Results: Sequential Read And Write Performance
Fantastic sequential read and write performance is a trademark of modern SSDs. To measure it, we use incompressible data over a 16 GB LBA space, and then test at queue depths from one to 16. We're reporting these numbers in binary (where 1 KB equals 1024) instead of decimal numbers (where 1 KB is 1000 bytes). When necessary, we also limit the scale of the chart to enhance readability.
128 KB Sequential Read
Using the popular Plextor M5 Pro as a comparison point gives us the opportunity to examine two otherwise-similar drives attached a couple of different ways. In the chart above, the biggest difference isn't controller or firmware, but rather the circumvention of SATA 6Gb/s' speed barrier. Both drives come armed with the same number of dies, and employ the same 19 nm Type A Toggle-mode DDR flash.
Anywhere above a queue depth of one, the PCIe-based M6e is significantly quicker than the M5 Pro, ending up more than 200 MB/s faster than the SATA-bound SSD. It's not that we haven't seen performance like this before. But it always makes me happy to see it again.
128 KB Sequential Write
The PCIe-attached M6e strikes again, besting the M5 Pro to the tune of 100+ MB/s. And the 256 GB model isn't even the fastest M6e. Plextor's 512 GB model should add even more sequential throughput.
Here's a breakdown of the maximum observed 128 KB sequential read and write performance with Iometer:
Of course, the only other truly comparable drive is SanDisk's A110, which uses the same M.2 form factor. In fact, both drives pack the same Marvell 88SS9183 heater and 19 nm Toggle-mode flash, backed by custom firmware. But unlike the A110, Plextor's drive is something you can buy right now, while the A110 remains OEM-only.
