Performance in Intel IOMeter FileServer and WebServer Patterns

At first let’s check the controller performance in the file-server storage subsystem:

Let’s build a graph showing the dependence of the arrays speeds on the request queue depth:

RAID 0 arrays show excellent performance scalability depending on the number of hard drives in the array, even when the queue is 64 requests long, and the performance of RAID 0 array of three and four hard disk drives grows slower than expected. The read speed from RAID 1 array is always as high as the read speed from a single hard drive, and the performance of RAID 10 is equal to that of 2-drive RAID 0. Keeping in mind that the FileServer pattern has only 20% of writes, we dare suppose that the SiI3124 controller never uses any reading optimizations for the mirrored arrays.

For a better comparison of different RAID arrays performance we will use our traditional rating system. Provided all workloads are considered equally probable, we will calculate the general performance rating index as the average performance during requests processing under all types of workload.

As we see, the performance rating appeared pretty expected. RAID 0 arrays lined up according to the number of hard disk drives in them. The mirrored arrays, RAID 1 and RAID 10, are falling a little bit behind the single HDD and a 2-drive RAID 0 array respectively.