HD Tach craziness

[alternate]

The image below shows HD Tach results for two SATA2 WD RE hard drives in RAID 0. It's a bit odd that the burst rate is 1300 MB/s plus, isn't it? Two 15k scsi drives configured in RAID 0 have this between 220 and 320 MB/s. More recently, with an LSI 320-1 controller I got a shocking 113 or so MB/s for burst rate; the read rate is still about 140 - 160 MB/s for that set-up with any controller.

Anybody know what might be the case with the LSI 320-1? And with the former results with onboard SATA controller on the Gigabyte board?

http://i16.tinypic.com/646q8ld.jpg

[Paul Komski]

It's a bit odd that the burst rate is 1300 MB/s

The only explanation that makes sense to me would be if it was reading a sector from cache and not from the disk surface. I always view such stats with suspicion at the best of times.