Lustre 2.4.2 performance tests: ZFS vs ext4 backends.

The fastest mysql performance I have seen on RAID10 with 24 SASx4TB disks.
Before testing dd on both was bringing almost 2.5GB/s:
seq 1..8 | xargs -I{} echo "dd if=/dev/zero of=/data/test.{} bs=4M count=1000&"| sh

Next I was testing with Lustre 2.4.2 MDT:
1)ZFS 0.6.2 CentOS6.5
RAID10-ZFS(R0)
mds:>thrhi=16 dir_count=16 file_count=200000 mds-survey
Mon Dec 23 14:48:36 CET 2013 /usr/bin/mds-survey from test.host
mdt 1 file  200000 dir   16 thr   16 create 9185.17 [   0.00,15999.01] lookup 421928.47 [421928.47,421928.47] md_getattr 392586.40 [392586.40,392586.40] setxattr 56024.07 [25998.10,29999.37] destroy 10387.71 [   0.00,15999.41]
done!

2) RAID10-ldiskfs
mds:> thrhi=16 dir_count=16 file_count=200000 mds-survey
Mon Dec 23 15:06:46 CET 2013 /usr/bin/mds-survey from test.host
mdt 1 file  200000 dir   16 thr   16 create 126533.11 [126533.11,126533.11] lookup 1129547.84 [1129547.84,1129547.84] md_getattr 776042.03 [776042.03,776042.03] setxattr 115977.53 [115977.53,115977.53] destroy 156916.53 [156916.53,156916.53]
done!

The result is: zfs is slower than ldiskfs. In some operations it is about 10 times slower than ext4.

This can be that zfs was running on hardware raid 10. Maybe with HBA it will bring more performance.