On Friday 14 of June 2013 08:56:55 Sage Weil wrote: > On Fri, 14 Jun 2013, Karol Jurak wrote: > > I noticed that writing to RBD image using kernel driver while it's > > snapshot is being created causes I/O errors and the filesystem > > (reiserfs) eventually aborts and remounts itself in read-only mode: > > This is definitely a bug; you should be able to create a snapshot at any > time. After a rollback, it should look (to the fs) like a crash or power > cycle. > > How easy is this to reproduce? Does it happen every time? I can reproduce it in the following way: # rbd create -s 10240 test # rbd map test # mkfs -t reiserfs /dev/rbd/rbd/test # mount /dev/rbd/rbd/test /mnt/test # dd if=/dev/zero of=/mnt/test/a bs=1M count=1024 and in another shell while dd is running: # rbd snap create test@snap1 After 2 or 3 seconds dmesg shows I/O errors: [429532.259910] end_request: I/O error, dev rbd1, sector 1384448 [429532.272554] end_request: I/O error, dev rbd1, sector 872 [429532.275556] REISERFS abort (device rbd1): Journal write error in flush_commit_list and dd fails: dd: writing `/mnt/test/a': Cannot allocate memory 590+0 records in 589+0 records out 618225664 bytes (618 MB) copied, 15.8701 s, 39.0 MB/s This happens every time I repeat the test. -- Karol Jurak -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
