On 20 September 2017 at 10:47, hw <hw at gc-24.de> wrote: > > Hi, > > xfs is supposed to detect the layout of a md-RAID devices when creating the > file system, but it doesn´t seem to do that: > > > # cat /proc/mdstat > Personalities : [raid1] > md10 : active raid1 sde[1] sdd[0] > 499976512 blocks super 1.2 [2/2] [UU] > bitmap: 0/4 pages [0KB], 65536KB chunk > > > # mkfs.xfs /dev/md10p2 > meta-data=/dev/md10p2 isize=512 agcount=4, agsize=30199892 > blks > = sectsz=512 attr=2, projid32bit=1 > = crc=1 finobt=0, sparse=0 > data = bsize=4096 blocks=120799568, imaxpct=25 > = sunit=0 swidth=0 blks > naming =version 2 bsize=4096 ascii-ci=0 ftype=1 > log =internal log bsize=4096 blocks=58984, version=2 > = sectsz=512 sunit=0 blks, lazy-count=1 > realtime =none extsz=4096 blocks=0, rtextents=0 > > > # mkfs.xfs -f -d su=64m,sw=2 /dev/md10p2 > meta-data=/dev/md10p2 isize=512 agcount=16, agsize=7553024 > blks > = sectsz=512 attr=2, projid32bit=1 > = crc=1 finobt=0, sparse=0 > data = bsize=4096 blocks=120799568, imaxpct=25 > = sunit=16384 swidth=32768 blks > naming =version 2 bsize=4096 ascii-ci=0 ftype=1 > log =internal log bsize=4096 blocks=58984, version=2 > = sectsz=512 sunit=8 blks, lazy-count=1 > realtime =none extsz=4096 blocks=0, rtextents=0 > > > The 64MB chunk size was picked my mdadm automatically. The device is made > from two disks, and xfs either doesn´t figure that out, or it decided to > ignore the layout of the underlying RAID. > > Am I doing something wrong here, or is xfs in Centos somehow different? > Do, or must, we always specify the apporpriate values for su and sw or > did xfs ignore them because what it picked is better? > I don't know enough to answer, but I do have a question.. what were you expecting xfs to do (and what filesystems do that?) Thanks -- Stephen J Smoogen.