128K Sequential Read/Write
The 128K sequential speeds reflect the maximum sequential throughput of the SSD using a realistic file size encountered in an enterprise scenario.
The HGST SSD800MM has two performance modes. The efficiency mode is tuned for efficiency and draws 9-Watts of power, while the high performance mode draws 11-Watts and delivers maximum performance. We tested extensively with the different settings, and found the only performance benefit to be in sequential write situations. We included these 9-Watts results along with the 11-Watts tests, as the sequential testing was the only area we noticed drastically different behavior. All other testing is with the 11-Watt setting.
The difference between the two power modes does not show up in this workload, but below in the write testing, we will note a significant difference. The HGST SSD800MM averages an amazing 1,042 MB/s in sequential read speed, well above the competing SSDs. The Toshiba PX02SMF080 averages 823MB/s at QD256 in comparison to the Optimus with 586MB/s at QD256.
In our sequential write testing, we observe higher performance from the HGST SSD800MM in the 11-Watt performance mode. The 9-Watt setting delivers an average of 635 MB/s, while the 11-Watt setting bumps that up to 700 MB/s. A jump of 65 MB/s brings the HGST SSD800MM into the same sequential write performance envelope of the SMART Optimus.
The HGST SSD800MM has both 9-Watt and 11-Watt results included in the graph, but we can barely note a trace of the 11-Watt results. This is due to the nearly imperceptible difference in performance across the entire range of mixed read/write percentages. The extent of the difference lies in the 100% 128K sequential write workload. In mixed workloads, the higher power level does not provide any benefits.
The HGST Ultrastar SSD800MM provides an extremely tight performance range, with 1,442,399 I/Os (94.87%) at 40-60ms, and 77,863 I/Os (5.12%) at 60-80ms.
The HGST SSD800MM averages 9.53 Watts in the 11-Watt performance mode. With the 800GB capacity versions of the HGST SSD800MM featuring two PCB's we surmise that the extra NAND and PCB for the higher capacity 800GB model will bring this power draw into the 11 Watt range.
The 9-Watt performance setting actually consumes an average of 7.9 Watts during our testing.
The HGST provides an average of 73 MB/s per Watt in the 11-Watt performance mode, and the 9-Watt mode delivers a more economical 88 MB/s per Watt.