gh-146197: Add Emscripten to CI

[hoodmane]

Time:

• 19m 28s without cache
• 17m 8s with cache

By comparison, the build bot took 32m 8s with cache. I guess the github action runners are quite a bit faster than the instance running the build bot.

• Issue: Add CI job for Emscripten #146197

[webknjaz]

Looks great at glance! Does it need an entire hour to complete though? If not, I'd make the timeout smaller.

[hoodmane]

I just copied the timeout-minutes: 60 from reusable-wasi which doesn't need 60 minutes either.

[hoodmane]

!buildbot emscripten

[bedevere-bot]

🤖 New build scheduled with the buildbot fleet by @hoodmane for commit 9da3ed3 🤖

Results will be shown at:

https://buildbot.python.org/all/#/grid?branch=refs%2Fpull%2F146198%2Fmerge

The command will test the builders whose names match following regular expression: emscripten

The builders matched are:

• WASM Emscripten PR

[hoodmane]

So it took 19m 28s with no cache. But the cache is not working yet.

[hoodmane]

!buildbot emscripten

[bedevere-bot]

🤖 New build scheduled with the buildbot fleet by @hoodmane for commit d77a339 🤖

Results will be shown at:

https://buildbot.python.org/all/#/grid?branch=refs%2Fpull%2F146198%2Fmerge

The command will test the builders whose names match following regular expression: emscripten

The builders matched are:

• WASM Emscripten PR

[hoodmane]

!buildbot Emscripten

[bedevere-bot]

🤖 New build scheduled with the buildbot fleet by @hoodmane for commit 4276a51 🤖

Results will be shown at:

https://buildbot.python.org/all/#/grid?branch=refs%2Fpull%2F146198%2Fmerge

The command will test the builders whose names match following regular expression: Emscripten

The builders matched are:

• WASM Emscripten PR

[hoodmane]

!buildbot Emscripten

[bedevere-bot]

🤖 New build scheduled with the buildbot fleet by @hoodmane for commit 4276a51 🤖

Results will be shown at:

https://buildbot.python.org/all/#/grid?branch=refs%2Fpull%2F146198%2Fmerge

The command will test the builders whose names match following regular expression: Emscripten

The builders matched are:

• WASM Emscripten PR

[hoodmane]

!buildbot emscripten

[bedevere-bot]

🤖 New build scheduled with the buildbot fleet by @hoodmane for commit 1520ee8 🤖

Results will be shown at:

https://buildbot.python.org/all/#/grid?branch=refs%2Fpull%2F146198%2Fmerge

The command will test the builders whose names match following regular expression: emscripten

The builders matched are:

• WASM Emscripten PR

[hugovk]

Emscripten is (currently) tier 3, so should we allow PRs to be merged when this fails?

Although in practice, people generally don't like merging red PRs, which is good. And testing here on GHA can help later promote to a higher tier, when we wouldn't allow failures.

[hugovk]

0:00:00 load avg: 0.10 Run 501 tests sequentially in a single process

Is it required to run sequentially?

Although it can help to have some sequential CI, and there's slower jobs than this one so it won't be the bottleneck.

[hoodmane]

Is it required to run sequentially?

We don't have any threads or process support so I think so.

[hugovk]

Thanks!

[hoodmane]

!buildbot emscripten

[bedevere-bot]

🤖 New build scheduled with the buildbot fleet by @hoodmane for commit 9d545d1 🤖

Results will be shown at:

https://buildbot.python.org/all/#/grid?branch=refs%2Fpull%2F146198%2Fmerge

The command will test the builders whose names match following regular expression: emscripten

The builders matched are:

• WASM Emscripten PR

[webknjaz]

Alright, let's set the timeout to 25-30 minutes — this will help catch problems early. We just need to cover the cacheless run, plus have some margin for networking + minor flakiness. Otherwise, situations with something getting stuck for 40min+ would waste CI resources..

[hoodmane]

Well we have:

  1 job  with timeout-minutes: 30
  5 jobs with timeout-minutes: 5
  8 jobs with timeout-minutes: 10
 26 jobs with timeout-minutes: 60

Since most other CI jobs seem to have timeout-minutes: 60 I'd prefer to just keep the setting here as for the rest and then lowering these timeouts can be dealt with systematically as a separate issue.