8KB Random Read And Write
To read more on our test methodology visit How We Test Enterprise HDDs, which explains how to interpret our charts. We cover 8KB random performance measurements on page two, latency measurements on page five and power measurements on page six.
The 8K random write tests reveal a similar performance profile to the trends we observed with 4K data. The He10 offers the best average performance at 2.5ms, as noted in the latency-over-IOPS subchart. However, the QoS and standard deviation reveal that it suffers more variability under light load (QD1-QD4) than the competing drives. The He10's QoS measurement in the 32QD breakout chart reveals that it offers the best overall profile during mid-range workloads. The performance reduction reappears at high QD measurements for the Seagate 10TB and the HGST He10, but such a heavy workload is going to be a rare occurrence for the target market.
The WD Gold and He8 both appear very similar when we examine the 8K random write scatter chart, which indicates that the similarities during random write workloads appear to extend to pure random read workloads, as well.
The power measurements do not reveal any new information, as the drives all display comparable power and efficiency metrics to the trends we noted during 4K workloads.
Seagate obviously tuned its 10TB drive to provide superior scaling under light random read workloads, and its big performance lead from QD1 to QD64 reappears. The WD Gold and He8 are eerily similar in this workload, as well. The QoS 32QD breakout reveals that there is little differentiation between the drives at QD32 in terms of performance outliers, and the histogram shows the Seagate 10TB and 8TB have more requests fall into the 1-2ms and 4-10ms ranges than the competing devices do. The distribution is the direct result of its leading performance during the QD32 measurement window.
The drives follow a similar pattern to the 4K mixed workload testing, albeit with lower IOPS performance due to the larger file size. The He10 does not appear to cache 8K random write data as well. The He10 does not surpass the Seagate 10TB at the 60/40 threshold as it did during the mixed 4K testing, but the crossover point occurs at the 40/60 mixture. This mixture falls out of the 80/20-60/40 ranges, which are the most common workload distributions. The Seagate 10TB also offers an improved QoS profile during the 8K mixed workloads.