The Micron P420m is a great drive that lives up to it sibling, the P320h, in terms of read performance. At 760K IOPS and over 3GB/s, it tore through our tests without breaking much of a sweat. Even with light write workloads, it still managed to produce great results. Micron, as long as the pricing is right, should be able to push this drive into more mainstream, enterprise environments.
Even with the most read-focused drives, we still perform our entire suite of tests, including write testing. If there is any fault with this drive, in terms of our tests, it would be with write performance, specifically sequential write performance. If Micron could have squeezed 1-1.5GB/s sequential writes out of it, they probably could have opened it up to other market segments. That, of course, would not be fair to this drive. This drive is meant as a read caching product, that can handle write operations, but not at the same level as reads.
As we go back and look at our initial challenge, does the P420m really do that much better than a handful of SSDs? Overall, we would say yes, yes it does. We chose the HGST SSD800MM SAS SSDs because they had the best performance we had ever seen in a 2.5″ form factor. In a completely skewed comparison, comparing just write performance, it would still take 2 HGST drives and an HBA to beat the P420m at every test. That configuration would take up more room, use the same amount of power, have less capacity and cost most. Hardly a win.
When you compare the two setups and focus on what the P420m does best, read operations, there is no comparison. Even 4 SSD800MMs could not reach random 4KB read performance of the P420m. Even for sequential reads, it would take at least 3 to match the P420m.
There are plenty of other factors to consider that were not a part of this comparison, but we wanted to know what would happen when you pit the two together.
Taking everything into consideration, the P420m is a great product and we feel it worthy of our Bronze Seal. In considering application specific tasks, this SSD has the ability to pull off some great things!