No one should care about single core performance these days. It just feels so deceptive. Workloads that are heavy are usually parallelized to use the chip fully. If performance is important, the portability and power efficiency aspect also becomes a bit contrived.

In broad strokes, a computationally heavy task that would be set up during the evening and be ready the next morning on a high end desktop wouldn't be ready on an M1 for a week.

> No one should care about single core performance these days.

Javascript is still single core bound, and that's often a bottleneck for consumer computer use.

Can't it start multiple threads to take advantage of multiple cores?

I'm not sure how well browsers on MacOS utilizes cores, or if there is an artificial restriction there. At the very least it will have a separate thread for each tab.

Though, if I'm not mistaken, I do believe that Web Workers is supported on all major browsers, including Safari. This allows the main JS thread (the one per tab) to spin up additional separate threads for other workloads. This page seems to confirm this: https://caniuse.com/webworkers

Here is an example to try out: https://codepen.io/prosetech/embed/qeqGQR? (source: [1]). When I tried it in chrome (default settings on linux) with a search range of 1 to 5,000,000, it took roughly 16 seconds and overall CPU usage was around 12%. Feel free to try it on an M1 (I'm genuinely curious, since comparable benchmarks are really hard to come by). This doesn't use the GPU at all, and is already CPU resource restricted, so I would expect it to fare well.

I'm sure the browser will handle some scheduling to limit 100% usage regardless of what the OS allows it.

So, it is I said before. That it seems a bit dishonest to exclusively focus on single core performance, as if that matters more than what the CPU can do when fully utilized. And, when fully utilized, the M1 is not remarkable in the slightest. It was a seriously misleading and dishonest marketing campaign. The only exception is, power consumption, which is pretty good. I find the idea of needing a lot of computing power, while also being limited by battery life, to be a contrived scenario. Wouldn't you be plugged in? Even the trains I've been to in recent memory have had power outlets.

With all that said, I think it's silly to consider javascript performance to be all that relevant. I hope this doesn't come across as a gatekeeping point of view. But when I talk about computing power, I don't really think about whether a web-page loads in 100 ms or 110 ms. But rather of machine learning tasks, photoshop filters. A software compilation. A blender render. Whether these things take 14 hours, or 1 hour. Which is what you can expect to be the difference in performance when fully utilizing a top end desktop GPU+CPU vs the M1. A practical difference of a "see you tomorrow morning", vs "see you in a week".

[1]: https://medium.com/young-coder/a-simple-introduction-to-web-...

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