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@thx0701: You've tested a file with a size of 8MB. This will be cached by the RAID controller and though your results are not comparable.
@Robotbeat: Same to you. You should test with files 2 to 4 times larger than your RAID controller's cache to get meaningful measurement results.
I should not blame others if making the same mistakes.
Now I've used 500MB filesize running 8 times.
(= A total of 4GB filesize which means 4 times the RAID controller's cache)
http://www.familiedohse.de/pictures/...nchmark-01.jpg
Part of the reason I started doing these benchmarks was because I wanted to see how fast the cache was. If you have 100GB of system RAM and a database less than 100GB, then you can basically cache the whole thing. That's a good idea if performance is way more important than data integrity. Also, eventually the failover will support memory-coherent replication, instead of waiting for the destination side to write to disk. So then you will have data integrity AND performance.