loaders.gl/las OOM Error

[gchoqueux]

We use loaders.gl/las to load a large cloud with a multitude of laz files (entwine cloud).
Then we visualize them simultaneously from hundreds of laz files with a library THREE.js.

After uploading hundreds of files, the loaders.gl/las throwns OOM Error.
It seems that this error is thrown when emscripten can't resize memory heap.

Is there a memory leak?
Is there a memory limit?
is possible to free the loaders.gl/las memory?

We have a open issue iTowns/itowns#1721

[ibgreen]

If you are using the default setup, you are probably using the worker loader.

You can set a flag to destroy the worker loader after each load: https://loaders.gl/docs/developer-guide/using-worker-loaders#disabling-reuse-of-workers. Perhaps using a fresh loader for each load will help?

[gchoqueux]

Thank you for the answer.

I don't use the load method, I use directly the parser with the method LASLoader.parse.
The options worker and reuseWorkers are used in the parser?

[ibgreen]

No you would need to use load() or parse().

[gchoqueux]

The parse() method fixes the OOM error, with options { worker: true, reuseWorkers: false }
But they are replaced by warnings from las-worker.js :

• On Chrome : Invalid asm.js: Unexpected token
• On Firefox : asm.js type error: expecting argument type declaration for 'n' of the form 'arg = arg|0' or 'arg = +arg' or 'arg = fround(arg)' las-worker.js:1:62997

Of course, the warnings disappear if worker: false.

[ibgreen]

Haven't seen these. The LASLoader appears to work on the loaders.gl website: https://loaders.gl/examples/pointcloud (and I can see the las worker has started in the Thread inspector).

Are these just warnings? Do the point clouds actually load?

Not sure how to help...

[gchoqueux]

Yes, the point cloud files are loaded with parse(data, LASLoader, { worker: true, reuseWorkers: false }) and worker has started.

As I load thousands of files, I get thousands of asm/worker warnings.

[ibgreen]

@gchoqueux Sorry for slow reply.

In contrast to most loaders.gl loaders, the LAS loader is just a wrapper around a pre-compiled asm.js file (presumably the original source code is in C++). See https://github.com/verma/plasio.

I will close this issue as unfortunately, I do not have a lot of knowledge about asm.js and browser differences related to that.

I can say that long-term it would be very desirable to move to a pure Javascript (Typescript) LAS loader implementation. That would make this important loader much easier to maintain.

[gchoqueux]

ok, thanks

[greenwood-vaarst]

@gchoqueux did you ever resolve this? I'm having the same issue

ignore me, parse(data, LASLoader, { worker: true, reuseWorkers: false }) worked for me as well, with no warnings...