This program performs a binary search to find the point at which we reach a layer limit when running
container images. It assumes you are able to run docker without root access (alternatively, you can
run the compiled binary using sudo ./target/release/layer-limit-calculator).
cargo run --release
The program crashes when using stock Docker, because the image builder fails due to the high number of layers. Consider configuring Docker to use containerd, which is also used by stock Kubernetes.
You could also write a program that generates images directly, without going through Docker, but we chose to use Dockerfiles here to keep things simple (even though it takes longer to run).
We were able to run a successful test with 260 layers, and suspect that the limit is even higher. However, at higher layer counts the Docker layer builder hits an internal error, so we couldn't test them. A possible workaround for this could be to build the images programmatically, in Rust code, instead of going through Docker.
Software versions:
$ docker --version
Docker version 26.1.2, build 211e74b
$ containerd --version
containerd containerd.io 1.6.31 e377cd56a71523140ca6ae87e30244719194a521