PCPer File Copy Test
Our custom PCPer-FC test does some fairly simple file creation and copy routines in order to test the storage system for speed. The script creates a set of files of varying sizes, times the creation process, then copies the same files to another partition on the same hard drive and times the copy process as well. There are four file patterns that we used to try and find any strong or weak points in the hardware: 10 files @ 1000 MB each, 100 files @ 100 MB each, 500 files @ 10 MB each and 1000 files at 1 MB each.
We see a general trend here, where the middle two capacities (256 and 512GB) appear to be in a performance 'sweet spot', while the 128GB and 1TB models are just slightly slower. This can be explained by a lower die count (and therefore less parallelism) in the 128GB model. For the 1TB model, it might be attributed to controller addressing limits, as addressing 1TB worth of (likely 16MB) flash pages is not an easy task. We've seen a similar effect with SandForce controlled SSDs, however the effect is much more subtle with the more powerful Marvell controller crunching the numbers.