Kamaraju S Kusumanchi wrote:
Actually, this is where the problem originated. We looked at the part numbers of a hard drive in a cluster and ordered the parts online. But to our dismay, we found that they have different rpm even though their part numbers are same. I don't think this is a reliable way of finding out the rpm. We also tried "hdparm -t /dev/sdb" to find out about the drive speeds. But that gives the end result and not the actual hard drive rpm.
Try comparing the read/write speeds of the drive with those of a known drive. It might be give you a reasonable guess of the RPM.