On 11/18/2017 12:48 PM, Hans van Kranenburg wrote: > > So, who wants to help? > > 1. Find a test system that you can crash. > 2. Create a test filesystem with some data. > 3. Run with 4.14? (makes the most sense I think) > 4. Continuously feed the data to balance and send everything to /dev/null > 5. Collect stack traces and borken filesystem images.
Ok, what I just did: -# mkfs.btrfs --nodiscard /dev/xvdb -# mount -o noatime /dev/xvdb /btrfs -# cd btrfs/ -# btrfs sub create usr -# rsync -av /usr/ usr/ -# btrfs sub snap -r usr/ usro And then, both at the same time: -# while true; do btrfs send usro/ > /dev/null; date; echo 3 > /proc/sys/vm/drop_caches; done and -# while true; do btrfs balance start --full-balance /btrfs; done After a few minutes we have the first error: [ 1605.484627] BTRFS error (device xvdb): did not find backref in send_root. inode=4260, offset=0, disk_byte=130793844736 found extent=130793844736 Sat Nov 18 13:25:28 CET 2017 At subvol usro/ ERROR: send ioctl failed with -5: Input/output error No big stack trace this time. -- Hans van Kranenburg -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
