5 ms·

The benchmarks I have seen show Hotspot is ahead of V8. E.g. https://stefan-marr.de/papers/oopsla-larose-et-al-ast-vs-bytecode-interpreters-in-the-age-of-meta-c

The benchmarks I have seen show Hotspot is ahead of V8. E.g. https://stefan-marr.de/papers/oopsla-larose-et-al-ast-vs-bytecode-interpreters-in-the-age-of-meta-compilation/ https://stefan-marr.de/papers/oopsla-larose-et-al-ast-vs-byt... What makes this very complicated is that 1) language design plays a big part in performance and 2) CPUs change as well and this anecdotally seems to have more impact on interpreter than compiler performance. With regards to 1), consider optimizing Javascript. It doesn't have machine integers, so you have to do a bunch of analysis to figure when something is being used as an integer and then you can make that code fast. There are many other cases. Python is even worse in this regard. In comparison AOT compiled languages are usually designed to be fast, so they make tradeoffs that favour performance at the cost of some level of abstraction / expressivity. The JVM is somewhere in the middle, and so is its performance. With regards to 2) this paper is an example, as is https://inria.hal.science/hal-01100647/file/InterpIBr-hal.pdf https://inria.hal.science/hal-01100647/file/InterpIBr-hal.pd...

ajross 2y ago
With all respect that sounds like excuse-making. I mean, yeah, Javascript and JVM and .NET are slower runtimes than C or Rust[1]. Nonetheless that's the world we live in, and if you have a performance-sensitive problem to solve you pick up rustc or g++ and not a managed runtime. If that's wrong, someone's got to actually show that it's wrong. [1] Maybe Go or Swift would be more apples-to-apples. But even then are there clear benchmarks showing Kotlin or C# beating similar AoT code? If anything the general sense of the community is that Go is faster than Java.
- noelwelsh 2y ago
  Excuses for what? I'm not the elected representative for JIT compiled languages, sworn to defend them. There are technical reasons they tend to be slower. I was sketching some of them.
  - mrkeen 2y ago
    I think the above comments are because JIT gets so much positive press, someone wandering in from outside could be mistaken for thinking that JIT isn't coming 2nd in a two-man race with AOT. I've been around long enough to hear that Java and JIT are gonna overtake C++ any day now. The title on this article doesn't help.
- pca006132 2y ago
  When things are performance-sensitive, you want things to be tunable and predictable. Good luck playing with the JIT if you rely that for performance...
  - pjmlp 2y ago
    Good luck with AOT as well, unless you hardcode the target hardware, like game consoles.
- wiseowise 2y ago
  https://devblogs.microsoft.com/oldnewthing/20060731-15/?p=30293 https://devblogs.microsoft.com/oldnewthing/20060731-15/?p=30... https://blog.codinghorror.com/on-managed-code-performance-again/ https://blog.codinghorror.com/on-managed-code-performance-ag... And that was 2005. Modern .NET is much, much faster. > If anything the general sense of the community is that Go is faster than Java. Faster where?
MaxBarraclough 2y ago
> you have to do a bunch of analysis to figure when something is being used as an integer and then you can make that code fast It doesn't get much attention now that WASM exists, but asm.js essentially solves this, so a more head-to-head comparison ought to be possible. (V8 has optimisations specific to asm.js.) https://en.wikipedia.org/wiki/Asm.js https://en.wikipedia.org/wiki/Asm.js
- IainIreland 2y ago
  asm.js solves this in the specific case where somebody has compiled their C/C++ code to target asm.js. It doesn't solve it for arbitrary JS code. asm.js is more like a weird frontend to wasm than a dialect of JS.
  - lern_too_spel 2y ago
    No, if you just use the standard JavaScript cast to integer incantation, |0, v8 will optimize it. asm.js is valid JavaScript.
  - MaxBarraclough 2y ago
    Sure, but that was essentially my point. If we're trying to compare HotSpot and V8 for similar input code, Java and asm.js seem closer than Java and full-blown JavaScript with its dynamic typing.

ajross 2y ago

With all respect that sounds like excuse-making. I mean, yeah, Javascript and JVM and .NET are slower runtimes than C or Rust[1]. Nonetheless that's the world we live in, and if you have a performance-sensitive problem to solve you pick up rustc or g++ and not a managed runtime. If that's wrong, someone's got to actually show that it's wrong. [1] Maybe Go or Swift would be more apples-to-apples. But even then are there clear benchmarks showing Kotlin or C# beating similar AoT code? If anything the general sense of the community is that Go is faster than Java.

noelwelsh 2y ago
Excuses for what? I'm not the elected representative for JIT compiled languages, sworn to defend them. There are technical reasons they tend to be slower. I was sketching some of them.
- mrkeen 2y ago
  I think the above comments are because JIT gets so much positive press, someone wandering in from outside could be mistaken for thinking that JIT isn't coming 2nd in a two-man race with AOT. I've been around long enough to hear that Java and JIT are gonna overtake C++ any day now. The title on this article doesn't help.
pca006132 2y ago
When things are performance-sensitive, you want things to be tunable and predictable. Good luck playing with the JIT if you rely that for performance...
- pjmlp 2y ago
  Good luck with AOT as well, unless you hardcode the target hardware, like game consoles.
wiseowise 2y ago
https://devblogs.microsoft.com/oldnewthing/20060731-15/?p=30293 https://devblogs.microsoft.com/oldnewthing/20060731-15/?p=30... https://blog.codinghorror.com/on-managed-code-performance-again/ https://blog.codinghorror.com/on-managed-code-performance-ag... And that was 2005. Modern .NET is much, much faster. > If anything the general sense of the community is that Go is faster than Java. Faster where?

MaxBarraclough 2y ago

> you have to do a bunch of analysis to figure when something is being used as an integer and then you can make that code fast It doesn't get much attention now that WASM exists, but asm.js essentially solves this, so a more head-to-head comparison ought to be possible. (V8 has optimisations specific to asm.js.) https://en.wikipedia.org/wiki/Asm.js https://en.wikipedia.org/wiki/Asm.js

IainIreland 2y ago
asm.js solves this in the specific case where somebody has compiled their C/C++ code to target asm.js. It doesn't solve it for arbitrary JS code. asm.js is more like a weird frontend to wasm than a dialect of JS.
- lern_too_spel 2y ago
  No, if you just use the standard JavaScript cast to integer incantation, |0, v8 will optimize it. asm.js is valid JavaScript.
- MaxBarraclough 2y ago
  Sure, but that was essentially my point. If we're trying to compare HotSpot and V8 for similar input code, Java and asm.js seem closer than Java and full-blown JavaScript with its dynamic typing.