I have waited a long time for the day when an alternative to SCSI RAID cards finally becomes available and can match or defeat the performance of SCSI RAID. I just finished reading the article/review of the new SATA RAID cards and was pretty excited, but there was one huge factor that was left out, and seems to be left out from most of the discussions I see about IDE/SATA vs. SCSI: CPU utilization.
I am a UNIX Systems Engineer for a hosting company and we pay an incredible amount for the I/O subsystem in our servers. Once the 73GB U320 SCSI drives are added in, plus the $400 SCSI RAID card, it makes up about 1/3 to 1/2 the price of the server. But, the performance, as far as I've seen so far, is unparalleled. And with dozens of virtual private servers all running on the same machine, each containing perhaps hundreds of processes, the I/O subsystem must be nothing short of blazing. One of the most important aspects of this is CPU utilization. It would simply be not feasible to manage hosting in the way that we do if CPU utilization from I/O was not minimal.
Herein lies the problem with IDE that I've seen so far. The transfer rates have been competitive with SCSI for some time, but the CPU utilization is monstrious comparatively. Even with a dedicated controller card from 3Ware, the CPU utilization will bring the box to its knees on heavy access.
So, my question to the people on the forum is: Does anyone have any statistical analysis of the CPU utilization of these new SATA cards, or perhaps know of a review on some other site that has such information? I'd rather just read articles on THG. I wonder if they would be interested in amending this information to their article?
I am a UNIX Systems Engineer for a hosting company and we pay an incredible amount for the I/O subsystem in our servers. Once the 73GB U320 SCSI drives are added in, plus the $400 SCSI RAID card, it makes up about 1/3 to 1/2 the price of the server. But, the performance, as far as I've seen so far, is unparalleled. And with dozens of virtual private servers all running on the same machine, each containing perhaps hundreds of processes, the I/O subsystem must be nothing short of blazing. One of the most important aspects of this is CPU utilization. It would simply be not feasible to manage hosting in the way that we do if CPU utilization from I/O was not minimal.
Herein lies the problem with IDE that I've seen so far. The transfer rates have been competitive with SCSI for some time, but the CPU utilization is monstrious comparatively. Even with a dedicated controller card from 3Ware, the CPU utilization will bring the box to its knees on heavy access.
So, my question to the people on the forum is: Does anyone have any statistical analysis of the CPU utilization of these new SATA cards, or perhaps know of a review on some other site that has such information? I'd rather just read articles on THG. I wonder if they would be interested in amending this information to their article?