For our last benchmark, we have decided to use PCMark 8 Extended Storage Workload in order to determine steady state throughput of the SSD. This software is the longest in our battery of tests and takes just under 18 hours per SSD. As this is a specialized component of PCMark 8 Professional, its final result is void of any colorful graphs or charts typical of the normal online results and deciphering the resulting excel file into an easily understood result takes several more hours.
There are 18 phases of testing throughout the entire run, 8 runs of the Degradation Phase, 5 runs of the Steady State Phase and 5 runs of the Recovery Phase. In each phase, several performance tests are run of 10 different software programs; Adobe After Effects, Illustrator, InDesign, Photoshop Heavy and Photoshop Light, Microsoft Excel, PowerPoint and Word, as well as Battlefield 3 and World of Warcraft to cover the gaming element.
- PRECONDITIONING -The entire SSD is filled twice sequentially with random data of a 128KB file size. The second run accounts for overprovisioning that would have escaped the first;
- DEGRADATION PHASE – The SSD is hit with random writes of between 4KB and 1MB for 10 minutes and then a single pass performance test is done of each application. The cycle is repeated 8 times, and with each time, the duration of random writes increases by 5 minutes;
- STEADY STATE PHASE – The drive is hit with random writes of between 4KB and 1MB for 45 minutes before each application is put through a performance test. This process is repeated 5 times;
- RECOVERY PHASE – The SSD is allowed to idle for 5 minutes before and between performance tests of all applications. This is repeated 5 times which accounts for garbage collection; and
- CLEANUP – The entire SSD is written with zero data at a write size of 128KB
In reading the results, the Degrade and Steady State phases represent heavy workload testing while the recovery phase represents typical consumer light workload testing.
As you can see, performance is recorded in terms of Bandwidth and Latency. Bandwidth (or throughput) represents the total throughput the drive is able to sustain during the tests during each phase. Latency, at least for the purposes of PCMark 8, takes on a different outlook and for this, we will term it ‘Total Storage Latency’. Typically, latency has been addressed as the time it takes for a command to be executed, or rather, the time from when the last command completed to the time that the next command started. This is shown below as ‘Average Latency’.
PCMark 8 provides a slightly different measurement, however, that we are terming as ‘Total Storage Latency’. This is represented as being the period from the time the last command was completed, until the time it took to complete the next task; the difference of course being that the execution of that task is included in ‘Total Storage Latency’. For both latency graphs, the same still exists where the lower the latency, the faster the responsiveness of the system will be. While both latency charts look very similar, the scale puts into perspective how just a few milliseconds can increase the length of time to complete multiple workloads.
For a more in-depth look into Latency, Bandwidth, and IOPS check out our primer article on them here.
AVERAGE BANDWIDTH (OR THROUGHPUT)
These results show the total average bandwidth across all tests in the 18 phases. In this graph the higher the result the better.
AVERAGE LATENCY (OR ACCESS TIME)
These results show the average access time during the workloads across all tests in the 18 phases. In this graph the lower the result the better.
TOTAL STORAGE LATENCY
These results show the total access time across all tests in the 18 phases. In this graph the lower the result the better.
For this test we used the 120GB Samsung 850 EVO. At first, average bandwidth shows us two things. One, heavy workloads seem to result in lower average bandwidth with RAPID, and two, once the typical consumer light workloads begin, we can see it boosts performance to nearly 3x. Furthermore, we can see that the average latency without RAPID mode reaches up to almost .6ms in the Degrade and Steady State phases. Once RAPID is enabled, latency is cut down to just under .3ms. Over the Recovery phases we can see decent performance of around 0.072ms for latency without RAPID, however, once again, with it enabled we can see an average of 0.023ms for its latency performance. Finally, the total latency, results show that while bandwidth was less in steady state performance, overall, the reduction of average latency significantly speed up the workloads.
REPORT ANALYSIS AND FINAL THOUGHTS
RAPID mode is a sweet extra feature that Samsung packed with their Magician Toolbox bundle. It allows for many Samsung SSD owners to enable RAM caching on their system in a quick and easy way. Once it is enabled, all the work is automated. The user can simply resume using the system as normal, but now performance is improved.
In testing, Samsung’s synthetic benchmark showed a night and day difference in performance with RAPID mode enabled, but it didn’t feel like it in our perceptible use of the system when enabled. To test out why, we benchmarked our startup time and application load times. As a result, startup was slower, but it was so minute a difference that it shouldn’t cause anyone to lose any sleep over it. Application load times also proved to gain no benefit, however, we were testing only the programs themselves at first. After testing some work files, it followed a similar trend. Recently accessed files should prove to have a faster retrieval speed after reboots, however they did not. Our testing methodology proved RAPID did not afford any benefit outside of Windows default caching behavior in these instances. It wasn’t until our workload testing was done that we saw a performance increase.
Our final testing with PCMark 8 gave us some better insight on how RAPID can improve a system’s performance. Average latency was cut in half and the total latency was cut down by more than that. The average bandwidth results proved something a bit different at first, steady state performance showed to be lower, but when in the recovery phase, average bandwidth shot up to speeds nearly triple to that of the system with RAPID disabled. Based upon our results, we can tell that RAPID actually does work and it really can significantly speed up real world performance.
So in all, RAPID does indeed increase a system’s performance. In day to day usage start up and opening application times will not be affected, however, when it comes to actually working on projects, RAPID will help to speed things up.