Achieving End-to-End Exactly-Once Semantics in Apache Flink with Apache Kafka

Two-Phase Commit in Flink Sink Operators Flink achieves exactly-once guarantees for external systems through an implementation of the Two-Phase Commit (2PC) protocol. The core mechanism aligns transaction boundaries with checkpoint barriers. When a sink operator receives the first record of a checkpoint interval or encounters a checkpoint barri ...

Posted on Sat, 13 Jun 2026 17:01:31 +0000 by mj99

Key Features and Enhancements in Apache Flink 1.14 to 1.17

Apache Flink 1.14.0 Highlights Core Features Checkpointing for Bounded Streams. Mixed DataStream and Table/SQL Applications in Batch Execution Mode. Introduction of the Hybrid Source for seamless reading across multiple sources. Buffer Debloating to minimize checkpoint latency. Fine-Grained Resource Management for dynamic Slot sizing. New Puls ...

Posted on Thu, 07 May 2026 19:17:24 +0000 by kade119

Apache Flink Checkpoint Configuration Guide

Prerequisites Exactly Once Processing For exactly once semantics to work properly: Source systems: Must support data retransmission (e.g., message queues like Kafka, distributed file systems like HDFS) Sink systems: Must support idempotent operations (e.g., Doris supports deduplication) At Least Once Processing For at least once semantics: S ...

Posted on Thu, 07 May 2026 06:14:41 +0000 by smpdawg