I got a faulty memory module a while ago, and it ran for a while, corrupting a number of filesystems on that server. Most of the corruption is long gone, as the filesystems (ceph osds) were reconstructed, but I tried really hard to avoid having to rebuild one 4TB filesystem from scratch, since it was still fully operational. I failed, but in the process, I ran into and fixed two btrfs check --repair bugs. I gave up when removing an old snapshot caused the delayed refs processing to abort because it couldn't find a ref to delete, whereas btrfs check --repair completed successfully without fixing anything. Mounting the apparently-clean filesystem would still run into the same delayed refs error, but trying to map the logical extent back to a file produced an error. Since it was far too big to preserve, even in metadata only, I didn't, and proceeded to mkfs.btrfs right away. Here are the patches. -- Alexandre Oliva, freedom fighter http://FSFLA.org/~lxoliva/ You must be the change you wish to see in the world. -- Gandhi Be Free! -- http://FSFLA.org/ FSF Latin America board member Free Software Evangelist|Red Hat Brasil GNU Toolchain Engineer