Base Product Specifications
The five major measurements of base performance of any Solid State Storage solution are latency, random read/write and sequential read/write speed. These are the most common measurements that are posted by manufacturers to advertise storage performance.
We begin with a measurement of the latency of the device. The industry standard for measurement of latency is 4K Random Access at a Queue Depth (QD) of 1.
Both of the 910s capacities are illustrated here, but the lines overlap at the lower QD so closely that there is virtually hardly any difference between the two. The 800GB model has a latency of .142 and scales up accordingly as we apply higher QD to the devices. The listing of QD4 is actually QD1 of each volume for the 800GB version and QD2 per volume with the 40GB model. At QD1 the 400GB comes in with .140.
4K random read speed measurements are an important metric when comparing drive performance, as the hardest type of file access for any storage solution is small-file random. We test with a five second ramp time to eliminate any burst results. Read speeds are largely unaffected by extra Overprovisioning, so we only include standard results.
The 4K random read speeds indicate solid scaling as we pass up through to the higher QDs. The 800GB tops out at QD256 at 227,247 IOPS, this is well above the rated 180,000 IOPS by over 21%!
The 400GB version peaks at 113,489 IOPS at QD128, also 21% over the rated specification of 90,000. Intel has only advertised Steady State specifications for the 910 and obviously conservatively at that.
This also highlights the nearly perfect scaling that we will see over the course of the benchmarks. The LSISAS2008 PCIe bridge scales exceptionally well with each of the four controllers, so the 400GB results are always nearly half that of the 800GB.
As we move into the random write results we begin to include our 20% Overprovisioning results, indicated as "OP" in our graphs. OP consists of leaving 20% of the drive unformatted. By increasing the amount of available spare area, the SSD can perform at higher write speeds. This represents an optional performance boost for users at the cost of some capacity.
The 800GB results with standard Steady State peak at 85,768 IOPS at QD32. This is 13% higher than the rated 75,000. The OP result reaches 100,342 IOPS at QD32. Reaching over 100,000 IOPS in Steady State 4k write is certainly nothing to sneeze out and one of the most impressive results in this entire evaluation.
The 400GB plateaus at QD32 with 42,971 IOPS, 12% higher than the rated 38,000. The OP results reach 52,421 IOPS at QD16.
The 128K sequential read speeds reflect the maximum sequential throughput of the SSD using a realistic file size that will actually be encountered in an enterprise scenario.
The 800GB scores at 1956MB/s, right below the advertised 2.0GB/s. We can observe similar results with the 400GB, coming in at 973MB/s, a tad below the rated 1GB/s.
The 128K Sequential Write speeds of the 800GB top out at 1480MB/s, right below the rated 1.5GB/s using the Maximum Performance mode. The default power mode hits 1GB/s with sequential write access. The 400GB reaches 745MB/s, right at the rated spec of .75GB/s.