[App] Add support for running with multiprocessing in the cloud #16624

ethanwharris · 2023-02-03T12:08:28Z

What does this PR do?

In the cloud we will set the host and number of exposed ports (starting at 7501). This PR makes changes so that, when those variables are set, we allocate ports sequentially from 7501 without collisions. If the app needs more ports than the number of exposed ports, we raise an error.

This also fixes a potential very rare bug where multiple requests to find_free_network_port could get the same port if it isn't being actively used yet. If somehow we fail 10 times to get a free port then an error will be raised to prevent an infinite loop.

Does your PR introduce any breaking changes? If yes, please list them.

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github-actions · 2023-02-03T12:09:02Z

⚡ Required checks status: All passing 🟢

Groups summary

🟢 lightning_app: Tests workflow

Check ID	Status
app-pytest (macOS-11, lightning, 3.8, latest)	success	✅
app-pytest (macOS-11, lightning, 3.8, oldest)	success	✅
app-pytest (macOS-11, app, 3.9, latest)	success	✅
app-pytest (ubuntu-20.04, lightning, 3.8, latest)	success	✅
app-pytest (ubuntu-20.04, lightning, 3.8, oldest)	success	✅
app-pytest (ubuntu-20.04, app, 3.9, latest)	success	✅
app-pytest (windows-2022, lightning, 3.8, latest)	success	✅
app-pytest (windows-2022, lightning, 3.8, oldest)	success	✅
app-pytest (windows-2022, app, 3.8, latest)	success	✅

These checks are required after the changes to src/lightning/app/core/constants.py, src/lightning/app/runners/backends/mp_process.py, src/lightning/app/runners/multiprocess.py, src/lightning/app/utilities/network.py, src/lightning/app/utilities/proxies.py, tests/tests_app/conftest.py, tests/tests_app/utilities/test_network.py, tests/tests_app/utilities/test_proxies.py.

🟢 lightning_app: Examples

Check ID	Status
app-examples (macOS-11, lightning, 3.9, latest)	success	✅
app-examples (macOS-11, lightning, 3.9, oldest)	success	✅
app-examples (macOS-11, app, 3.9, latest)	success	✅
app-examples (ubuntu-20.04, lightning, 3.9, latest)	success	✅
app-examples (ubuntu-20.04, lightning, 3.9, oldest)	success	✅
app-examples (ubuntu-20.04, app, 3.9, latest)	success	✅
app-examples (windows-2022, lightning, 3.9, latest)	success	✅
app-examples (windows-2022, lightning, 3.9, oldest)	success	✅
app-examples (windows-2022, app, 3.9, latest)	success	✅