Plextor M5 Pro (256GB) Review

Random Read/Write Speed

The four corners of SSD performance are as follows: random read, random write, sequential read and sequential write speed. Random accesses are generally small in size, while sequential accesses tend to be larger and thus we have the four Iometer tests we use in all of our reviews. Our first test writes 4KB in a completely random pattern over an 8GB space of the drive to simulate the sort of random access that you'd see on an OS drive (even this is more stressful than a normal desktop user would see).

We perform three concurrent IOs and run the test for 3 minutes. The results reported are in average MB/s over the entire time. We use both standard pseudo randomly generated data for each write as well as fully random data to show you both the maximum and minimum performance offered by SandForce based drives in these tests. The average performance of SF drives will likely be somewhere in between the two values for each drive you see in the graphs. For an understanding of why this matters, read our original SandForce article.

Random read performance is excellent. The M3/Pro already had great random read performance to begin with but M5 Pro takes that one step further. We are looking at figures similar to Vertex 4 here.

At queue depth of 3, the M5 Pro is noticeably faster than its predecessors. The difference is 30MB/s (~18% on average), although Plextor still cannot match the performance of SandForce or Indilinx Everest 2.

Increasing the queue depth to 32 yields great results. Performance has significantly improved since the M3/Pro. The M5 Pro is on par with SandForce and Everest 2 based SSDs here.

Sequential Read/Write Speed

To measure sequential performance we ran a one minute long 128KB sequential test over the entire span of the drive at a queue depth of 1. The results reported are in average MB/s over the entire test length.

Sequential read performance remains unchanged from M3 Pro.

Sequential write is up when compared to M3 Pro, but for some reason, the M3 is still even faster than the M5 Pro.