Hi there.. I can't tell you the best controller, but I can share my
experiences so far with the Megaraid cards..
I have a 3 Channel LVD controller.. my 5x18.2Gb Disk RAID 5 array is spread
over the three channels to avoid bottlenecks..(2 disks on channels 0,1 and 1
disk on channel 2)
I have optimised the file-systems and controller preferences for
speed...(i.e. Dynamic Read, WriteBack, 64K block)
I still only get 6Mb Per second for sequential writes (ignoring buffering)..
(tested with iozone, tiotest & bonnie)
With buffering, we see supposed throughput of over 200Mbsec on files less
than 128Mb
Read performance is excellent!
Most importantly though, our Web Application (heavy random type IO - MySQL
database) runs real fast.. I'm doing some stress tests today with SSL
enabled to see how it copes under pressure.
HTH
Matthew clark.
