The biggest gains of Apple's M processors is behind us

Improvements in hardware are not linear. If we look at the performance of hardware over time, we can see that performance improvements follow a pattern: a sharp rise in performance followed by a period of little improvements. (A graph looks like a staircase, with the pattern of "rise, flat, rise, flat".)

The first implementation of a change provides significant increases. Over time, we refine the improvements and gain additional increases. But those later increases are smaller. Eventually, subsequent refinements provide minimal improvements. So we move on to other ideas.

The history of personal computers follows this pattern. We have made a number of changes to hardware that have improved performance. Each of those changes yielded a large initial gain, and then gradually diminishing improvements.

We have increased the clock speed.

We changed memory technology from "core" memory (ferrous rings) to transistor-based memory (static at first, and then dynamic memory).

We have added caches, to store values in processor, reducing the dependence on memory. We liked the idea of caches so much that we did it more than once. Processors now have three levels of caches.

We have off-loaded work to (smarter) devices. Devices now have their own processors and can perform tasks independently of the CPU.

We have increased the number of CPU cores, which improves performance for systems with multiple processes and multiple threads. (Which is just about every system we have today.)

Each of these changes improved performance. A large step up at first, and then smaller increases.

Now Apple has used another method to improve performance: Reduce distance between chips with system-on-a-chip designs. The M1 chips include all components of the computer: CPU, memory, storage, GPU, and more.

Yet the overall pattern of improvements will hold with this new design. The first M1 chip will have significant improvements over the older design of discrete components. The M1 Pro and M1 Max will have improvements over the M1 chip, but not larger than the initial M1 gains.

Later chips, such as the M2, M2 Pro, and even the M3, will have gains, but less and less (in terms of percentages) than the previous chips. The performance curve, after a sharp rise with the M1 chip, will flatten. Apple will have entered the "plain of modest gains" phase.

Apple's M1 chips are nice. They provide good performance. Newer versions will be better: faster, more powerful. But the biggest increases, I think, are already behind us.