This is super cool, I didn't know JavaScriptCore consistently outperformed V8
And SpiderMonkey seems... not up there compared to the other 2
And SpiderMonkey seems... not up there compared to the other 2
I believe long term, V8 will become the undisputed champ again as Google has a lot more incentive than Apple to make the fastest engine, but this is just a wild guess of mine, and I'm biased being a Node.js Collaborator
I've been hearing for a while that JSCore has a more elegant internal architecture than V8, and seeing the V8 team make big architectural changes as we speak seems to support it [1], but like I said, hopefully they will pay off long term
[1]
What are those incentives? I see no incentive for Google to make something fast.
What’s changed in 2026 that will motivate Google to overtake JSCore?
Why would Google have more incentive than Apple to make the fastest engine? Safari being the fastest mobile browser is important to Apple.
If Google had a stronger incentive than Apple, we would have seen V8 being more performant by now.
[0]https://web.archive.org/web/20220724110148/https://bun.sh/
Little faster? Like I said, that's not a *main* benefit as it's not why Bun can be 5 to 10x faster than Node.js
If we believe there is limit to everything, then the only sane conclusion would be v8 and JSC would both perform nearly the same with negligible difference in the long term. So choosing something that is fast, simple to integrate now makes a lot more sense.
Of course that is assuming memory usage, security and others being equal.
I just ran the JetStream2 benchmark and got:
- Firefox: 159 score
- Chromium: 235 score
That's on latest Fedora Linux and Ryzen 3600 CPU.
- Firefox: 253.584
- Safari: 377.470
- Chrome: 408.332
- Edge: 412.005
Firefox: 298.136
Safari: 425.762
Just the last test in this test suite:
> 3d-cube-SP > 3D cube rotation benchmark by Simon Speich. The original can be found on Simon's web page. Tests arrays and floating-point math in relatively short-running code.
gives the following results:
Firefox: 305.197
200 First 338.983 Worst 419.309 Average
Safari: 818.449
238.095 First 176.471 Worst 1957.237 Average
which shows that in this particular test, Safari is 2.5 times faster.
I'm curious to know what the problem of Firefox is. For example, the 3d-raytrace-SP benchmark is nearly three times faster on Edge than on Firefox on my i7 laptop. The code of that benchmark is very simple and mostly consists of basic math operations and array accesses. Maybe the canvas operations are particularly slow on Firefox? This seems to be an example that developers should take a look at.
That seems likely. WebRender (Firefox's GPU accellerated rendering backend) doesn't do vector rasterization. So Firefox rasterizes vectors using the CPU-only version of Skia and then uploads them to the GPU as textures. Apparently the upload process is often the bottleneck.
In contrast, Chrome uses (GPU-accelerated) Skia for everything. And Skia can render vector graphics directly into GPU memory (at least part of the rasterization pipeline is GPU accelerated). I would expect this to be quite a bit faster under load.
It's a known problem, but I hear that almost all of the Gecko graphics team's capacity beyond general maintenance is going towards implementing WebGPU.
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SpiderMonkey is also now just quite a bit slower than V8 which may contribute.