Samsung 750 EVO 120 & 250GB SATA III SSDs Review (Page 7)

Iometer – Maximum IOPS

Version and / or Patch Used: Iometer 2014

We use Iometer to measure high queue depth performance. (No Partition)

Max IOPS Read

Max IOPS Write

We are not sure how Samsung got 88K write IOPS for their specifications because while both drives start out at 89,000 IOPS with our test configuration, after 10 seconds, they both drop, all the way down to 50K for the 120GB and 66K for the 250GB model. This just goes to show that IOPS at QD32 don't matter much in terms of real-world performance. We need to look no further than the BP5e to prove this point. The BP5e has stellar maximum IOPS, but it cannot deliver near the moderate workload performance of the 750 EVO.

Iometer – Disk Response

Version and / or Patch Used: Iometer 2014

We use Iometer to measure disk response times. Disk response times are measured at an industry accepted standard of 4K QD1 for both write and read. Each test runs twice for 30 seconds consecutively, with a 5-second ramp-up before each test. We partition the drive/array as a secondary device for this testing.

Avg. Write Response

Avg. Read Response

The 850 EVO generates the best read/write response times. The 750's are both hot on its heels, though. If we focus on read response times, Samsung's advantage over the competition is glaring. The EVO's read latency at QD1 is 45-55% better than the competing drives that comprise our test pool.

DiskBench - Directory Copy

Version and / or Patch Used: 2.6.2.0

We use DiskBench to time a 28.6GB block (9,882 files in 1,247 folders) composed primarily of incompressible sequential and random data as it's transferred from our DC P3700 PCIe NVME SSD to our test drive. We then read from a 6GB zip file that's part of our 28.6GB data block to determine the test drives read transfer rate. Our system is restarted prior to the read test to clear any cached data, ensuring an accurate test result.

Write Transfer Rate

Read Transfer Rate

So far there has been very little to distinguish the 850 EVO as a more powerful SSD than the 750 EVO. Our transfer testing, however, clearly display's the strength of Samsung's V-NAND technology and why it is superior to planar on all fronts with the exception of cost per gigabyte.

The BP5e is able to deliver significantly better sustained write transfer rates than the 120GB 750 EVO, but keep in mind that this is accomplished with 4x the capacity. However, at the 250GB capacity point, the 750 EVO is able to beat up on the BP5e with a 51 MB/s better sustained write transfer rate.