CI: build images

[ijc]

Build a set of images from the cross of cross of KUBE_RUNTIME={docker,cri-containerd} and KUBE_NETWORK={weave,bridge}, build both BIOS and EFI images in all cases.

WIP while I play with the CI setup and understand the various interactions of workspaces, docker image cache, artifact publishing from multiple jobs etc.

The previous used of /workspace/images is switched to /workspace/packages to free up images for the VM images.

[ijc]

Hrm, 1 successful check (which is the dco check). Either Circle is having a hiccup or I've somehow managed to disable it...

[ijc]

Hrm, I buggered the syntax, so it errorred out but didn't say anything. Nifty.

The webpage says:

We weren't able to start this workflow.
The following jobs are unreachable: images
images: requires job "build-image-docker-bridge" but "build-image-docker-bridge" is not part of this workflow.
images: requires job "build-image-docker-weave" but "build-image-docker-weave" is not part of this workflow.
images: requires job "build-image-cri-containerd-weave" but "build-image-cri-containerd-weave" is not part of this workflow.
images: requires job "build-image-cri-containerd-bridge" but "build-image-cri-containerd-bridge" is not part of this workflow.
For more examples see the Workflows documentation.

That's something to watch for!

[ijc]

Previously the CI was taking 3-3½ minutes. So far in my iterations here it looks to be taking more like 7-10 minutes with parallelism of 4. We are building 4 packages followed by 4 images, so more parallelism seems unlikely to help much.

[ijc]

OK, I think this is about ready. I'll keep #9 open for now in case review requires retesting.

[ijc]

Some times observed during testing.

Package builds (in parallel up to 4):

Package	NOP (unchanged, pulled from hub)	Built
kubelet	02:52	11:18
kubernetes-docker-image-cache-common	00:51	01:30
kubernetes-docker-image-cache-control-plane	01:27	02:06
cri-containerd	00:31	02:10

I didn't do lots of measurements and there's some variance (mostly due to the network traffic I expect).

Image building, up to 4 in parallel, each depends on the relevant package builds:

↓ Runtime / Network →	Weave	Bridge
Docker	02:56	02:44
CRI	02:04	03:26

Again some variance.

Push to hub takes ~2:00 if it pushes both kubelet and cri-containerd and ~1:30 if it pushes neither (it still does a bunch of setup and imports the images even if there turns out to be nothing to push).

If all 4 packages need building then the elapsed time was around 24:30, without anything needing to be built was ~8:10, I expect this will vary depending on the scheduling of the parallel jobs and which packages have actually changed.

Without the parallelism I'd expect the full nop run to take ~20 mins and a full build more like ~30 mins so I think splitting into jobs like this is worthwhile.