Re: XRaid/Cinewave - RAID levels

just FYI

Hi, We just running CineWave HD with Mylex DF4000R 2Gbit Fibre Channel Dual Systems on RAID50. OS 9 Keeps 250MB/sec Read Performance and 180MB/sec Write rate. It's so comfortable.
But OS 10.2.3 and 10.2.4 performance works 90MB/sec Read,120MB/sec Write. So we can't use this systems in CineWave X. Pinnacle's Disc Performance test comes 180MB/sec Read,150MB/sec write. ATTO Express Stripe bench result are 145MB/sec Read performance, but HD 1080/29.97 couldn't play back.
We tested "Charis Mac Anubis RAID Disk Bench" results comes 90MB/sec Read,120MB/sec Write, and that rate correct.
We found interest things with bus analyse system, OS X with ATTO FC3300 create "Ordered Tag Que" command only. It's mean's first LUN recieved command and reply to Host, then OS X can send next command to storage. It's loses data rates. JBOD 2Gbit Fibre Channel Storage could read and write HD contents in OS X, formatted interleave 32K,mode page video,Tag Command Que option.
And OS X controled data packets all 32K....why? Stripe size and cache line size 32K were best performance on OS X.

Last year, we tested Apple's "X serve RAID" with CineWave, 7 Drives RAID0 performance was 170MB/sec Read,140MB/sec Write.

We've expected X serve RAID "RAID 50"

Sincerly yours

Aki Yoshinaga
Japan Data Storage Tech