Please consider to use the process based backend (default tracker) as it can spawn any process, i.e. also podman
Podman Tracker implements the JobTracker interface used by the Go DRMAA2 implementation in order to use Podman as a backend for managing jobs as containers.
A JobTemplate requires:
- JobCategory -> maps to a container image name
- RemoteCommand -> which is the command executed within the given container image
| DRMAA2 Job Control | Podman |
|---|---|
| Suspend | Pauses the container (does not work with rootless and cgroups v1 according to podman) |
| Resume | Continues a paused container |
| Terminate | Kills a running container |
| Hold | Unsupported |
| Release | Unsupported |
| DRMAA2 State | Podman State |
|---|---|
| Failed | Container is not "Restarting", "Paused", "Running" had has exit code != 0 |
| Done | Container is not "Restarting", "Paused", "Running", and has exit code 0 |
| Suspended | Container is paused (if supported) |
| Running | Container state is "Running" or "Restarting" (sets substate "restarting") |
| Queued | - |
| Undetermined | Container inspect fails |
DeleteJob equals podman rm and is removing an installed container. It must be terminated / finished before.
Mapping between the job template and the Podman container config is only implemented in the most minimalistic way. More to come.
| DRMAA2 JobTemplate | Podman Container Config Request |
|---|---|
| RemoteCommand | Cmd[0] |
| Args | Cmd[1:] |
| JobCategory | Image |
| CandidateMachines[0] | spec.Hostname (container's hostname) |
| WorkingDirectory | spec.WorkDir (working dir in the container, / if not set) |
| JobEnviornment | spec.Env |
| ExtensionList["user"] | spec.User (user in container) |
| ExtensionList["exposedPorts] | Port forwarding in format [hostip:]hostPort:containerPort,... / spec. |
| ExtensionList["privileged"] | spec.Privileged |
| ExtensionList["restart"] | spec.RestartPolicy / like "unless-stopped", default "no" / use with care |
| ExtensionList["ipc"] | spec.IpcNS namespace (default private) / like docker --ipc "host" |
| ExtensionList["uts"] | spec.UtsNS namespace (default private) / like docker --uts "host" |
| ExtensionList["pid"] | spec.PidNS namespace (default private) / like docker --pid "host" |
| ExtensionList["rm"] | --rm "true" or "TRUE" |
Since Array Jobs are not supported by Podman the job array functionality is implemented by creating n tasks sequentially in a loop. The array job ID contains all IDs of the created Podman containers.