Pre-load JavaScript kernel into memory for faster JS startup

[mishushakov]

Benchmarks

Execution time

Before:
Python kernel time taken: 64.61 milliseconds
JavaScript kernel time taken: 256.47 milliseconds

After:
Python kernel time taken: 64.32 milliseconds
JavaScript kernel time taken: 67.80 milliseconds

Memory usage

Before/after loading JavaScript kernel into memory (idle)

[linear]

E2B-2917 Pre-load JavaScript kernel into Code Interpreter

[cursor]

Bug: WebSocket Cleanup Fails on Initialization Error

A resource leak occurs if javascript_context creation fails. The python_context websocket, which was successfully created, is not cleaned up because the cleanup logic after yield is not reached when an exception occurs during initialization.

template/server/main.py#L37-L54

code-interpreter/template/server/main.py

Lines 37 to 54 in 38b491d

	try:
	python_context = await create_context(client, websockets, "python", "/home/user")
	default_websockets["python"] = python_context.id
	websockets["default"] = websockets[python_context.id]
	javascript_context = await create_context(client, websockets, "javascript", "/home/user")
	default_websockets["javascript"] = javascript_context.id
	logger.info("Connected to default runtime")
	yield
	# Will cleanup after application shuts down
	for ws in websockets.values():
	await ws.close()
	await client.aclose()
	except Exception as e:

 

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Comment @cursor review or bugbot run to trigger another review on this PR

[mishushakov]

I will be doing another PR for what Cursor said (although can be ignored)

[mishushakov]

Currently blocked by
#140