512B Random Read Testing
The final area that we can compare the tremendous speed of the 9207-8i Mustang against the 9211-8i requires us to use the SanDisk ESS Lightning LS 300S Enterprise Flash Drives in an attempt to saturate the controller with read IOPS.
We configured the four SanDisk SSDs as separate volumes and dialed up the Queue Depth with 512B random 100% read access.
We can observe the 9207-8i topping out much higher than the 9211-8i. The 9207 reaches 633,000 IOPS at top speed compared to the 9211 with 464,000 IOPS. This is an increase of 27%, but actually, the 9207-8i is rated at 700,000 IOPS, which would equate to a 34% increase in IOPS performance.
The SanDisk ESS Lightning's provide us 158,250 IOPS each, which is nearly perfect scaling with their ability to provide up to 160,000 IOPS each.
Here we can see the Lightning's pushing out 632,000 IOPS with an excellent .2021 ms average latency. This low latency is far out of reach with typical SSDs.
The low average latency with very high Queue Depth IOPS requests is what separates the Lightning's from most SSDs. Here we can observe an average latency comparison between the two HBAs, with the 9207-8i enjoying a much lower overall latency.
One aspect of performance that the 9207-8i appears to handle very well is maximum latency. While conducting our 512b random testing we noticed that the maximum latency we were receiving was much higher with the 9211 compared to the 9207.
We conducted the tests several times to assure that the results are accurate and reproducible. While this may be specific to our configuration, we feel that this would be an expected result with the much more efficient PCIe 3.0 specification. The possibility of receiving much better latency alone with existing devices will be enough for many users to make the jump.