系统表介绍
threads 每一行表示一个服务器线程
| 列名 | 含义 |
|---|---|
| THREAD_ID | 线程编号 |
| NAME | 线程名称 |
| TYPE | 线程类型 |
| PROCESSLIST_ID | 进程ID (同PROCESSLIST表) |
| PROCESSLIST_USER | 登录用户 |
| PROCESSLIST_HOST | 客户端IP |
| PROCESSLIST_DB | 默认数据库 |
| PROCESSLIST_COMMAND | 当前正在执行的命令类型 |
| PROCESSLIST_TIME | 当前状态的持续时间 |
| PROCESSLIST_STATE | 当前状态 |
| PROCESSLIST_INFO | 正在被执行的语句 |
| PARENT_THREAD_ID | 父线程编号 |
| ROLE | 未使用 |
| INSTRUMENTED | 是否被监测 |
| HISTORY | 是否记录线程历史信息 |
| CONNECTION_TYPE | 连接类型(本地为null,SSL/TLS,SOCKET,NAMED PIPE SHARED_MEMORY) |
| THREAD_OS_ID | 操作系统线程编号 |
实例
mysql> SELECT * FROM threads order by type desc limit 2 \G ;
*************************** 1. row ***************************
THREAD_ID: 26
NAME: thread/sql/compress_gtid_table
TYPE: FOREGROUND
PROCESSLIST_ID: 1
PROCESSLIST_USER: NULL
PROCESSLIST_HOST: NULL
PROCESSLIST_DB: NULL
PROCESSLIST_COMMAND: Daemon
PROCESSLIST_TIME: 12823255
PROCESSLIST_STATE: Suspending
PROCESSLIST_INFO: NULL
PARENT_THREAD_ID: 1
ROLE: NULL
INSTRUMENTED: YES
HISTORY: YES
CONNECTION_TYPE: NULL
THREAD_OS_ID: 2648
*************************** 2. row ***************************
THREAD_ID: 379
NAME: thread/sql/one_connection
TYPE: FOREGROUND
PROCESSLIST_ID: 354
PROCESSLIST_USER: dao
PROCESSLIST_HOST: 192.168.2.62
PROCESSLIST_DB: NULL
PROCESSLIST_COMMAND: Binlog Dump
PROCESSLIST_TIME: 254734
PROCESSLIST_STATE: Master has sent all binlog to slave; waiting for more updates
PROCESSLIST_INFO: SET @slave_uuid= '089a60e4-7972-11eb-9439-000c2904aaaa'
PARENT_THREAD_ID: NULL
ROLE: NULL
INSTRUMENTED: YES
HISTORY: YES
CONNECTION_TYPE: TCP/IP
THREAD_OS_ID: 3294
2 rows in set (0.00 sec)
关于thread_id ,查看MySQL服务进程的线程
[root@etlbi ~]# ps -T -p 2621
PID SPID TTY TIME CMD
2621 2621 ? 00:00:01 mysqld
2621 2622 ? 00:00:00 mysqld
2621 2623 ? 00:00:13 mysqld
2621 2624 ? 00:00:12 mysqld
2621 2625 ? 00:00:12 mysqld
2621 2626 ? 00:00:13 mysqld
2621 2627 ? 00:00:12 mysqld
2621 2628 ? 00:00:12 mysqld
2621 2629 ? 00:00:17 mysqld
2621 2630 ? 00:00:14 mysqld
2621 2631 ? 00:00:14 mysqld
2621 2632 ? 00:00:13 mysqld
2621 2633 ? 00:00:25 mysqld
2621 2635 ? 00:00:10 mysqld
2621 2636 ? 00:00:33 mysqld
2621 2637 ? 00:00:03 mysqld
2621 2638 ? 00:00:20 mysqld
2621 2639 ? 00:00:04 mysqld
2621 2640 ? 00:00:02 mysqld
2621 2641 ? 00:00:02 mysqld
2621 2642 ? 00:00:01 mysqld
2621 2643 ? 00:00:00 mysqld
2621 2644 ? 00:00:02 mysqld
2621 2645 ? 00:00:03 mysqld
2621 2646 ? 00:00:00 mysqld
2621 2647 ? 00:00:00 mysqld
2621 2648 ? 00:00:00 mysqld
2621 2886 ? 00:00:00 mysqld
2621 3026 ? 00:00:24 mysqld
2621 3027 ? 00:00:00 mysqld
2621 3028 ? 00:00:00 mysqld
2621 3029 ? 00:00:05 mysqld
2621 3030 ? 00:00:00 mysqld
2621 3031 ? 00:00:00 mysqld
2621 3032 ? 00:00:00 mysqld
2621 3033 ? 00:00:01 mysqld
2621 3034 ? 00:00:30 mysqld
2621 3035 ? 00:00:00 mysqld
2621 3281 ? 00:00:15 mysqld
2621 3282 ? 00:00:25 mysqld
2621 3288 ? 00:00:01 mysqld
2621 3290 ? 00:00:00 mysqld
2621 3294 ? 00:00:01 mysqld
2621 3295 ? 00:00:06 mysqld
2621 3299 ? 00:00:00 mysqld