we have a NFS sitting on top of XFS and drbd which delivers us a horrible performance (about 1MB/s read / write as shown in iostat/iotop) the xfs volume properties are:
meta-data=/dev/drbd0 isize=256 agcount=4, agsize=52427198 blks = sectsz=512 attr=2 data = bsize=4096 blocks=209708791, imaxpct=25 = sunit=0 swidth=0 blks naming =version 2 bsize=4096 ascii-ci=0 log =internal bsize=4096 blocks=16384, version=2 = sectsz=512 sunit=0 blks, lazy-count=1 realtime =none extsz=4096 blocks=0, rtextents=0
and we have a Dell Box with an SAS1068E Controller and 2 WD 1TB Disks The volume is currently mounted with the properties:
The filesystem contains tons of small files all about 50-100k in size, they are spread around in the directory tree.
We tried playing around with ReadAhead Values (currently disabled) and the xfs mount options but nothing seemed successful so far.
We noticed in the iotop that kdmflush is the process that causes the iowait Any suggestions to improve the Performance of this Setup?