Iometer: 4kB random read/write
We used Iometer to measure the random read speed using 4k data blocks at queue depths of 1 through 32.
With a low queue-depth the Samsung 850 Evo and Pro and the Intel SSD 545s are the fastest. They achieve about 10,000 read-operations per second. At higher queue-depths the SSDs are often close to each other in terms of performance. We only find slow SSDs in the budget segment: the Sandisk SSD Plus, WD Green and Kingstong SSDNow V300 are really slow, among others.
Most 3D NAND SSDs perform slightly worse when writing at a low queue depth, as our test results show. Entirely at the bottom of the graph we find the same budget SSDs that we mentioned before.