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What makes WebAssembly fast?

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Re: What makes WebAssembly fast?

#31

Post by johncolanduoni »

mstade wrote: post #24
dmarcos wrote: post #9

Earlier quoted context omitted.

WebAssembly won't give you unlimited power. You will still have the browser sandboxing and security / privacy policies in place. Accessing to the local file system is for instance constrained in the browser for good reasons. WebAssembly apps will be able to do what Web APIs let any page do.

Is this universally true – i.e. baked in to the wasm spec – or is it just true in a browser environment? Consider things like NW.js[1] or Electron[2] – might we see cross platform apps being developed where all or parts of it are written in and compiled to wasm, then packaged up with a runtime and delivered as a "native" application for desktop, mobile, or whatever? [1]: https://nwjs.io [2]: https://electron.atom.io

No, the wasm spec doesnt mention web standards at all. It can be implemented without a JavaScript VM nearby, and at the moment isn't even capable of interacting with the DOM/JavaScript APIs directly when it is run in web browsers.

Re: What makes WebAssembly fast?

#32

Post by andrewbinstock »

astrodust wrote: post #2

It's both amusing and absurd that what was practically intended as Java's little helper, JavaScript, has grown up to be this thing that might actually replace Java entirely. How long until there's a really good JVM written in JavaScript of some form and embedded Java apps end up running in JavaScript for performance and security reasons? It'll be even more ridiculous and hilarious if the "j" in "jruby" ends up meanin…

>How long until there's a really good JVM written in JavaScript of some form and embedded Java apps end up running in JavaScript for performance and security reasons?

Much of the JVM is written in C++ (From the docs: "There are nearly 1500 C/C++ header and source files, comprising almost 250,000 lines of code.")

Re: What makes WebAssembly fast?

#33

Post by brlewis »

amorphid wrote: post #12
astrodust wrote: post #2

It's both amusing and absurd that what was practically intended as Java's little helper, JavaScript, has grown up to be this thing that might actually replace Java entirely. How long until there's a really good JVM written in JavaScript of some form and embedded Java apps end up running in JavaScript for performance and security reasons? It'll be even more ridiculous and hilarious if the "j" in "jruby" ends up meanin…

Until JavaScript offers a robust concurrency abstraction, I don't see it completely replacing anything that is used for that purpose.

Based on the comment you're replying to I infer that you think Java offers a robust concurrency abstraction.

I disagree. In moving to the single-threaded async style of JS concurrency, the hardest part for me has been to rid myself of the ugly habit I acquired from Java's threading model, i.e. asking myself at each line of code, what happens if my thread gets preempted here?

Re: What makes WebAssembly fast?

#34

Post by Svenskunganka »

> In the last article, I explained that programming with WebAssembly or JavaScript is not an either/or choice. We don’t expect that too many developers will be writing full WebAssembly code bases.

I see this statement all the time, but it doesn't make sense. If you're looking at any programming language out there, they all have a growing members of their community asking and showing interest in targeting WebAssembly for their language of choice. It's not just C/C++. Go, Rust, Ruby, Python, Crystal, Nim, D, and many more. Now you might get the reaction that "meh, why would anyone write web apps with Rust?", but that's an irrelevant question. Companies are going to see this as an opportunity to save resources and become more efficient, especially since wasm has so much better perf than JITed JS and the possibility of going isomorphic is a reality (back-end & front-end written in Ruby for example, deriving from the exact same codebase and shares code).

Now I'm not saying "WebAssembly will take over JS!", what I'm saying is that it perhaps, possibly, maybe will. It will depend on these languages and how they add support for it, what abstractions and integrations they provide with their current ecosystems. And of course, how WebAssembly will improve over the coming years.

Re: What makes WebAssembly fast?

#35

Post by callahad »

pmontra wrote: post #28

> At least for now, WebAssembly does not support garbage collection at all. Memory is managed manually (as it is in languages like C and C++). While this can make programming more difficult for the developer, it does also make performance more consistent. Ouch, back to the 80s, early 90s. I think I'll stick with JavaScript at least until WebAssembly gets garbage collection. I might be wrong but I don't see many peopl…

You don't have to go back to the 80's to develop closer to the metal. Neither Rust nor Swift have garbage collection, but both are thoroughly modern, productive languages. I've also been told that C++14 is reasonably pleasant, but I have no personal experience with which to judge.

