Think about building develop from time to time for ccache

[jpfeuffer]

Due to GHA restrictions, caches can only be pulled from target branches, default branch or the same branch.

This means PRs will only be able to get a cache from develop if they are made against develop (NOT from nightly).
There are no builds for develop currently.
Would be great if PRs start to build from a develop cache. Probably saves quite some time (20+ mins) for each initial build in a PR.

[jpfeuffer]

Any thoughts about that @timosachsenberg @poshul

[timosachsenberg]

Ah ok I see. How would you do that? E.g. in the nightly action? But what if one PR gets merged into develop? Does this invalidate the cache already? Sounds interesting but not sure if we have enough space for extra caches?

[jpfeuffer]

I think one wouldn't need the nightly cache anymore.
Starting from the first build on a PR, a PR has its own cache anyway so no problem if sth happens on Dev while the PR is open.
Does that answer the question?

[jpfeuffer]

The nightly action would need to build (additionally?) from develop though

[timosachsenberg]

This is how it works right now right?
https://github.com/OpenMS/OpenMS/blob/develop/.github/workflows/openms_ci_matrix_full.yml#L302-L311
Would you just replace "nightly" with "develop" in the full action then after #7493 is merged?
We can try that.

[jpfeuffer]

Basically yes. We would need to make sure that no logic depends on the name of the branch being nightly and instead maybe solely rely on the type of build trigger and workflow inputs.
We could even think about removing the nightly concept. It was mostly to be able to restart lengthy Jenkins pipelines with the same branch (name). If there is only one action to trigger to produce all the nightly artifacts, I think this is not so important anymore. If one wants to keep that functionality one could use a moving nightly tag, then you could start a manual workflow_dispatch on that tag.