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  • Published on
    This article compares WeScale, a MySQL-compatible database proxy, with MySQL, highlighting its read-write splitting, connection pooling, and failover features. WeScale maintains high throughput and low latency under heavy loads, with minimal additional memory use and about 1/3 CPU overhead. It scales better both horizontally and cost-effectively than scaling MySQL vertically.
  • Published on
    Database schema evolution (DDL) poses unique challenges in ensuring concurrency with transactions while maintaining ACID properties. Traditional approaches use metadata locks (MDLs) to serialize DDL and DML/DQL, but this can severely impact performance. This blog discusses the issues and explores solutions like multi-version concurrency control to enable highly concurrent non-blocking schema changes.
  • Published on
    This blog discusses the fatal problem of distributed metadata lock (MDL) deadlocks that can occur when distributed transactions and database definition language (DDL) statements execute concurrently across multiple database nodes. It explains the causes and presents a solution for detecting these distributed MDL deadlocks.