This article explores RocketMQ's high availability mechanism, focusing on DLedger's implementation of Raft-based leader election for distributed message middleware, covering both traditional and Controller mode architectures.
This article examines RocketMQ's high‑availability evolution—from early master‑slave and Raft‑based designs to the v5 DLedger fusion model—detailing replica groups, data sharding, election mechanisms, replication strategies, metric trade‑offs, log‑divergence handling, controller roles, heartbeat optimizations, and comparisons with Kafka and Pulsar, all illustrated with diagrams and code snippets.
Apache RocketMQ 4.8.0 introduces extensive DLedger enhancements, including asynchronous pipeline processing, batch log replication, extensive chaos‑testing validation, preferred‑leader selection, and batch‑message support, delivering several‑fold throughput improvements, faster recovery from failures, and new functional capabilities for production‑grade messaging.
Apache RocketMQ 4.8.0 has been released, featuring extensive optimizations and bug fixes, with significant performance, functionality, and stability enhancements to the Raft‑based DLedger mode, including asynchronous pipeline processing, batch log replication, and various lock and cache improvements that boost throughput by multiple times.
This article explains how to build a highly available, high‑throughput, and horizontally scalable RocketMQ cluster by deploying multiple NameServers and using the Dledger mode to achieve fault‑tolerance, load distribution, and massive message handling for demanding business scenarios.
