Hmm, mine is only a 256GB drive. After making some room, I now have 53GB of free space, which means over 20% of it is free
I restarted my machine, re-ran the test and my write speed now settles at around 249MB/s for a 2GB file test, and around 180MB/s for anything bigger.
I can't really make more room, but it's odd that it should require so much free space. It also seems odd that write speeds start so high, but then start to come down pretty quick.
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