Re: What makes WebAssembly fast?

#36

Post by lanna »

dominotw wrote: post #18
astrodust wrote: post #2

It's both amusing and absurd that what was practically intended as Java's little helper, JavaScript, has grown up to be this thing that might actually replace Java entirely. How long until there's a really good JVM written in JavaScript of some form and embedded Java apps end up running in JavaScript for performance and security reasons? It'll be even more ridiculous and hilarious if the "j" in "jruby" ends up meanin…

>has grown up to be this thing that might actually replace Java entirely. Java is just a language that runs on JVM, there have been many many attempts to replace it with languages brand new ( scala), existing languages ( jruby) including javascript( nashorn/ringojs ect), but no language has even come close to dethroning it. Its unlikely that javascript will replace it just because jvm is rewritten in java script.

> Its unlikely that javascript will replace it just because jvm is rewritten in java script.

that is not what oc meant. he is talking about runtime env, not source language

Re: What makes WebAssembly fast?

#37

Post by nessus42 »

astrodust wrote: post #2

It's both amusing and absurd that what was practically intended as Java's little helper, JavaScript, has grown up to be this thing that might actually replace Java entirely. How long until there's a really good JVM written in JavaScript of some form and embedded Java apps end up running in JavaScript for performance and security reasons? It'll be even more ridiculous and hilarious if the "j" in "jruby" ends up meanin…

> How long until there's a really good JVM written in JavaScript of some form and embedded Java apps end up running in JavaScript for performance and security reasons?

That's an amusing idea. But it's extremely unlikely for the same reason that you are unlikely to see C++ rewritten in JavaScript.

It's possible, however, that over time, more and more languages might target JavaScript, rather than the JVM or the native hardware.

For instance, I program in Scala for a living. The main platform for Scala is the JVM, but there's also Scala.js, which targets JavaScript. And in fact, we now write most of our "JavaScript" in Scala, rather than in JavaScript.

I suppose that someday there might be a version of Java that targets JavaScript, and then your dream might come true. Oh wait... it already happened! It's called GWT and it's been around for a decade.

Re: What makes WebAssembly fast?

#38

Post by verletx64 »

pmontra wrote: post #28

> At least for now, WebAssembly does not support garbage collection at all. Memory is managed manually (as it is in languages like C and C++). While this can make programming more difficult for the developer, it does also make performance more consistent. Ouch, back to the 80s, early 90s. I think I'll stick with JavaScript at least until WebAssembly gets garbage collection. I might be wrong but I don't see many peopl…

Isn't WASM a compile target?

Re: What makes WebAssembly fast?

#39

Post by brlewis »

zeveb wrote: post #29
nessus42 wrote: post #26

Earlier quoted context omitted.

I'm a HUGE fan of Scheme. And of Lisp, in general. But having seen in the "real world" how so many people are so adverse to Lisp's beautiful syntax, I'm pretty confident that JavaScript would never have caught on if it looked like Lisp rather than like C.

They wouldn't have had a choice, though, just as folks don't have a choice with JavaScript. I imagine that folks would have cottoned on to the advantage pretty quickly. And those that didn't … I guess they could have always become telephone cleaners or something:-)

Pure Scheme would not be sufficient. You need at least DOM-handling libraries. And if those libraries were poorly designed, then people wouldn't cotton onto the advantage quickly. Look at DSSSL.

Re: What makes WebAssembly fast?

#40

Post by tmzt »

zeveb wrote: post #29
nessus42 wrote: post #26

Earlier quoted context omitted.

I'm a HUGE fan of Scheme. And of Lisp, in general. But having seen in the "real world" how so many people are so adverse to Lisp's beautiful syntax, I'm pretty confident that JavaScript would never have caught on if it looked like Lisp rather than like C.

They wouldn't have had a choice, though, just as folks don't have a choice with JavaScript. I imagine that folks would have cottoned on to the advantage pretty quickly. And those that didn't … I guess they could have always become telephone cleaners or something:-)

Well we could all be using VBScript. If Netscape had failed to establish a defacto standard, Microsoft was waiting in the wings.
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