4K Random Read/Write
We precondition the CloudSpeed 1000E 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.
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 light green dots signify IOPS during the test, and the olive green dots are latency measurements during the test period. We place 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 below.
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 CloudSpeed 1000E averages 67,919 IOPS with a 4K random read workload at QD256. This falls in right below the Samsung SM843, which is impressive. The Samsung SM843 has long held the top read speed in our testing, but the CloudSpeed gives it a run for the money in this test. We also note the massive speed increase compared to the previous generation CloudSpeed 500.
Garbage collection routines are more pronounced in heavy write workloads. This leads to more variability in performance. The CloudSpeed 1000E exhibits a very tight performance range at the middle of the chart, averaging a whopping 28,333 IOPS in steady state. This is well over the SMART's conservative rating of 25,000 IOPS.
The CloudSpeed 500 featured significant variability in this test and an average speed that was below that of the 1000E version. The significant increase in performance consistency for the 1000E is very encouraging, and the DC S3500 and the SM843 fall behind with nearly half the write speed of the 1000E.
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.
The CloudSpeed 1000E cuts through the clutter, exhibiting tight consistent performance that beats the other SSDs. The CloudSpeed 500 has a higher average in the 40-90% range, but significant variability muddies the water.
The CloudSpeed 1000E delivers a very tight latency range reflective of its consistent performance, with 35.4% of I/O's (3,007,151) falling into the 8-10ms range, 28.6% at 10-20ms, and 27.6% at 6-8ms.
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 CloudSpeed 1000E averages 3.31 Watts during the test period. These is the highest power consumption from the test field, but with much higher performance, the efficiency numbers below are more pertinent.
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 CloudSpeed 1000E delivers 6,416 IOPS per Watt while under the 4K write workload. This is a slightly lower than the 500, but the 1000E enjoys a lead over the other competing SSDs.