Hello folks, On a running Ceph cluster using XFS for the OSD's, is it safe to defrag the OSD devices while the system is live?
I did a quick check of one device: xfs_db -c frag -r /dev/sdd actual 637596, ideal 144935, fragmentation factor 77.27% I've only been running on these particular machines for a couple of weeks. I am thinking of putting in a cron task that defrags disks every week or as needed (on a rolling schedule). While I'm talking about XFS... I know that RBD's use a default object size of 4MB. I've stuck with that so far.. Would it be beneficial to mount XFS with -o allocsize=4M ? What is the object size that gets used for non-RBD cases -- i.e. just dumping objects into data pool? Thanks, - Travis -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
