Why Uber Engineering Switched from Postgres to MySQL

uber的分析

One of the core design aspects of Postgres is immutable row data. These immutable rows are called “tuples” in Postgres parlance. These tuples are uniquely identified by what Postgres calls a ctid. A ctid conceptually represents the on-disk location (i.e., physical disk offset) for a tuple. Multiple ctids can potentially describe a single row

pg的这个核心设计会导致一系列的问题, 核心指标上更 expensive.
1.写入放大
2.同步放大