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Comment by n9 | Hacker News Reader

You know that RAM in these machines is more different than the same as "RAM" in a standard PC? Apple's SoC RAM is more or less part of the CPU/GPU and is super fast. And for obvious reasons cannot be added to.

Anyway, I manage a few M1 and M3 machines with 256/8 configs and they all run just as fast as 16 and 32 machines EXCEPT for workloads that need more than 8GB for a process (virtualization) or workloads that need lots of video memory (Lightroom can KILL an 8GB machine that isn't doing anything else...)

The 8GB is stupid discussion isn't "wrong" in the general case, but it is wrong for maybe 80% of users.

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> EXCEPT for workloads that need more than 8GB for a process

Isn't that exactly the upthread contention: Apple's magic compressed swap management is still swap management that replaces O(1) fast(-ish) DRAM access with thousands+ cycle page decompression operations. It may be faster than storage, but it's still extremely slow relative to a DRAM fetch. And once your working set gets beyond your available RAM you start thrashing just like VAXen did on 4BSD.

Exactly! Load a 4GB file and welcome the beach ball spinner any time you need to context switch to another app. I don't know how they don't realize that because it's not really hard to get there. But when I was enamored with Apple stuff in my formative years, I would gladly ignore that or brush it off so I can see where they come from, I guess.

It's not as different as the marketing would like you to think. In fact, for the low-end models even the bandwidth/speed isn't as big of a deal as they make it out to be, especially considering that bandwidth has to be shared for the GPU needs.

And if you go up in specs the bandwidth of Apple silicon has to be compared to the bandwidth of a combo with dedicated GPU. The bandwidth of dedicated GPUs is very high and usually higher than what Apple Silicon gives you if you consider the RAM bandwidth for the CPU.

It's a bit more complicated but that's marketing for you. When it comes to speed Apple RAM isn't faster than what can be found in high-end laptops (or desktops for that matter).

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