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Two unique features that stand out with the OWC Mercury Extreme Pro RE SSD release are that performance will not be lost as the SSD fills and that it will remain intact over the life of the drive due to its 28% over provisioning. This certainly goes against the grain of what we have seen with SSDs historically and it has become common place to provide advise that degradation may start once filled passed the 60% mark. There have also been some observation that some SSDs would maintain peak performance only until all the NAND flash have been filled to capacity for the first time.
For those new to solid state drives, firmware of the drive includes wear leveling technology which allows the SSD to store information equally amongst NAND cells to allow maximum life of the NAND flash memory. When one describes a SSD as having being filled, it may simply mean that all the cells of the available RAM have been utilized at some point in time and not that the SSD is full.The SSD Review testing was simple. The OWC SSD had been completely written to or “filled” five times. The drive was then subject to further data storage starting at 50% and every 10% thereafter until full, to which Crystal Disk Mark and ATTO Benchmark performance testing was conducted at every level. An amusing observation was that when the OWC SSD was filled completely, the benchmark software would not function as there was no free space on the drive to write to. This answered the question as to whether any of the 28Gb of drive dedicated memory would be made available to the user as the SSD filled which was considered a possibility as performance is guaranteed regardless of how close to capacity it is.
The OWC Mercury Extreme Pro RE SSD has not diminished in performance under any testing condition since it was first benchmarked on arrival at The SSD Review. This is not a characteristic of any previous SSD release that we are aware of but, quite possibly, we may start to see it should another drive be released with matching controller and over provisioning. A similar Crystal Disk Score with the drive filled to capacity could not be found anywhere on the web.
Below are the original results of the OWC SSD on first installation (left) and then at the end of the evaluation when filled to capacity, the latter of which looks to actually be performing better.
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