FSNode Memory Leak?

[ryan-weisenberger]

I'm posting this as a discussion, because I'm really not sure this is an emscripten problem versus a wasm problem.

We have a memory leak when calling our WASM through javascript generated by emscripten 3.1.19.

Our WASM converts a CSV file to a binary file in memory. Every time the converter finishes, it leaves behind a FSNode object. So after several hundred conversions, we get several hundred of these FSNode objects clogging up memory.

I'm using Node's v8.getHeapSnapshot() to take a heap snap before the conversions, after the conversions, and again after I have forced run the GC. I'm attaching those snapshots here.

The number of FSNode objects left over exactly matches the number of conversions. In this case, 978.

We've gone over the WASM code quite extensively, and cannot find a memory leak.

Any ideas what could cause this, and how to resolve it? If this looks like an emscripten problem, I can move this to Issues.

heapSnapshots.zip

Thanks,
Ryan

[ryan-weisenberger]

This was caused by files being created in the virtual file system, and then not removed. See: #17739