cross-compile container images

[ereslibre]

Create multi-arch container images by first cross compiling the
binaries for the different platforms, and then creating the container
images by copying the binaries.

[ereslibre]

Converting to draft because of the usage of musl.cc.

[flavio]

Cool stuff 👏

[viccuad]

Thanks for this, this is great! I'm amazed that the compilation time went down to 15 minutes.

Did we talk about performance of running code already? I have read that Musl is not as efficient as libc on mem allocation. I suppose not a problem for our usage, but maybe worth checking.

With this, we will be moving our targets from Rust Tier 1 (guaranteed to work) to Tier 2 (guaranteed to build). For x86_64 this means a reduction in assurances. I suppose it's not a problem, but something to also have in mind.

[viccuad]

LGTM! yay!
Do we want to cross-compile on development too?
I tried here cargo build --target x86_64-unknown-linux-musl and it failed on the ring issue, so from what I understand it's not using .cargo/config.

[flavio]

Overall great 👏

I left some comments here and there

[flavio]

Same here

[flavio]

Do we want to cross-compile on development too? I tried here cargo build --target x86_64-unknown-linux-musl and it failed on the ring issue, so from what I understand it's not using .cargo/config.

Actually that would be nice, just to be able to reproduce bugs locally...

[ereslibre]

Do we want to cross-compile on development too? I tried here cargo build --target x86_64-unknown-linux-musl and it failed on the ring issue, so from what I understand it's not using .cargo/config.

Actually that would be nice, just to be able to reproduce bugs locally...

I also agree. I think is a good strategy. I would push for that right after this work. We can discuss about it. My preferred mechanism would be to have this as a nix project, so our dependencies are pinned and easily built (no need to fill pre-requirements prior to build other than having nix installed).

I think is worth checking, let me know if that's good with you and if you think we should plan for that soon.

[ereslibre]

Do we want to cross-compile on development too?

You can manually do this already, but is not pretty. Let me know if this fixes the build & link issue for you.

$ curl https://musl.cc/x86_64-linux-musl-cross.tgz | tar -xz
$ export PATH=$PWD/x86_64-linux-musl-cross/bin:$PATH
$ cargo build --target x86_64-unknown-linux-musl

Same for targeting aarch64 from x86_64:

$ curl https://musl.cc/aarch64-linux-musl-cross.tgz | tar -xz
$ export PATH=$PWD/aarch64-linux-musl-cross/bin:$PATH
$ cargo build --target aarch64-unknown-linux-musl

This should work AFAICT.

[flavio]

I think there's still some work going on, am I right? This doesn't look ready to be merged

[ereslibre]

I think there's still some work going on, am I right? This doesn't look ready to be merged

This is mergeable. I was testing GitHub behaviors when building the container image. Certain parts are a bit of trial and error. It's good now.

[jvanz]

LGTM! :D

[flavio]

Great, go ahead with it 👏