Why Javascript engines are so slow?

[Nay Lin Tun]

On chess.com and lichess.com, the javascript stockfish analysis is extremely slower than normal UCI interface. In my computer, with UCI, I get around 10Mns (depth around 25-27 instantly) but with javascript I get only about 5Mns (depth around 20). While we can easily use playstation emulator or android emulator in Window program, why not between those two languages/instructions.

[hgm]

That is extremely fast, for JavaScript, isn't it? JavaScript is an intrinsically slow language, because the variables are untyped, and ca hold objects of any size. So that at run time you would have to keep track of what is in the variable, and how big it is. It must have a pretty smart compiler to be only twice slower as C.

Anything better than 5% of the speed of the equivalent C program should be considered a small miracle.

[mar]

On chess.com and lichess.com, the javascript stockfish analysis is extremely slower than normal UCI interface. In my computer, with UCI, I get around 10Mns (depth around 25-27 instantly) but with javascript I get only about 5Mns (depth around 20). While we can easily use playstation emulator or android emulator in Window program, why not between those two languages/instructions.

Only 2x slower compared to native C++? They probably used emscripten, webassembly should do even better in the near future.

Do you understand that Javascript is a dynamic language and those are extremely difficult to JIT?
That's also why modern Javascript VMs are extremely complex.
Many years ago javascript was interpreted, imagine how that would run.

[gbtami]

On chess.com and lichess.com, the javascript stockfish analysis is extremely slower than normal UCI interface. In my computer, with UCI, I get around 10Mns (depth around 25-27 instantly) but with javascript I get only about 5Mns (depth around 20). While we can easily use playstation emulator or android emulator in Window program, why not between those two languages/instructions.

Only 2x slower compared to native C++? They probably used emscripten, webassembly should do even better in the near future.

Do you understand that Javascript is a dynamic language and those are extremely difficult to JIT?
That's also why modern Javascript VMs are extremely complex.
Many years ago javascript was interpreted, imagine how that would run.

As Niklas Fiekas said they use WebAssembly:
http://talkchess.com/forum/viewtopic.php?t=63404

[gbtami]

On chess.com and lichess.com, the javascript stockfish analysis is extremely slower than normal UCI interface. In my computer, with UCI, I get around 10Mns (depth around 25-27 instantly) but with javascript I get only about 5Mns (depth around 20). While we can easily use playstation emulator or android emulator in Window program, why not between those two languages/instructions.

Do you see this slowness with WASM on on lichess.org?
https://en.lichess.org/blog/WPSD5icAAKM ... on-lichess

[Nordlandia]

Static evaluation can be found on this site ->

https://hxim.github.io/Stockfish-Evaluation-Guide/

[Guenther]

Static evaluation can be found on this site ->

https://hxim.github.io/Stockfish-Evaluation-Guide/

Is this a random 'computerchess bot' post?
It has absolutely nothing to do with this thread...

[styx]

The lichess.org local chess engine is no javascript. It's PNACL for Chrome and WASM for Firefox >=v52.0

It allows to run code written in several languages (C++ for Stockfish) in your browser at near native speed.

But as you experienced, it's still not 100% as fast as your native engine in your favorite GUI. But still - much faster than Javascript

[tmokonen]

Static evaluation can be found on this site ->

https://hxim.github.io/Stockfish-Evaluation-Guide/

Is this a random 'computerchess bot' post?
It has absolutely nothing to do with this thread...

It was obviously meant to be posted in a different thread. People do click the wrong button sometimes. I am not sure why you would be so upset about it.