Re:Why is Apple's M1 chip so fast?
by brandmeyer on Monday November 30, 2020 @07:56PM
(#25261006)
Big cache lines and big pages together. 16 kB pages combined with 128-byte lines means it can be 8-way set associative and still take advantage of a VIPT structure.
Larger pages mean that performance on memory-mapped small files will suffer... which is a use-case that Apple doesn't normally care about in its client computers.
Larger cache lines mean that highly mulththreaded server loads could suffer from false sharing more often. Again, its a client computer so who cares?
Regarding the definition of "huge": A64FX uses 256B cache lines. Granted its a numerical computing vector machine, but still. Huge covers a lot of ground.
Larger pages mean that performance on memory-mapped small files will suffer... which is a use-case that Apple doesn't normally care about in its client computers.
Larger cache lines mean that highly mulththreaded server loads could suffer from false sharing more often. Again, its a client computer so who cares?
Regarding the definition of "huge": A64FX uses 256B cache lines. Granted its a numerical computing vector machine, but still. Huge covers a lot of ground.