I need a little help when trying to calulate available IOPS in a raid array. I have been looking at wmarrow's calculator (http://www.wmarow.com/strcalc/
) and I am a little lost when it gets to read cache hit ratio and write cache hit ratio. With four 7200rpm sata 3.0 drives in a raid 10 I get between 227 and 23000 IOPS (at 70%/30% read/write ratio) depending on how I manipulate these two fields. How should I properly calculate these two fields?
I realize that in production I would want fast 15K SAS drives, and as many as possible, but this is for a lab environment and I do not have the budget for SAS drives. Just need to get an estimate of how many iops I will have to deal with so I don't overtax the box. It will be running vSphere Hypervisor 4.1.