read/write benchmarking: UFS2 vs ZFS vs EXT3 vs ZFS RAIDZ vs Linux MDRAID

[Andrew Snow]

 > Contiguous Write Performance:
 > 
http://virtual.tehinterweb.net/livejournal/2009-06-22_zfs_diskperf/zfs-diskperf-contig-write.png


What confuses me about these results is that the '5 disk' performance 
was barely higher than the 'single disk' performance.  All figures are 
also lower than I get from a single modern SATA disk.

My own testing with dd from /dev/zero with FreeBSD ZFS an Intel ICH10 
chipset motherboard with Core2duo 2.66ghz showed RAIDZ performance 
scaling linearly with number of disks:


What               Write   Read
--------------------------------
7 disk RAIDZ2      220     305
6 disk RAIDZ2      173     260
5 disk RAIDZ2      120     213


Only the on-board controllers were used, with Seagate disks of around 
250GB capacity.  System had 8GB RAM.  These results are so different in 
absolute terms to your results that I don't know how to interpret your set.


- Andrew