3 ms·
Huge block size (128bytes). Probably they are using Power7 alike scheduling (i.e. scheduling are working on packs of instructions, That might explain the humoro
by xpuente 6y ago
Huge block size (128bytes). Probably they are using Power7 alike scheduling (i.e. scheduling are working on packs of instructions, That might explain the humorous 600+ entry ROB. Certainly the wake-up logic can't deal with that one-by-one with such a low power). If you combine that with JIT and/or good compilers, you get this. I guess only Apple can pull this trick: they control all the stack (and some key power architects are working there).
- brandmeyer 6y agoBig 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.