Suppose you setup 8 drives in a RAID 10 configuration using 2.5" drives using 500GB capacity each (total 2TB with RAID10 config 1TB useable).
The controller (assume a typical 3ware SATA controller) is housed within a NAS setup that will use iSCSI and LVM cluster for data management/delivery over a 2GB dual nic bonded uplink.
The specs for latency on both 7200 and 5400 RPM drives are very similar. Average Latency: 5.5 ms
In terms of type of data access, consider it for server use for virtual servers hosting.
The output/throughput is being run through the RAID to give a combined total of X number of MB/s that can be delivered, so I tend to think that the RPM speed will not provide a big performance hit with the combined output of the disks.
If you are running with a RAID 10 array like this, would you probably get similar performance from both a 7200 RPM set of drives and a 5400 RPM set of drives?
Best Answer
Spindle speed does not matter, for writes, if your RAID controller "assume a typical 3ware SATA controller" is assumed to be one with a fair amount of RAM.
High end 3Ware controllers actually have a setting to flush the write back cache before returning
http://www.3ware.com/support/UserDocs/7.5.3_UG.pdf
in addition to HBA ram, your hard disk also has a write cache.
Spindle speed is more of a factor for reads and with a RAID-1 or RAID-10, the performance will benefit from load balanced reads. Thus, I doubt you'll see much difference between two 5400 vs. two 7200s in this situation.