iswasmfast

At a glance, the bindings for wasm copy the data, https://github.com/zandaqo/iswasmfast/blob/54bbb7b539c127185... If the running code is short enough then that copy might easily make the wasm version much slower. That is indeed a known downside of wasm (calls to JS are somewhat slow, and copying of data even more so - wasm shines when you can avoid those things, which certainly limits where it makes sense!). If it's not that, then a 10x difference suggests you are running into some kind of a VM bug or limitation.

> “Near-Native Performance”: Wasm is often described as having “near-native performance”. What this actually means is that WebAssembly is almost always faster than JavaScript, especially for compute-intensive workloads, and averages between 1.45 and 1.55 times slower than native code, but results do vary by runtime. Yeah, nah: https://github.com/zandaqo/iswasmfast JS is about 10x faster than wasm in simple linear regression, and 30% faster in levenstein distance calculation.

WASM has its moments, as you can see in this[1] benchmark it outperforms JS and native addons on certain tasks. Since the bottleneck with native addons is usually data copying/marshalling, and we have direct access to WebAssembly memory from the JavaScript side, using WebAssembly on this "shared" memory might become the best approach for computationally heavy tasks. I wrote about it a bit here[2]. [1] https://github.com/zandaqo/iswasmfast [2] https://medium.com/swlh/structurae-1-0-graphs-strings-and-we...

A few years ago I did similar comparison but in context of Node.js and sans manual optimizations: https://github.com/zandaqo/iswasmfast In my work, I have come to conclusion that it seldom pays off to go "native" when working with Node.js. More often than not, rewriting some computationally heavy code in C and sticking it as a native module yielded marginally better results when compared with properly optimized js code. Though, that doesn't negate other advantages of using said technologies: predictable performance from the start and re-using existing code base.

I have done some benchmarking comparing JS, WASM, and native C++ addon performance in Node.js: https://github.com/zandaqo/iswasmfast From the look of it, in Node.js, WASM suffers less data exchange overhead while been decently close to performance of the native addons.