4k Random Read/Write
Each level tested includes 300 data points (five minutes of one second reports) to illustrate performance variability. The line for each queue depth 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 HGST Ultrastar He6 averages 204 IOPS at QD256, while the 7K4000 delivers 215 IOPS.
Both drives deliver consistent performance and the best performance efficiency at QD64.
The He6 provides peak performance at QD128 with an average of 196 IOPS, and the 7K4000 peaks at QD64 with 206 IOPS.
The He6 and 7K4000 both provide optimal latency-to-IOPS performance at QD64.
Our write percentage testing illustrates the varying performance of each solution with mixed workloads. The 100 percent column to the right is a pure write workload of the 4k file size, and 0 percent represents a pure 4k read workload.
The He6 falls neatly below the speed of the 7K4000 and exhibits the same preference for read activity.
We record power consumption measurements during our test run at QD256. The He6 averages 7.22 watts, and the 7K4000 averages 8.67 watts during the measurement window. This falls in line with the expected power reduction advantages of the He6.
We generate IOPS-to-Watts measurements from data recorded during the test period. The He6 provides 34 IOPS-per-Watt in both workloads, and the 7K4000 measures 30 IOPS-per-Watt. The primary power advantage of the He6 is in Watts-per-TB measurements and idle power consumption. These performance-based efficiency enhancements are also an encouraging sign.