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2012 MBP Retina — Apple 500GB SSD Performance
The internal SSD that Apple supplies is a fast 6G SSD (“Apple SSD SM512E”, apparently Samsung). Apple calls this “flash storage”, which is another name for SSD (solid state drive).
Note that Apple claims it is a 512GB SSD, which is the usual Apple advertising fraud, since the user sees just under 500GB of actual storage.
DiskTester fill-volume performance
This is a sequential speed test, the most important performance metric for Photoshop and similar programs for real-world usage.
The drive was tested with about 44GB of system install in place; this has no material effect on the results.
All speed are real-world, including operating system file system overhead, not unrealistic driver-level calls.
Speeds shown are for highly compressible data (zeroes), as well as a purely random stream of data (worst possible case for some SSDs).
The Apple-supplied SSD is a very good performer. Will its speed hold up over the long term? This test does not address that potential issue.