The article explains RocketMQ's two‑layer locking mechanism that guarantees ordered consumption by holding a queue‑level lock inside a while loop, clarifies why autoCommit only affects offset reporting, and shows how the client correctly processes multiple messages in a single thread.
The article investigates a MySQL deadlock that arises when multiple threads concurrently execute INSERT … ON DUPLICATE KEY UPDATE for logistics cancellations, reproduces the issue on MySQL 5.7 and 8.0, analyzes InnoDB lock handling and internal mini‑transactions, and explains how batch processing of each value leads to the deadlock.
This article explains how InnoDB determines whether a transaction already holds a table lock, acquires a mutex token, checks for blocking locks, and creates or reuses lock structures, detailing the complete table‑lock acquisition workflow in MySQL 8.0.32.
This article examines Yanxuan's inventory management challenges and presents a layered design—warehouse, physical, and sales layers—combined with a flexible lock‑stock pool to support multi‑channel, multi‑warehouse operations while addressing promotional and special‑use inventory requirements.
