* tests: Ensure excessive FD limits are avoided
Processes that run as daemons (`postsrsd` and `fail2ban-server`) initialize by closing all FDs (File Descriptors).
This behaviour queries that maximum limit and iterates through the entire range even if only a few FDs are open. In some environments (Docker, limit configured by distro) this can be a range exceeding 1 billion (from kernel default of 1024 soft, 4096 hard), causing an 8 minute delay with heavy CPU activity.
`postsrsd` has since been updated to use `close_range()` syscall, and `fail2ban` will now iterate through `/proc/self/fd` (open FDs) which should resolve the performance hit. Until those updates reach our Docker image, we need to workaround it with `--ulimit` option.
NOTE: If `docker.service` on a distro sets `LimitNOFILE=` to approx 1 million or lower, it should not be an issue. On distros such as Fedora 36, it is `LimitNOFILE=infinity` (approx 1 billion) that causes excessive delays.
* chore: Use Docker host limits instead
Typically on modern distros with systemd, this should equate to 1024 (soft) and 512K (hard) limits. A distro may override the built-in global defaults systemd sets via setting `DefaultLimitNOFILE=` in `/etc/systemd/user.conf` and `/etc/systemd/system.conf`.
* tests(fix): Better prevent non-deterministic failures
- `no_containers.bats` tests the external script `setup.sh` (without `-c`). It's expected that no existing DMS container is running - otherwise it may attempt to use that container and fail. Detect this and fail early via `setup_file()` step.
- `mail_hostname.bats` had a odd timing failure with teardown due to the last tests bringing the containers down earlier (`docker stop` paired with the `docker run --rm`). Adding a moment of delay via `sleep` helps avoid that false positive scenario.
* docker_container first, then fall back to docker_image
+ test changes to support
+ test change to wait for smtp port to fix flakey tests since https://github.com/docker-mailserver/docker-mailserver/pull/2104
* quick fix
* Update setup.sh
Co-authored-by: Georg Lauterbach <44545919+georglauterbach@users.noreply.github.com>
Co-authored-by: Casper <casperklein@users.noreply.github.com>
