TEST SETUP AND METHODOLOGY
In testing the ALLONE Cloud Disk Drive 101, along with all enterprise drives, we focus on long term stability. In doing so, we stress products not only to their maximum rates, but also with workloads suited to enterprise environments.
We use many off-the-shelf tests to determine performance, but we also have specialized tests to explore specific behaviors we encounter. With enterprise drives, you will see that we do not focus on many consumer level use-cases.
Our hope is that we present tangible results that provide relevant information to the buying public.
To specifically measure latency, we use a series of 512b, 4K, and 8K measurements. At each block size, latency is measured for 100% read, 65% read/35% write, and 100% write/0% read mixes.
For average latency, the Cloud Disk Drive 101 gave us some really interesting results, especially the 4KB workload. As you can see, the results for read, write and mixed are almost identical. That is definitely not normal for an SSD, but for a DRAM based product with symmetrical r/w performance, it looks about right. The CDD 101 also excels at small block transfers. As you can see, the 512B performance is one of the highest we have ever seen.
Maximum latency was also excellent. Typically, we see maximums in the 5-20ms range. For all of our tests, we never topped 1ms, which is very impressive.
ADVANCED WRITE TESTING
As we talked about in our Micron P400m SSD Review, SSDs have different performance states. Since the ALLONE Cloud Disk Drive 101 is an enterprise storage device, we will focus on steady state performance. With the following tests, we stressed the drive using random 4KB write workloads across the entire span for at least 24 hours. This is more than enough to achieve steady state. The following graph is showing the latency and IOPS across an 11 hour span.
Here is the deal with the ALLONE Cloud Disk Drive 101; it behaves so unlike an SSD that many of our long-term tests are unnecessary. For a NAND-based SSD, we spend countless hours coaxing them into steady-state. Because the CDD 101 does not have NAND and doesn’t have to worry about P/E cycles, there aren’t different performance states, just steady-state. That is a major benefit of this product is that whether you are 1 second or several days into a run, the performance is identical.
Since we normally run our SSDs with a 4KB workload, the ALLONE does not show its 470,000 IOPS that it can do at 512B. But, what we did see was a very respectable 118,000 IOPS. The performance was also very consistent, with just a few data points in the 120,000 IOPS region.
This was probably one of the easiest storage products to test that we have even had in our labs. It would be reassuring, as a customer, to know that your performance is guaranteed no matter how long your run your test.