How 3 Million Reconnection Tests Prove smart-mqtt v1.2.0’s Stability

Version Overview

smart-mqtt v1.2.0 is released as the most lightweight MQTT broker in the Java ecosystem, targeting stable and efficient messaging.

Stability Verification

Near 3 million client disconnect‑reconnect cycles were executed over several days. In simulated high‑concurrency, frequent connect/disconnect scenarios, all metrics remained steady with no packet loss, service interruption, or abnormal resource growth.

Core Optimizations

Asynchronous batch consumption

New async batch mechanism ingests metric data into storage.

Reduces database write pressure and safeguards broker stability.

Smart resource management

Detects idle topics and releases associated memory.

H2 database defaults to file‑based persistence to avoid long‑run memory bloat.

Subscription structure refactor

Improves internal topic subscription design.

Boosts processing efficiency in large‑scale subscription scenarios.

Feature Enhancements & Bug Fixes

Fixed occasional MqttClient version loss.

Optimized retain‑message handling.

Improved console log output at startup.

Enhanced new‑version detection.

Upgraded reconnection logic in the stress‑test tool.

Dependency Slimming

Removed commons-lang and slf4j dependencies.

Resulting distribution is smaller and less prone to dependency conflicts.

Component Upgrades

feat → 1.1.0

smart-socket → 1.5.69

Acquisition

GitHub mirror: https://github.com/smartboot/smart-mqtt

Gitee main repository: https://gitee.com/smartboot/smart-mqtt

Quick Start (Docker)

docker run --name smart-mqtt \
  -p 18083:18083 \
  -p 1883:1883 \
  -d smartboot/smart-mqtt:latest

Web console: http://localhost:18083

MQTT port: 1883