how? as i see, discard is disabled... # cat /sys/block/sdc/bcache/discard 0 # ./bcache-status -s | grep Discard Discard? False 2015-08-15 21:12 GMT+03:00 Stefan Priebe - Profihost AG <s.priebe@xxxxxxxxxxxx>: > Disable discard ;-) no fix available. > > Stefan > > Excuse my typo sent from my mobile phone. > > Am 15.08.2015 um 19:54 schrieb Георгий Стариков <gstarikov@xxxxxxxxx>: > > Hi! > I lost bcache device after a reboot and dmesg contains the following: > [ 26.991085] bcache: prio_read() bad csum reading priorities > [ 26.991088] bcache: prio_read() bad magic reading priorities > [ 26.991425] attempt to access beyond end of device > [ 26.991428] sdc: rw=48, want=3405010361836132352, limit=468862128 > [ 26.991430] bcache: error on 4ca0fbc9-d20b-4a3d-bbd1-38d9a5810c27: > accessing priorities, > disabling caching > > how to fix it? > > i am using the following fix (recreate cache device with the old cuid) > and it works till next reboot. > > # bcache-super-show /dev/sdc > sb.magic ok > sb.first_sector 8 [match] > sb.csum F19B35ED4C357841 [match] > sb.version 3 [cache device] > > dev.label (empty) > dev.uuid 7dddbf16-ca58-48e3-82d8-da47ae7726dc > dev.sectors_per_block 1 > dev.sectors_per_bucket 1024 > dev.cache.first_sector 1024 > dev.cache.cache_sectors 468860928 > dev.cache.total_sectors 468861952 > dev.cache.ordered yes > dev.cache.discard no > dev.cache.pos 0 > dev.cache.replacement 0 [lru] > > cset.uuid 4ca0fbc9-d20b-4a3d-bbd1-38d9a5810c27 > > # make-bcache -C --cset-uuid 4ca0fbc9-d20b-4a3d-bbd1-38d9a5810c27 /dev/sdc > Already a bcache device on /dev/sdc, overwrite with --wipe-bcache > > make-bcache -C --wipe-bcache --cset-uuid > 4ca0fbc9-d20b-4a3d-bbd1-38d9a5810c27 /dev/sdc > Device /dev/sdc already has a non-bcache superblock, remove it using > wipefs and wipefs -a > > # wipefs -a /dev/sdc > > # make-bcache -C --wipe-bcache --cset-uuid > 4ca0fbc9-d20b-4a3d-bbd1-38d9a5810c27 /dev/sdc > UUID: f7d97543-69ea-4636-a4ff-ab925ab5abdd > Set UUID: 4ca0fbc9-d20b-4a3d-bbd1-38d9a5810c27 > version: 0 > nbuckets: 457873 > block_size: 1 > bucket_size: 1024 > nr_in_set: 1 > nr_this_dev: 0 > first_bucket: 1 > > # echo /dev/sdc > /sys/fs/bcache/register > > dmesg: > [42999.742342] bcache: run_cache_set() invalidating existing data > [42999.900046] bcache: bch_cached_dev_attach() Caching md0 as bcache0 > on set 4ca0fbc9-d20b-4a3d-bbd1-38d9a5810c27 > [42999.900067] bcache: register_cache() registered cache device sdc > [43002.019693] EXT4-fs (bcache0): recovery complete > [43002.043362] EXT4-fs (bcache0): mounted filesystem with ordered data > mode. Opts: discard,errors=remount-ro > > and final steps: > # echo writethrough > /sys/block/bcache0/bcache/cache_mode > # echo 128k > /sys/block/bcache0/bcache/sequential_cutoff > > # ./bcache-status -s > --- bcache --- > Device /dev/bcache0 (251:0) > UUID 4ca0fbc9-d20b-4a3d-bbd1-38d9a5810c27 > Block Size 0.50KiB > Bucket Size 512.00KiB > Congested? False > Read Congestion 2.0ms > Write Congestion 20.0ms > Total Cache Size 223.57GiB > Total Cache Used 2.24GiB (0%) > Total Cache Unused 221.34GiB (99%) > Dirty Data 0B (0%) > Evictable Cache 223.57GiB (100%) > Replacement Policy [lru] fifo random > Cache Mode [writethrough] writeback writearound none > Total Hits 139 (3%) > Total Misses 3816 > Total Bypass Hits 0 > Total Bypass Misses 0 > Total Bypassed 0B > --- Backing Device --- > Device /dev/md0 (9:0) > Size 5.46TiB > Cache Mode [writethrough] writeback writearound none > Readahead 0 > Sequential Cutoff 128.00KiB > Merge sequential? False > State clean > Writeback? True > Dirty Data 0B > Total Hits 139 (3%) > Total Misses 3816 > Total Bypass Hits 0 > Total Bypass Misses 0 > Total Bypassed 0B > --- Cache Device --- > Device /dev/sdc (8:32) > Size 223.57GiB > Block Size 0.50KiB > Bucket Size 512.00KiB > Replacement Policy [lru] fifo random > Discard? False > I/O Errors 0 > Metadata Written 1.60MiB > Data Written 19.20MiB > Buckets 457873 > Cache Used 2.24GiB (0%) > Cache Unused 221.34GiB (99%) > -- > To unsubscribe from this list: send the line "unsubscribe linux-bcache" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-bcache" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html