show processlist time负数的初探
作者简介：高鹏，笔名八怪。《深入理解MySQL主从原理》图书作者，同时运营个人公众号“MySQL学习”，持续分享遇到的有趣case以及代码解析！
本文主要解释一下下面两个语句的相应接口和时间计算方式。
- select * from information_schema.processlist;
- show processlist
一、show processlist
函数接口：mysqld_list_processes
栈帧：
#0 mysqld_list_processes (thd=0x7ffedc008250, user=0x0, verbose=false) at /mysqldata/percona-server-locks-detail-5.7.22/sql/sql_show.cc:2370
#1 0x00000000015ccaab in mysql_execute_command (thd=0x7ffedc008250, first_level=true) at /mysqldata/percona-server-locks-detail-5.7.22/sql/sql_parse.cc:3789
#2 0x00000000015d2fde in mysql_parse (thd=0x7ffedc008250, parser_state=0x7fffec5bd600) at /mysqldata/percona-server-locks-detail-5.7.22/sql/sql_parse.cc:5901
#3 0x00000000015c6b72 in dispatch_command (thd=0x7ffedc008250, com_data=0x7fffec5bdd70, command=COM_QUERY)
at /mysqldata/percona-server-locks-detail-5.7.22/sql/sql_parse.cc:1490
#4 0x00000000015c58ff in do_command (thd=0x7ffedc008250) at /mysqldata/percona-server-locks-detail-5.7.22/sql/sql_parse.cc:1021
#5 0x000000000170e578 in handle_connection (arg=0x5f4fe40) at /mysqldata/percona-server-locks-detail-5.7.22/sql/conn_handler/connection_handler_per_thread.cc:312
#6 0x0000000001945538 in pfs_spawn_thread (arg=0x6809be0) at /mysqldata/percona-server-locks-detail-5.7.22/storage/perfschema/pfs.cc:2190
#7 0x00007ffff7bcfaa1 in start_thread () from /lib64/libpthread.so.0
#8 0x00007ffff6b37c4d in clone () from /lib64/libc.so.6
