[deanq]

Summary

uv pip install does not compile bytecode by default. The published runpod/flash-cpu:latest ships with zero .pyc for runpod and aiohttp, so every fresh container recompiles each imported module on first import, on every cold start.

• --compile-bytecode on the build-time uv pip install in all four Dockerfiles
• python -m compileall -q . for the worker source in /app
• Deliberately a flag, not ENV UV_COMPILE_BYTECODE=1: an env var would leak into runtime installs in dependency_installer.py, where compiling whole packages at boot would add to cold start

Impact (arm64 CPU image, local builds, main vs this branch)

	main	this branch
.pyc runpod / aiohttp	0 / 0	80 / 55
Image size	177.1MB	187.9MB
Cold-container import runpod.serverless (6 fresh containers)	1177-1198ms	594-623ms

Image ships runpod 1.10.1; absolute numbers drop further once the worker moves to runpod 2.0 (lazy imports).

Test plan

• Built Dockerfile-cpu locally; verified .pyc present and measured cold-container import before/after
• GPU / LB images build in CI (amd64-only, not built locally; identical one-line change)
• Confirm cold-start delta on a real amd64 worker

Note for local testing on Apple M4-class Macs: arm64 images SIGILL in cryptography (OpenSSL SME detection inside the Docker VM) on main as well; run with -e OPENSSL_armcap=0.

Linear: SLS-809 (related: SLS-808)

[Copilot]

🟢 Approval recommended

The consistent, build-only changes preserve interpreter selection and runtime installation behavior, with no blocking issues identified.

No open issues 🎉

What changed in this PR

Reduces worker cold-start overhead by precompiling Python bytecode during image builds.

Changes:

• Enables dependency bytecode compilation in all four images.
• Precompiles worker source under /app.
• Keeps compilation build-scoped without changing runtime dependency installs.

File	Description
Dockerfile-lb-cpu	Precompiles dependencies and source for CPU load-balanced workers.
Dockerfile-lb	Precompiles dependencies and source for GPU load-balanced workers.
Dockerfile-cpu	Precompiles dependencies and source for CPU queue-based workers.
Dockerfile	Precompiles dependencies and source for GPU queue-based workers.

_{Review effort: Balanced}