News for hackers. Stuff that matters.

A comment on Apple’s new M1 Pro and M1 Max processors. Parent comment

Re:Apple’s new M1 Pro and M1 Max processors by astrange on Monday October 18, 2021 @09:51PM (#28914010)
Measuring memory usage is a complicated topic and just adding numbers up overestimates it pretty badly. The different priorities of memory are something like 1. wired (must be in RAM) 2. dirty (can be swapped) 3. purgeable (can be deleted and recomputed) 4. file backed dirty (can be written to disk) 4. file backed clean (can be read back in).

Also note M1's unified memory model is actually worse for memory use not better. Details left as an exercise for the reader.

[ Parent | on HN ]
Re:Apple’s new M1 Pro and M1 Max processors by simonh on Tuesday October 19, 2021 @04:19AM (#28915967)
Unified memory is a performance/utilisation tradeoff. I think the thing is it's more of an issue with lower memory specs. The fact you don't have 4GB (or even 2 GB) dedicated memory on a graphics card in a machine with 8GB of main memory is a much bigger deal than not having 8GB on the graphics card on a machine with 64 GB of main RAM.
[ Parent | on HN ]