Memory Leak in Onnx Session Release [Web]

[kishorekaruppusamy]

Describe the issue

memory leak is found after doing session.release()

To reproduce

npm install -g memlab

unzip the zip file provided below and run index.html in some server and return that url in url() function in scenario_file.js

and just run

memlab run --scenario scenario_file.js
memlab find-leaks --trace-all-objects

you can see the leaks

Archive.zip

Urgency

Very Urgent Need this Fix For complete my project

ONNX Runtime Installation

Released Package

ONNX Runtime Version or Commit ID

1.18.0

Execution Provider

'wasm'/'cpu' (WebAssembly CPU)

[juliankolbe]

any updates on this one?

[fs-eire]

Sorry for late response.

I can reproduce the behavior. After looking at the logs carefully, I found that the biggest size of object is wasm2, which contains the WebAssembly array buffer buffer.

You may find some introduction to WebAssembly.Memory here. One unfortunate fact is, one Memory can "grow" but cannot "shrink". The WebAssembly instance always holds the reference to the WebAssembly.Memory, which keeps its size to the peak memory usage. For onnxruntime-web, the WebAssembly instance never reaches to its end of lifecycle so the memory usage is always kept.

Solution/Workaround:

Technically it is possible to allow uninitializing the WebAssembly instance. Once it's unintialized, if user want to create another new inference session, we do all the initialization steps again. However this may be actually difficult to do, because all existing code of onnxruntime-web are written based on the assumption that the WebAssembly instance is a singleton and will not change.

In practice, we usually use a workaround: create a web worker and import onnxruntime-web in the worker. once the developer think the page is done with onnxruntime-web, the worker can be terminated and all resources are collected.