> --cache-from
> Images to utilize as potential cache sources. Podman does not currently support caching so this is a NOOP.
On my local computer (Arch) podman is v2.1.1, which seems to have whatever bug I was hitting fixed.
So I guess my complaint isn't about podman specifically-- It had bugs and they were fixed, and that's great. But I hate that RHEL 8 touts it as a docker replacement, and won't carry docker in their repositories, when the version they have in their production releases is so broken.
We eventually sledgehammered docker CE's CentOS repo into our RHEL 8 jenkins server and now everything works perfectly.
Running podman on the production webservers seems to work okay though-- apart from the process killing problems.
You can get access to Moby in Fedora, but it just wasn't viable to include docker in RHEL 8 for both legal and community risks.
- Build layer cache doesn't seem to work. If I rebuild locally with podman, it correctly detects cache hits and the build is fast. On our Jenkins server (RHEL 8) with podman 2.0.5 it doesn't. It randomly doesn't cache hit, causing builds to take 20x longer than with docker CE.
- Podman is insanely slow at building images in general. COPY emptyfolder/ /emptyfolder/ takes 2 seconds. We have dozens of things to COPY and it's stupid slow compared to docker CE. Buildah doesn't seem any better.
- Systemd integration has bugs. If you use the default generated systemd unit file, it does not kill processes when exiting and leaves them dangling. Even after removing the strange KillMode=none it says to put in there, it still leaves processes dangling. Podman sometimes loses track of the container. It will list nothing in "podman ps" but the processes will still be running.