Any update on this? I have here exactly the same issue. Kernel 3.12.5-1-ARCH, backing device 500 GB IDE, cache 24 GB SSD => /dev/bcache0 On /dev/bcache I also have 2 subvolumes, / and /home. I get lots of messages in dmesg:
(...) [ 22.282469] BTRFS info (device bcache0): csum failed ino 56193 off 212992 csum 519977505 expected csum 3166125439 [ 22.282656] incomplete page read in btrfs with offset 1024 and length 3072 [ 23.370872] incomplete page read in btrfs with offset 1024 and length 3072 [ 23.370890] BTRFS info (device bcache0): csum failed ino 57765 off 106496 csum 3553846164 expected csum 1299185721 [ 23.505238] incomplete page read in btrfs with offset 2560 and length 1536 [ 23.505256] BTRFS info (device bcache0): csum failed ino 75922 off 172032 csum 1883678196 expected csum 1337496676 [ 23.508535] incomplete page read in btrfs with offset 2560 and length 1536 [ 23.508547] BTRFS info (device bcache0): csum failed ino 74368 off 237568 csum 2863587994 expected csum 2693116460 [ 25.683059] incomplete page read in btrfs with offset 2560 and length 1536 [ 25.683078] BTRFS info (device bcache0): csum failed ino 123709 off 57344 csum 1528117893 expected csum 2239543273 [ 25.684339] incomplete page read in btrfs with offset 1024 and length 3072 [ 26.622384] incomplete page read in btrfs with offset 1024 and length 3072 [ 26.906718] incomplete page read in btrfs with offset 2560 and length 1536 [ 27.823247] incomplete page read in btrfs with offset 1024 and length 3072 [ 27.823265] btrfs_readpage_end_io_hook: 2 callbacks suppressed [ 27.823271] BTRFS info (device bcache0): csum failed ino 34587 off 16384 csum 1180114025 expected csum 474262911 [ 28.490066] incomplete page read in btrfs with offset 2560 and length 1536 [ 28.490085] BTRFS info (device bcache0): csum failed ino 65817 off 327680 csum 3065880108 expected csum 2663659117 [ 29.413824] incomplete page read in btrfs with offset 1024 and length 3072 [ 41.913857] incomplete page read in btrfs with offset 2560 and length 1536 [ 55.761753] incomplete page read in btrfs with offset 1024 and length 3072 [ 55.761771] BTRFS info (device bcache0): csum failed ino 72835 off 81920 csum 1511792656 expected csum 3733709121 [ 69.636498] incomplete page read in btrfs with offset 2560 and length 1536 (...) should I be worried? thanks, Fabio Pfeifer 2013/12/18 eb <[email protected]>: > I've recently setup a system (Kernel 3.12.5-1-ARCH) which is layered as > follows: > > /dev/sdb3 - cache0 (80 GB Intel SSD) > /dev/sdc1 - backing device (2 TB WD HDD) > > sdb3+sdc1 => /dev/bcache0 > > On /dev/bcache0, there's a btrfs filesystem with 2 subvolumes, mounted > as / and /home. What's been bothering me are the following entries in > my kernel log: > > [13811.845540] incomplete page write in btrfs with offset 1536 and length 2560 > [13870.326639] incomplete page write in btrfs with offset 3072 and length 1024 > > The offset/length values are always either 1536/2560 or 3072/1024, > they sum up nicely to 4K. There are 607 of those in there as I am > writing this, the machine has been up 18 hours and been under no > particular I/O strain (it's a desktop). > > Trying to fix this, I unattached the cache (still using /dev/bcache0, > but without /dev/sdb3 attached), causing these errors to disappear. As > soon as I re-attached /dev/sdb3 they started again, so I am fairly > sure it's an unfavorable interaction between bcache and btrfs. > > Is this something I should be worried about (they're only emitted with > KERN_INFO?) or just an alignment problem? The underlying HDD is using > 4K-Sectors, while the block_size of bcache seems to be 512, could that > be the issue here? > > I've also encountered incomplete reads and a few csum errors, but I > have not been able to trigger these regularly. I have a feeling that > the error is more likely o be on the bcache end (I've mailed to that > list as well), however any insight into the matter would be much > appreciated. > > Thanks, > > - eb > -- > To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in > the body of a message to [email protected] > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
