Job / Task Scheduler — Notes
Functional
- Schedule jobs by cron or event.
- Dependencies / DAGs.
- Retries, SLAs, alerts.
- Backfill / rerun.
- Operator UI + API.
Non-functional
- Sub-minute scheduling precision.
- HA scheduler with leader election.
- Tens of thousands of concurrent task runs.
Trade-offs
- Airflow = batch + DAG-first; Temporal/Cadence = code-first long workflows; Argo = K8s-native.
- Pull workers vs push from scheduler: pull preferred for scale.
- At-least-once execution = task author MUST design idempotency.
Refs
- Apache Airflow docs; Temporal, Cadence; Argo Workflows.
- Google "Borg" paper (cluster scheduling cousin).
- Netflix Conductor docs.