show full processlist;
//列出当前的操作process，看到很多处于waiting的process，说明已经有卡住的proces。
这里我们看到是sending data的这条语句卡住了mysql
再执行：
kill processid;
kill 1693651;
//processid表示process的id，比如kill 3301，就会将id为3301的process杀死。
+---------+----------------------+-----------------+-------+------------------+---------+---------------------------------------------------------------+------------------------------------------------------------------------+-------------+----------------------+-----------+ | Id | User | Host | db | Command | Time | State | Info | Memory_used | Memory_used_by_query | CPU_time | +---------+----------------------+-----------------+-------+------------------+---------+---------------------------------------------------------------+------------------------------------------------------------------------+-------------+----------------------+-----------+ | 28 | rdsRepl | localhost:51284 | NULL | Binlog Dump GTID | 1220403 | Master has sent all binlog to slave; waiting for more updates | NULL | 18117 | 8208 | 239225 | | 1676492 | root | localhost:9183 | sync | Sleep | 5394 | | NULL | 895362 | 8208 | 32741806 | | 1688104 | root | localhost:11900 | sync | Sleep | 3766 | | NULL | 268480 | 8208 | 155952228 | | 1689762 | root | localhost:12057 | xtemp | Query | 1116 | Waiting for table metadata lock | SHOW TABLE STATUS | 813027 | 11024 | 5439530 | | 1690466 | root | localhost:12632 | xtemp | Query | 950 | Waiting for table metadata lock | SELECT TABLE_NAME, CHECK_OPTION, IS_UPDATABLE, SECURITY_TYPE, DEFINER | 114628 | 9776 | 5811522 | | 1693651 | root | localhost:14234 | sync | Query | 1338 | Sending data | CREATE TABLE xtemp.yxy_transfer AS SELECT c_date, SUM(is_reg) AS cnt_ | 1338135 | 15384 | 2542049 | | 1693702 | root | localhost:14342 | sync | Query | 1302 | Waiting for table metadata lock | DROP TABLE IF EXISTS xtemp.yxy_transfer | 17149 | 8208 | 2428293 | | 1694006 | root | localhost:14584 | sync | Query | 1085 | Waiting for table metadata lock | DROP TABLE IF EXISTS xtemp.yxy_transfer | 17149 | 8208 | 2397726 | | 1694108 | root | localhost:14594 | xtemp | Query | 936 | Waiting for table metadata lock | show create table xtemp.yxy_transfer | 37856 | 8208 | 953411 | | 1694417 | root | localhost:14771 | xtemp | Query | 762 | Waiting for table metadata lock | SELECT TABLE_NAME, CHECK_OPTION, IS_UPDATABLE, SECURITY_TYPE, DEFINER | 111067 | 9776 | 892068 | | 1694515 | root | localhost:14869 | xtemp | Query | 683 | Waiting for table metadata lock | SELECT TABLE_NAME, CHECK_OPTION, IS_UPDATABLE, SECURITY_TYPE, DEFINER | 127905 | 9776 | 831436 | | 1694540 | root | localhost:14875 | xtemp | Query | 651 | Waiting for table metadata lock | DROP TABLE IF EXISTS xtemp.yxy_transfer | 16638 | 8208 | 138945 | | 1694650 | root | localhost:1032 | xtemp | Query | 572 | Waiting for table metadata lock | SELECT TABLE_NAME, CHECK_OPTION, IS_UPDATABLE, SECURITY_TYPE, DEFINER | 117220 | 9776 | 937266 | | 1694666 | root | localhost:1033 | xtemp | Query | 0 | starting | show full processlist | 16470 | 8208 | 973631 | | 1695318 | unauthenticated user | connecting host | NULL | Connect | 0 | login | NULL | 0 | 0 | 0 | +---------+----------------------+-----------------+-------+------------------+---------+---------------------------------------------------------------+------------------------------------------------------------------------+-------------+----------------------+-----------+ 15 rows in set (0.14 sec)
+---------+---------+------+-------+------------------+---------+---------------------------------------------------------------+-----------------------+-------------+----------------------+-----------+ | Id | User | Host | db | Command | Time | State | Info | Memory_used | Memory_used_by_query | CPU_time | +---------+---------+------+-------+------------------+---------+---------------------------------------------------------------+-----------------------+-------------+----------------------+-----------+ | 28 | rdsRepl |xxx | NULL | Binlog Dump GTID | 1220453 | Master has sent all binlog to slave; waiting for more updates | NULL | 18117 | 8208 | 239225 | | 1676492 | root |xxx | sync | Sleep | 5444 | | NULL | 895362 | 8208 | 32741806 | | 1688104 | root |xxx | sync | Sleep | 3816 | | NULL | 268480 | 8208 | 155952228 | | 1689762 | root |xxx | xtemp | Sleep | 1166 | | NULL | 428709 | 8208 | 6319722 | | 1690466 | root |xxx | xtemp | Sleep | 1000 | | NULL | 20046 | 8208 | 6517271 | | 1694108 | root |xxx | xtemp | Sleep | 986 | | NULL | 39912 | 8208 | 1055550 | | 1694417 | root |xxx | xtemp | Sleep | 812 | | NULL | 16485 | 8208 | 1390755 | | 1694515 | root |xxx | xtemp | Sleep | 733 | | NULL | 27155 | 8208 | 1320086 | | 1694540 | root |xxx | xtemp | Sleep | 701 | | NULL | 85811 | 8208 | 16689270 | | 1694650 | root |xxx | xtemp | Sleep | 622 | | NULL | 16470 | 8208 | 1428922 | | 1694666 | root |xxx | xtemp | Query | 0 | starting | show full processlist | 16470 | 8208 | 1351151 | +---------+---------+------+-------+------------------+---------+---------------------------------------------------------------+-----------------------+-------------+----------------------+-----------+