4K Random Read/Write
We precondition the KingFast F3 Plus Series SSD with 50% compressible data for 18,000 seconds, or five hours, receiving reports on several parameters of workload performance every second. We then plot this data to illustrate the drives' descent into steady state. Please refer to the previous page for a note on data compressibility.
This chart consists of 36,000 data points. This is a dual-axis chart with the IOPS on the left and the latency on the right. The teal dots signify IOPS during the test, and the dark blue dots are latency measurements during the test period. We plot latency data in a logarithmic scale to bring it into comparison range. The lines through the data scatter are the average during the test. This type of testing presents standard deviation and maximum/minimum I/O in a visual manner.
Note that the IOPS and Latency figures are nearly mirror images of each other. This illustrates the point that high-granularity testing can give our readers a good feel for the latency distribution by viewing IOPS at one-second intervals. This should be in mind when viewing our test results.
We provide histograms for further latency granularity below. This downward slope of performance happens very few times in the lifetime of the device, typically during the first few hours of use, and we present the precondition results only to confirm steady state convergence.
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 KingFast F3 Plus averages 55,348 IOPS with a 4K random workload at QD256. The SuperSSpeed S301 falls into such a close race with the F3 Plus that the results overlap each other. The Optimus, used as an MLC comparison, rises above 90,000 IOPS.
Garbage collection routines are more pronounced in heavy write workloads. This leads to more variability in performance. Both LSI SandForce powered SSD's exhibit variability during the 4K write testing. This is due to the compression engine working furiously to compress the data as much as possible in the background. We are using 50% compressible data in all of our tests, and more compressible workloads experience significantly less variability. The KingFast averages 51,390 IOPS during the QD 256 test measurement window.
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.
Both the F3 Plus and the S301 exhibit very similar performance, and great performance with a heavy write workload.
The F3 Plus and S3901 run neck and neck in the latency department, with the S301 delivering slightly more IOPS at the higher range. The F3 Plus provides 78% of I/O in the 4-6ms range, and 18% in the 6-8ms range.
We record the power consumption measurements during our precondition run. We calculate the stated average results during the last five minutes of the test, after the device has settled into steady state.
The real differentiators begin to show with our power consumption and efficiency tests. The F3 Plus delivers much lower wattage than the other SSD's, pulling an average of 3.5 Watts during the preconditioning period.
IOPS to Watts measurements are generated from data recorded during our precondition run, and the stated average is from the last five minutes of the test. The F3 Plus delivers an outstanding 15,889 IOPS per Watt in this test, significantly ahead of the S301 and Optimus.