The sometimes mediocre write speed on SSD doesnt really surprise considering how writing to flash cells work. When changing/overwriting data in a flash cell, the entire block (typically 16kb or more) has to be read to a buffer, modified and written back to the cell. This can lead to worst case scenarios of access times spiking to over 200ms for writing data. This is obviously not the case if the flash cell is already empty.
But it kills the myth of always 0.1ms random access times on SSD - at least as far as writing data goes.
I just wish more reviewers would use sophisticated benchmark tools such as
h2benchw instead of only hdtach or hdtune. It does a much better job - but also takes longer to spit out the numbers, obviously.
Discussion Zen 5 Speculation (EPYC Turin and Strix Point/Granite Ridge - Ryzen 9000)
Discussion Intel current and future Lakes & Rapids thread
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