A 24TB volume on a Mac Pro
This is by far the largest RAID I’ve ever created: 24TB as twelve (12) 2TB Hitachi 7K2000 drives. Not an idle exercise, my goal was extreme testing of my IntegrityChecker program, as well as to beat up on two of the FirmTek SeriTek/2ME4-E eSATA cards. It’s looking like the SeriTek/2ME4-E will be my new recommended eSATA card: it has run extremely well and it works perfectly booting into the 64-bit Snow Leopard kernel.
Unfortunately, while this RAID 0 stripe can achieve over 1400MB/sec speed, the quad-core Mac Pro Nehalem 2.66GHz maxes out its CPUs at about 1125MB/sec (using IntegrityChecker). Of course, that’s of purely academic interest, since there’s nothing you can do that requires this kind of disk speed. Well, perhaps 4K uncompressed video.
Four of the 2TB drives are in the Mac Pro internal drive bays, and the other eight are in two FirmTek SeriTek/2eEN4 enclosures hooked up to two SeriTek/2ME4-E eSATA cards.
disktester run-area-test -c 128M -t 4G -i 3 h12
...
--- Averages for "h12" (4GB/128MB, 3 iterations) ---
Area (21.8TB) Write MB/sec Read MB/sec
0% 1475 1451
10% 1347 1381
20% 1378 1359
30% 1219 1290
40% 1249 1211
50% 1231 1200
60% 1181 1135
70% 1096 1038
80% 970 954
90% 905 855
100% 756 716
Average write speed across the volume: 1164MB/sec
Average read speed across the volume: 1145MB/sec