From mboxrd@z Thu Jan 1 00:00:00 1970 From: Michele Brodoloni Subject: bcache: bch_btree_gc() gc failed! Date: Fri, 7 Oct 2016 10:46:39 +0000 (UTC) Message-ID: Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Return-path: Received: from [195.159.176.226] ([195.159.176.226]:35949 "EHLO blaine.gmane.org" rhost-flags-FAIL-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1750866AbcJGKra (ORCPT ); Fri, 7 Oct 2016 06:47:30 -0400 Received: from list by blaine.gmane.org with local (Exim 4.84_2) (envelope-from ) id 1bsSgC-0002Sx-UL for linux-bcache@vger.kernel.org; Fri, 07 Oct 2016 12:47:04 +0200 Sender: linux-bcache-owner@vger.kernel.org List-Id: linux-bcache@vger.kernel.org To: linux-bcache@vger.kernel.org Hello, I have bcache running on a Debian 8.0 x86_64 with kernel 4.4.16. I got 2x Samsung PRO 850 250gb in hardware RAID0 acting as cache device for 1) a local RAID5 volume 2) a SAN RAID10 volume in active/backup multipath fiber channel I noticed today that SAN backing devices got detached from cache: # bcache-super-show /dev/sdc1 sb.magic ok sb.first_sector 8 [match] sb.csum 2D71F678442855F6 [match] sb.version 3 [cache device] dev.label (empty) dev.uuid c3dd7b4e-04e0-4578-a0ce-b35a5745e459 dev.sectors_per_block 1 dev.sectors_per_bucket 1024 dev.cache.first_sector 1024 dev.cache.cache_sectors 629144576 dev.cache.total_sectors 629145600 dev.cache.ordered yes dev.cache.discard no dev.cache.pos 0 dev.cache.replacement 0 [lru] cset.uuid 7eb257b3-940d-42ca-ab23-52752f8b17f8 # bcache-super-show /dev/sdd1 sb.magic ok sb.first_sector 8 [match] sb.csum 514C0F59BC7C1938 [match] sb.version 1 [backing device] dev.label (empty) dev.uuid 904aaaa4-473a-446d-aad5-4e55cde972a8 dev.sectors_per_block 1 dev.sectors_per_bucket 1024 dev.data.first_sector 16 dev.data.cache_mode 0 [writethrough] dev.data.cache_state 0 [detached] cset.uuid 00000000-0000-0000-0000-000000000000 # bcache-super-show /dev/sde1 sb.magic ok sb.first_sector 8 [match] sb.csum 514C0F59BC7C1938 [match] sb.version 1 [backing device] dev.label (empty) dev.uuid 904aaaa4-473a-446d-aad5-4e55cde972a8 dev.sectors_per_block 1 dev.sectors_per_bucket 1024 dev.data.first_sector 16 dev.data.cache_mode 0 [writethrough] dev.data.cache_state 0 [detached] cset.uuid 00000000-0000-0000-0000-000000000000 (Obviously /dev/sdd1 and /dev/sde1 are the same device but with different path) Another side effect is that my syslog, kern.log logfiles are eating all my root partition space with messages like this: Oct 7 12:27:31 lnx kernel: [2300151.278097] bcache: bch_btree_gc() gc failed! What can be done to troubleshoot this issue? Regards, Michele