec 2020 20:58:22 -0500 Received: from mx.ewheeler.net ([173.205.220.69]:47437 "EHLO mail.ewheeler.net" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727423AbgLJB6U (ORCPT ); Wed, 9 Dec 2020 20:58:20 -0500 X-Greylist: delayed 311 seconds by postgrey-1.27 at vger.kernel.org; Wed, 09 Dec 2020 20:58:20 EST Received: from localhost (localhost [127.0.0.1]) by mail.ewheeler.net (Postfix) with ESMTP id C4A8846 for ; Thu, 10 Dec 2020 01:52:22 +0000 (UTC) X-Virus-Scanned: amavisd-new at ewheeler.net Received: from mail.ewheeler.net ([127.0.0.1]) by localhost (mail.ewheeler.net [127.0.0.1]) (amavisd-new, port 10024) with LMTP id AXu8sw2E63Xh for ; Thu, 10 Dec 2020 01:52:22 +0000 (UTC) Received: from mx.ewheeler.net (mx.ewheeler.net [173.205.220.69]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.ewheeler.net (Postfix) with ESMTPSA id F24083E for ; Thu, 10 Dec 2020 01:52:21 +0000 (UTC) DKIM-Filter: OpenDKIM Filter v2.11.0 mail.ewheeler.net F24083E Date: Thu, 10 Dec 2020 01:52:19 +0000 (UTC) From: Eric Wheeler X-X-Sender: lists@pop.dreamhost.com To: linux-btrfs@vger.kernel.org Subject: Global reserve ran out of space at 512MB, fails to rebalance Message-ID: User-Agent: Alpine 2.21 (LRH 202 2017-01-01) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org Hello all, We have a 30TB volume with lots of snapshots that is low on space and we are trying to rebalance. Even if we don't rebalance, the space cleaner still fills up the Global reserve: Device size: 30.00TiB Device allocated: 30.00TiB Device unallocated: 1.00GiB Device missing: 0.00B Used: 29.27TiB Free (estimated): 705.21GiB (min: 704.71GiB) Data ratio: 1.00 Metadata ratio: 2.00 >>> Global reserve: 512.00MiB (used: 512.00MiB) <<<<<<< This was on a Linux 5.6 kernel. I'm trying a Linux 5.9.13 kernel with a hacked in SZ_4G in place of the SZ_512MB and will report back when I learn more. In the meantime, do you have any suggestions to work through the issue? Thank you for your help! -- Eric Wheeler