Dear all, During a move of some 60GB of data from an ext4 partition to a btrfs partition, both on the same disk, the following happened: - my window manager froze; - the move suspended, i.e., no more data was written to the destination or deleted from the source; - part of top output: (sorry for possible wrapping; sending this from webmail) PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND 13610 root 20 0 0 0 0 D 26 0.0 299:45.87 btrfs-cache-279 1566 root 20 0 0 0 0 S 22 0.0 218:30.86 btrfs-endio-met (there were also a firefox instance and an npviewer.bin process still consuming CPU time, but I guess this was some flash movie happily playing along during the freeze); - those two btrfs processes could not be terminated, not even by kill -9; - "lsof 1566" output (similar for the other process): COMMAND PID USER FD TYPE DEVICE SIZE/OFF NODE NAME btrfs-end 1566 root cwd DIR 8,6 4096 2 / btrfs-end 1566 root rtd DIR 8,6 4096 2 / btrfs-end 1566 root txt unknown /proc/1566/exe After a reboot, I am able to mount the btrfs filesystem, and read data from it, but as soon as I try any write operation (even a simple touch), that command hangs, and there are two btrfs processes hanging around, just as above; dmesg gives lots of "parent transid failed" messages. My kernel is 2.6.36 (with gentoo patches). So, the questions: 1) Is this a known problem? If so, is it fixed in a newer version? In the archive of this list, I read about others with "parent transid failed" errors, and a recovery operation (suggested by Chris Mason), using btrfs-select-super <http://www.spinics.net/lists/linux-btrfs/msg07572.html>. 2) Should I try this procedure to fix my filesystem? Is there any debug information I should collect first? (I can recreate the two "spinning" processes by rebooting and writing to the filesystem.) I am saddened by this failure, as this data move was actually part of an operation to switch over to btrfs completely, after using it without problems for quite a while. Thanks for any help. Keep up the good work. Regards, Arie Peterson -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html