long rerenders

[beckermr]

The autotick bot is hitting rerenders that run over 10 minutes. This is wrong. We don't have an example yet, but the last one was the ambertools feedstock.

[xhochy]

arrow-cpp is not taking 10min but is generally quite heavy on the rerendering lengths if you need an example.

[scopatz]

maybe it is time to try to use mamba in conda-smithy?

[wolfv]

I am going to start working on "mamba-build" (will be called boa) this week. If anyone wants to collaborate, let me know!

[xhochy]

There are two different performance hotspots in conda-smithy for the arrow-cpp rerender:

• Downloading the repodata.json and checking whether we use the latest smithy version, here mamba can help.
• Rendering the CI templates, here we call out to conda_build.api.render, this is where a mamba-build could help.

[xhochy]

Rendering the CI templates also can be done in parallel as we're rendering multiple templates. Still I would first tackle the version check as the return-on-invest is much higher.

[saraedum]

Rerendering is also very slow for me when using source.git_url. This can be fixed by passing dirty=True to the cond_build.api.render() but I am not sure what the possible negative impact of that might be.

[timsnyder]

I'm getting really tired of waiting on the 30 minute ctng-compilers-feedstock rerenders. If no one has looked into using boa for rerender, I might give it a whirl while I'm waiting. I'm thinking by now, there must be a way to just install things and smithy picks up the monekypatched conda-build, right?

[beckermr]

I don't think it is purely boa. I think there are optimizations needed in conda build itself.

[jakirkham]

Would actually suggest trying the new libmamba Conda solver. Can just add this to condarc to enable it.

experimental_solver: libmamba

Then would try re-rendering as usual.

It's possible there's more things needed to get that working, but that's probably a good starting point.

[wolfv]

here is a draft PR for conda mambarender ... functionality: https://github.com/mamba-org/boa/pull/271

However, I don't know what and how to print.

[jakirkham]

Raised a webservice issue about using libmamba ( https://github.com/conda-forge/conda-forge-webservices/issues/502 )

[leofang]

nvcc takes 40-50 mins to rerender.

[jakirkham]

Leo, if you have a moment, it would be interesting to try re-rendering with the libmamba solver to see if that helps ( https://github.com/conda-forge/conda-smithy/issues/1307#issuecomment-1082942123 ) and if the results differ in any notable way.