On Wed, Jun 06, 2012 at 12:06:36PM +0200, Richard Ems wrote: > On 06/06/2012 01:45 AM, Dave Chinner wrote: > > No surprise if you have a large filesystem and the filesystem is > > changing while xfs_db is running. xfs_db is not coherent with > > mounted filesytems, and it is not recommended that you use it that > > way.s xfs-db is a debugging tool, not a filesystem state reporting > > tool. > > Ok, thanks, didn't know that. > I would like to monitor the fragmentation value for all my mounted XFS. > I think I read in previous list messages that also other people are > using xfs_db this way. Or is there another way to get the fragmentation > value? No, and what xfs_db reports is mostly useless. You don't have a fragmentation problem unless you are noticing performance problems, and no fragmentation number will ever tell you that.... > I found this segmentation fault error very strange, since I have been > using "echo frag | xfs_db -r" for months already on other big > filesystems - 2 x 17 TB, 1 x 25 TB, 1 x 20 TB - and NEVER got a > segmentation fault. All 4 filessystems are mounted read-write and are in > heavy IO use, nevertheless "echo frag | xfs_db -r" runs as expected (by > me), no one xfs_db run crashed with a segmentation fault at all for > months, running every weekend. > It also ran several times without giving any errors on this 80 TB XFS, > but then started to throw segmentation faults some weeks ago. It's entirely possible it is running out of memory, failing to capture the failure and dereferencing a null pointer.... Cheers, Dave. -- Dave Chinner david@xxxxxxxxxxxxx _______________________________________________ xfs mailing list xfs@xxxxxxxxxxx http://oss.sgi.com/mailman/listinfo/xfs
