Samsung SM951 NVMe M.2 PCIe SSD Review

IOMeter 4KB Random Performance

Our 4KB random performance test is conducted in the same manner as our sequential tests, but once the drive is conditioned we run our saved random test profile that runs our 4KB test for two minutes without any idle time in between the tests. The queue depth is set to 32 on four workers and the test is begun. To get the benefits from NVMe based drives you must use multiple CPU queues and this is why we are now using four workers for this IOMeter test.

IOPS is the main thing we are looking at in this test scenario and the Samsung SM951 NVMe series is rated as having up to 300,000 IOPS for 4K Random Reads and for some reason Samsung doesn’t mention the 4K Random Write performance in their press release. Our IOMeter testing found that we were getting 298,300 IOPS Read and 33,000 IOPS Write. We are confident that our testing was done properly since we hit the 4KB Random Read number on the head, but the write number was lower than we expected. Could this be why Samsung didn’t mention it in the press release?

When it comes to MBps you are looking at 1222MB/s on the 4KB Random Reads and 134MB/s on the 4KB Random writes.

The response times on the Samsung SM951 were below 0.5ms for the 4KB random read testing, but was nearly 4ms on the random write operations.