Time calculation

Aikesheng Open Source Community

Dec 3, 2019 · Databases

Understanding How MySQL SHOW PROCESSLIST Calculates the Time Column and Why Negative Values Appear

This article explains the internal calculation of the Time column shown by MySQL's SHOW PROCESSLIST command, covering the source functions, overloads of THD::set_time, various scenarios that affect the result—including replication lag, manual timestamp settings, and idle sessions—and why Percona and official builds may display different values.