How do I kill all the processes in Mysql “show processlist”?

Question

Because I see a lot of processes there, and the \"time\" column shows big values for all of them.

Answer 1

Only for mariaDB

It doesn't get simpler then this, Just execute this in mysql prompt.

kill USER username;

It will kill all process under provided username. because most of the people use same user for all purpose, it works!

I have tested this on MariaDB not sure about mysql.

Answer 2

The following will create a simple stored procedure that uses a cursor to kill all processes one by one except for the process currently being used:

DROP PROCEDURE IF EXISTS kill_other_processes;

DELIMITER $$

CREATE PROCEDURE kill_other_processes()
BEGIN
  DECLARE finished INT DEFAULT 0;
  DECLARE proc_id INT;
  DECLARE proc_id_cursor CURSOR FOR SELECT id FROM information_schema.processlist;
  DECLARE CONTINUE HANDLER FOR NOT FOUND SET finished = 1;

  OPEN proc_id_cursor;
  proc_id_cursor_loop: LOOP
    FETCH proc_id_cursor INTO proc_id;

    IF finished = 1 THEN 
      LEAVE proc_id_cursor_loop;
    END IF;

    IF proc_id <> CONNECTION_ID() THEN
      KILL proc_id;
    END IF;

  END LOOP proc_id_cursor_loop;
  CLOSE proc_id_cursor;
END$$

DELIMITER ;

It can be run with SELECTs to show the processes before and after as follows:

SELECT * FROM information_schema.processlist;
CALL kill_other_processes();
SELECT * FROM information_schema.processlist;

Answer 3

If you don't have information_schema:

mysql -e "show full processlist" | cut -f1 | sed -e 's/^/kill /' | sed -e 's/$/;/' ;  > /tmp/kill.txt
mysql> . /tmp/kill.txt

Answer 4

If you are using laravel then this is for you:

$query = "SHOW FULL PROCESSLIST";
    $results = DB::select(DB::raw($query));

    foreach($results as $result){
        if($result->Command == "Sleep"){
            $sql="KILL ". $result->Id;
            DB::select(DB::raw($sql));
        }
    }

Of-course, you should use this use Illuminate\Support\Facades\DB; after your namespace.

Answer 5

I recently needed to do this and I came up with this

-- GROUP_CONCAT turns all the rows into 1
-- @q:= stores all the kill commands to a variable
select @q:=GROUP_CONCAT(CONCAT('KILL ',ID) SEPARATOR ';')  
FROM information_schema.processlist 
-- If you don't need it, you can remove the WHERE command altogether
WHERE user = 'user';
-- Creates statement and execute it
PREPARE stmt FROM @q;
EXECUTE stmt;
DEALLOCATE PREPARE stmt;

That way, you don't need to store to file and run all queries with a single command.

Answer 6

Sometimes I have some zombies mysql processes that can't be killed (using MAMP Pro).

First get a list of all mysql processes:

ps -ax | grep mysql

Next kill every one of them with (replace processId with the first column in previous command result):

kill -9 processId