Hi All,
I've just started caring for a dual Opteron machine. It has a 3Ware 9500S-12 RAID controller, a Tyan S2882G3NR motherboard, 10 IBM 400GB disk drives, and a 650 watt power supply.
It has been behaving itself quite nicely until recently. The poor behavior started when I upgraded the OS from CentOS 4.1 (32 bit) to Centos 4.1 (x86_64). When running in uniprocessor mode, the system appears to work properly. However, when running in SMP mode I get a lot of SCSI disk errors in /var/log/messages. I've upgraded the 3w_9xxx driver and firmware, but no joy (actually, I did get some joy out of recompiling the kernel. Its been several years since I last compiled a kernel and the process has changed for the better).
I've been in contact with 3Ware. From the error logs I supplied to them, it looks like the issue is an insufficient power supply. Their rule of thumb is 300W for the motherboard and 35 W for each disk drive. That means that I would need (at a theoretical minimum) a 650 W power supply - which I have.
I only notice the problem in SMP mode, not in uniprocessor mode. That suggests to me that (1) I have a boarderline-sufficient power supply that can support one but not two CPUs or (2) there is a problem with the combination of Opteron/3Ware 9500S-12 hardware and the x86_64 SMP kernel. I suppose there are even worse possibilities, but I'd rather not think about those right now.
What do you think?
Does anyone have any experience with this sort of hardware on x86_64 kernels?
Does the 3w_9xxx driver work well on a x86_64 machine?
Does anyone have a suggestion as to what capacity power supply I should have?
Thank you, Evan