I'v had over a week now to test with the HighPoint RocketRaid, a low cost RAID controller supporting eight SAS 2.0 drives. I was initially surprised by the small size and cost of $250. The last controller I purchased was an Areca ARC-1230, a 12 port SATA 2.0 RAID controller that costed $780.
Of course, with all things cheap, there's usually a good reason. For starters, there is no cache on the controller, good and bad.This means you can skip the battery backup module and save some money, but also means lowered performance. However, since this is for a low power iSCSI setup, choosing fileio and having a UPS backup will solve this issue.
Since my SAS drives have not arrived yet, I've tested with some older 250GB SATA drives, three of them in RAID5. This produces approximately 120MBps in read tests. While building the array, I noticed that this is one of the slowest rebuilds I've ever seen in my life...slower than software RAID rebuild!!! Six hours to build a 3x250GB setup is just unacceptable!!! On the areca, a 10x1TB RAID6 initial build takes about six hours in comparison!
During the initial build, the read rates will show 25MBps. This is because the rebuild rate is set to normal. Setting it to low will yeild about 40MBps, still quite depressing. The Areca controller will put out between 150-180MBps with 4x1TB drives when one of them fails and is rebuilding in comparison.
I'm also testing 4x500GB Seagate Momentus 7200.4 drives until the 2.5" Constellation SAS comes in. Again, very slow rebuild time. 11 hours for this setup!!! I'm afraid to see the rebuild time of 1TB+ drives on this controller. Performance during rebuild is the same as before with the older drives. Don't underestimate these momentus drives, they are quite speedy pushing out 97MBps per drive!
Last point. The software on the 2720 is designed to act as a pass through if your drive has a partition table on it. This crashed Opensuse 11.3 x64 instantly when the drive was plugged in and the system will not reboot. Using the RAID console to initialize the drive and add it to the new array solved this problem. So remember, get rid of your partition table before doing a hotswap add with this controller!!!
With that said, you get what you paid for. However, I wanted something low power and didn't need a significant amount of speed like the Areca would provide. The interesting thing here is that the Areca cards have been out for maybe 3 years and is one of their entry level controllers running a 500Mhz processor. Their current top of the line runs not one but two 1.2Ghz processors!!! The onboard NICs are the limiting factor anyway. Below list my current specs:
- Supermicro Motherboard mini-ITX Atom motherboard
- Intel Atom D510 (Dual core 1.66 Ghz w/ HT)
- Kingston 2GB SoDIMM DDR2-800 @ 667Mhz
- Highpoint RocketRaid 2720
- 1 x Seagate Barracuda 7200.8 200GB (OS drive)
- 2 x Seagate Barracuda 7200.9 250GB
- 1 x Western Digital Caviar 250GB
- 4 x Seagate Momentus 7200.4 500GB
- 2 x Intel Gigabit NICs onboard