4 ms·

This is super cool, I didn't know JavaScriptCore consistently outperformed V8 And SpiderMonkey seems... not up there compared to the other 2

by gunwd 9mo ago

DarkFuture 9mo ago
Disappointing for Firefox for such lower performance. I just ran the JetStream2 benchmark and got: - Firefox: 159 score - Chromium: 235 score That's on latest Fedora Linux and Ryzen 3600 CPU.
- p_ing 9mo ago
  M2 Air w/ 24GB RAM macOS 26.2: - Firefox: 253.584 - Safari: 377.470 - Chrome: 408.332 - Edge: 412.005
  - quantum_bit 9mo ago
    My results similar with M4 Pro (12 cores, 16 cores GPU), 24 GB RAM macOS 26.2 (the same benchmarks, I guess, https://browserbench.org/JetStream2.0/ https://browserbench.org/JetStream2.0/): 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.
- tralarpa 9mo ago
  Similar results here. 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.
  - 360MustangScope 9mo ago
    The developers are busy ramming AI into it by management. This is probably never going to get looked into.
  - nicoburns 9mo ago
    > Maybe the canvas operations are particularly slow on Firefox 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. --- SpiderMonkey is also now just quite a bit slower than V8 which may contribute.
forgotpwd16 9mo ago
Interesting how V8 to JSC ~2x LOC but ~2/3 the binary size.
- esprehn 9mo ago
  The size difference is so large it makes me wonder if one is being compiled with ICU and the other without.
- tracker1 9mo ago
  Comments and formatting can account for that difference in LOC though... not always directly comparable. Haven't looked, but variances with different assembly bits can make a big difference too.
aurareturn 9mo ago
That’s the promise of Bun - that it is faster because it uses JavascriptCore.
- gurgunday 9mo ago
  Bun is faster because it implements pretty much everything natively and just exposes them in JS, not because it uses JSCore 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] — https://v8.dev/blog/leaving-the-sea-of-nodes https://v8.dev/blog/leaving-the-sea-of-nodes — https://v8.dev/blog/maglev https://v8.dev/blog/maglev
  - lionkor 9mo ago
    > Google has a lot more incentive than Apple to make the fastest engine What are those incentives? I see no incentive for Google to make something fast.
    - charcircuit 9mo ago
      Faster page load times increases engagement with the web. More engagement on the web leads to more engagement with Google's ads.
      - lionkor 9mo ago
        I don't agree. Page load times do not matter when everything is so locked down that most people don't even know there's an alternative.
      - aurareturn 9mo ago
        But this was always true. True for last 40 years. What’s changed in 2026 that will motivate Google to overtake JSCore?

This is super cool, I didn't know JavaScriptCore consistently outperformed V8 And SpiderMonkey seems... not up there compared to the other 2

by gunwd 9mo ago

This is super cool, I didn't know JavaScriptCore consistently outperformed V8 And SpiderMonkey seems... not up there compared to the other 2

DarkFuture 9mo ago

Disappointing for Firefox for such lower performance. I just ran the JetStream2 benchmark and got: - Firefox: 159 score - Chromium: 235 score That's on latest Fedora Linux and Ryzen 3600 CPU.

p_ing 9mo ago
M2 Air w/ 24GB RAM macOS 26.2: - Firefox: 253.584 - Safari: 377.470 - Chrome: 408.332 - Edge: 412.005
- quantum_bit 9mo ago
  My results similar with M4 Pro (12 cores, 16 cores GPU), 24 GB RAM macOS 26.2 (the same benchmarks, I guess, https://browserbench.org/JetStream2.0/ https://browserbench.org/JetStream2.0/): 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.
tralarpa 9mo ago
Similar results here. 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.
- 360MustangScope 9mo ago
  The developers are busy ramming AI into it by management. This is probably never going to get looked into.
- nicoburns 9mo ago
  > Maybe the canvas operations are particularly slow on Firefox 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. --- SpiderMonkey is also now just quite a bit slower than V8 which may contribute.

forgotpwd16 9mo ago

Interesting how V8 to JSC ~2x LOC but ~2/3 the binary size.

esprehn 9mo ago
The size difference is so large it makes me wonder if one is being compiled with ICU and the other without.
tracker1 9mo ago
Comments and formatting can account for that difference in LOC though... not always directly comparable. Haven't looked, but variances with different assembly bits can make a big difference too.

aurareturn 9mo ago

That’s the promise of Bun - that it is faster because it uses JavascriptCore.

gurgunday 9mo ago
Bun is faster because it implements pretty much everything natively and just exposes them in JS, not because it uses JSCore 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] — https://v8.dev/blog/leaving-the-sea-of-nodes https://v8.dev/blog/leaving-the-sea-of-nodes — https://v8.dev/blog/maglev https://v8.dev/blog/maglev
- lionkor 9mo ago
  > Google has a lot more incentive than Apple to make the fastest engine What are those incentives? I see no incentive for Google to make something fast.
  - charcircuit 9mo ago
    Faster page load times increases engagement with the web. More engagement on the web leads to more engagement with Google's ads.
    - lionkor 9mo ago
      I don't agree. Page load times do not matter when everything is so locked down that most people don't even know there's an alternative.
    - aurareturn 9mo ago
      But this was always true. True for last 40 years. What’s changed in 2026 that will motivate Google to overtake JSCore?