4K Random Read/Write
Each QD for every parameter tested includes 300 data points (five minutes of one second reports) to illustrate the degree of performance variability. The line for each QD represents the average speed reported during the five-minute interval.
4K random speed measurements are an important metric when comparing drive performance, as the hardest type of file access for any storage solution to master is small-file random. One of the most sought-after performance specifications, 4K random performance is a heavily marketed figure.
The WD Re averages 178 IOPS, while the HGST Ultrastar 7k4000 leads the heavy 4K read workload with an average of 216 IOPS at QD256.
The WD Re averages 220 IOPS at QD256 leading the field, while the HGST Ultrastar 7K4000 averages 211 IOPS. The Toshiba MG03ACA400 averages 199 IOPS in comparison to the Seagate V.6 with 205 IOPS at QD256 in our 4K write testing.
Our write percentage testing illustrates the varying performance of each solution with mixed workloads. The 100% column to the right is a pure write workload of the 4K file size, and 0% represents a pure 4K read workload.
The WD Re provides middling performance in comparison to other 7,200 RPM HDDs with its mixed read/write workload performance.
The WD Re provides the best consistency in this test, with the vast majority of I/O's (99.69%) occurring at 100-200ms, and the remaining .31% at 200-400ms. While the 7K4000 has I/O's fall into the lower latency ranges, these are counterbalanced by some operations that take significantly longer than the WD Re.
We record the power consumption measurements during our test run at QD256. The WD Re pulls 9.78 Watts during the measurement window, the highest average among the test pool.
IOPS to Watts measurements are generated from data recorded during our test. The WD Re delivers an average of 26.75 IOPS per Watt for 4K random writes, and 21 IOPS per Watt for 4K random read access. The higher write performance of the WD Re in pure write workloads helps it win the write IOPS to Watts test.