Docker: statically link the C runtime

[julianbraha]

During testing, I measured a 1.5% speedup to zero-bin by statically linking the C runtime.

[0xaatif]

Thanks Julian! Could you share details of your test methodology?

[julianbraha]

No

[0xaatif]

I don't think we should fix the target like this - we have users on amd64 that this build needs to work for

Is this required for crt-static?

[julianbraha]

It's a good point, but yeah the target needs to be set explicitly for crt-static.

Maybe the target should be made an argument to the Dockerfile, instead?

[0xaatif]

I'm a bit skeptical of the changes as written:

• TARGET defaults to x86_64, so we break amd64 arm64 users immediately, and they have to override (every time!) it to get it working. This is not the UX I want for devs
• We ignore the rustflags in .config/cargo.toml, which leaves us open to this regression: fix: linkme lld issue in CI zero-bin#79 (I'm not sure if that specific issue still exists, but I want only one place for RUSTFLAGS in general)
• I don't have more details of the speedup

I like the Dockerfile as a quick way, general way for users to get started, and I think this performance improvement belongs elsewhere.

I think we have space for an optimised build job, which e.g

• only targets x86_64
• single-threads the compiler
• statically links the crt
• any linker shenanigans that help us

But I don't think that space is here - perhaps a bash script or even a doc for very performance-sensitive users - how do you feel about moving your suggestion to some documentation, for example?

[atanmarko]

@julianbraha I would agree with @0xaatif, that this Docker image's primary purpose is to be a quick starter for novel users of the project that should work out of the box. 1.5% speedup is not worth breaking up wider compatibility and usability in this particular case. But certainly, this optimization is good to know, and we should use it somewhere else.

[julianbraha]

TARGET defaults to x86_64, so we break amd64 users immediately, and they have to override (every time!) it to get it working. This is not the UX I want for devs

I think there's a misunderstanding here - the amd64 target for Rust is called x86_64.

this Docker image's primary purpose is to be a quick starter for novel users of the project that should work out of the box

I was thinking that anyone running this in a production environment would be using Docker/Kubernetes. But perhaps it would be better to split it into a "quickstart" Dockerfile and a high-optimization Dockerfile.

Feel free to close this.

[0xaatif]

I think there's a misunderstanding here - the amd64 target for Rust is called x86_64.

You're correct, I misspoke - I meant to write arm64 - I've updated my original message

I'll create an issue to track builds/docs for optimised users

[0xaatif]

#544