From mboxrd@z Thu Jan 1 00:00:00 1970 From: Michele Brodoloni Subject: Re: bcache: bch_btree_gc() gc failed! Date: Fri, 7 Oct 2016 18:01:59 +0000 (UTC) Message-ID: References: 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]:49900 "EHLO blaine.gmane.org" rhost-flags-FAIL-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1755269AbcJGSCZ (ORCPT ); Fri, 7 Oct 2016 14:02:25 -0400 Received: from list by blaine.gmane.org with local (Exim 4.84_2) (envelope-from ) id 1bsZTL-0002Wt-Sb for linux-bcache@vger.kernel.org; Fri, 07 Oct 2016 20:02:15 +0200 Sender: linux-bcache-owner@vger.kernel.org List-Id: linux-bcache@vger.kernel.org To: linux-bcache@vger.kernel.org Ok.. I solved.. I just detached and reattached the cache # echo 7eb257b3-940d-42ca-ab23-52752f8b17f8 > /sys/block/bcache1/bcache/detach # echo 7eb257b3-940d-42ca-ab23-52752f8b17f8 > /sys/block/bcache1/bcache/attach that did the trick. # bcache-super-show /dev/sdd1 sb.magic ok sb.first_sector 8 [match] sb.csum 98719AA13E8D185F [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 1 [clean] cset.uuid 7eb257b3-940d-42ca-ab23-52752f8b17f8 # bcache-super-show /dev/sde1 sb.magic ok sb.first_sector 8 [match] sb.csum 98719AA13E8D185F [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 1 [clean] cset.uuid 7eb257b3-940d-42ca-ab23-52752f8b17f8 Everything is ok. Il Fri, 07 Oct 2016 12:55:50 +0000, Michele Brodoloni ha scritto: > Hi, > I tried to reboot the machine, but bcache is still dead. > /sys/block/bcache0/bcache/state reports "clean" (RAID5) > /sys/block/bcache1/bcache/state reports "no cache" (SAN RAID10) > > I did not mention before that the SAN is used like a DAS, and it isn't > shared with other machines. There's just one server accessing it. > > Regards, > Michele > > Il Fri, 07 Oct 2016 10:46:39 +0000, Michele Brodoloni ha scritto: > >> 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