On Tue, Feb 07, 2012 at 05:41:10PM +0000, Tom Crane wrote: > Eric Sandeen wrote: > >On 2/6/12 5:19 AM, Tom Crane wrote: > >>Eric Sandeen wrote: > > > >... > > > >>>Newer tools are fine to use on older filesystems, there should be no > >>Good! > >> > >>>issue there. > >>> > >>>running fsr can cause an awful lot of IO, and a lot of file reorganization. > >>>(meaning, they will get moved to new locations on disk, etc). > >>> > >>>How bad is it, really? How did you arrive at the 40% number? Unless > >>xfs_db -c frag -r <block device> > > > >which does: > > > > answer = (double)(extcount_actual - extcount_ideal) * 100.0 / > > (double)extcount_actual; > > > >If you work it out, if every file was split into only 2 extents, you'd have > >"50%" - and really, that's not bad. 40% is even less bad. > > Here is a list of some of the more fragmented files, produced using, > xfs_db -r /dev/mapper/vg0-lvol0 -c "frag -v" | head -1000000 | sort > -k4,4 -g | tail -100 > > >inode 1323681 actual 12496 ideal 2 > >inode 1324463 actual 12633 ideal 2 ..... > >inode 1320625 actual 20579 ideal 2 > >inode 1335016 actual 22701 ideal 2 > >inode 753185 actual 33483 ideal 2 > >inode 64515 actual 37764 ideal 2 > >inode 76068 actual 41394 ideal 2 > >inode 76069 actual 65898 ideal 2 Ok, so that looks like you have a fragmentation problem here. What is the workload that is generating these files? Cheers, Dave. -- Dave Chinner david@xxxxxxxxxxxxx _______________________________________________ xfs mailing list xfs@xxxxxxxxxxx http://oss.sgi.com/mailman/listinfo/xfs
