Priority Queues in Distributed Systems

Concepts: pyKafkaPriority, pyFlinkTimers, pyCAPTheorem

In a single process, a heap is the priority queue. In a distributed system, maintaining a global priority order across multiple machines is a fundamentally different problem with CAP theorem implications. Kafka, Flink, and other distributed systems have specific, principled answers to how they handle priority ordering. Knowing these answers, and being able to articulate the CAP tradeoffs, is what separates a senior DE who 'has used Kafka' from a staff-level candidate who understands what Kafka can and cannot guarantee. Kafka: Per-Partition Priority, Not Global Priority Kafka does not implement a global priority queue. Kafka partitions are append-only logs. Within a partition, order is guaranteed (offset-based). Across partitions, there is no global ordering guarantee. If you need priority-