On 7/13/13 7:11 PM, aurfalien wrote: > Hello again, > > I have a Raid 6 x16 disk array with 128k stripe size and a 512 byte block size. > > So I do; > > mkfs.xfs -f -l size=512m -d su=128k,sw=14 /dev/mapper/vg_doofus_data-lv_data > > And I get; > > meta-data=/dev/mapper/vg_doofus_data-lv_data isize=256 agcount=32, agsize=209428640 blks > = sectsz=512 attr=2, projid32bit=0 > data = bsize=4096 blocks=6701716480, imaxpct=5 > = sunit=32 swidth=448 blks > naming =version 2 bsize=4096 ascii-ci=0 > log =internal log bsize=4096 blocks=131072, version=2 > = sectsz=512 sunit=32 blks, lazy-count=1 > realtime =none extsz=4096 blocks=0, rtextents=0 > > > All is fine but I was recently made aware of tweaking agsize. Made aware by what? For what reason? > So I would like to mess around and iozone any diffs between the above > agcount of 32 and whatever agcount changes I may do. Unless iozone is your machine's normal workload, that will probably prove to be uninteresting. > I didn't see any mention of agsize/agcount on the XFS FAQ and would > like to know, based on the above, why does XFS think I have 32 > allocation groups with the corresponding size? It doesn't think so, it _knows_ so, because it made them itself. ;) > And are these optimal > numbers? How high is up? Here's the appropriate faq entry: http://xfs.org/index.php/XFS_FAQ#Q:_I_want_to_tune_my_XFS_filesystems_for_.3Csomething.3E -Eric > Thanks in advance, > > - aurf > > _______________________________________________ > xfs mailing list > xfs@xxxxxxxxxxx > http://oss.sgi.com/mailman/listinfo/xfs > _______________________________________________ xfs mailing list xfs@xxxxxxxxxxx http://oss.sgi.com/mailman/listinfo/xfs
