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

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

Mass killing operation saves time. Do it in MySql itself:

Run these commands

mysql> select concat('KILL ',id,';') from information_schema.processlist
where user='root' and time > 200 into outfile '/tmp/a.txt';

mysql> source /tmp/a.txt;

Reference

---------edit------------

if you do not want to store in file, store in a variable

Just run in your command prompt

> out1=$(mysql -B test -uroot -proot --disable-column-names  -e "select concat('KILL ',id,';') from information_schema.processlist where user='root' and time > 200;")

> out2= $(mysql -B test -uroot -proot --disable-column-names  -e "$out1")

You need to kill them one by one, MySQL does not have any massive kill command. You can script it in any language, for example in PHP you can use something like:

$result = mysql_query("SHOW FULL PROCESSLIST");
while ($row=mysql_fetch_array($result)) {
  $process_id=$row["Id"];
  if ($row["Time"] > 200 ) {
    $sql="KILL $process_id";
    mysql_query($sql);
  }
}

I have also searched how to parse through MySQL the command SHOW PROCESSLIST and ended with a one-liner in a Shell:

mysqladmin processlist -u <USERNAME> -p<PASSWORD> | \
awk '$2 ~ /^[0-9]/ {print "KILL "$2";"}' | \
mysql -u <USERNAME> -p<PASSWORD>

• mysqladmin processlist will print a table with the thread ids;
• awk will parse from the second column only the numbers (thread ids) and generate MySQL KILL commands;
• and finally the last call to mysql will execute the passed commands.

You can run grep before the awk command to filter a particular database name.

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.

Or... in shell...

service mysql restart

Yeah, I know, I'm lazy, but it can be handy too.

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.

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;

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

KILL ALL SELECT QUERIES

select concat('KILL ',id,';') 
from information_schema.processlist 
where user='root' 
  and INFO like 'SELECT%' into outfile '/tmp/a.txt'; 
source /tmp/a.txt;

This snipped worked for me (MySQL server 5.5) to kill all MySQL processes :

mysql -e "show full processlist;" -ss | awk '{print "KILL "$1";"}'| mysql

We can do it by MySQL Workbench. Just execute this:

kill id;

Example:

kill 13412

That will remove it.

I'd combine bash and mysql:

for i in $(mysql -Ne "select id from information_schema.processlist where user like 'foo%user' and time > 300;"); do
  mysql -e "kill ${i}"
done

Here is a solution that you can execute without relying on the operating system:

STEP 1: Create a stored procedure.

DROP PROCEDURE IF EXISTS  kill_user_processes$$ 

CREATE PROCEDURE `kill_user_processes`(
  IN user_to_kill VARCHAR(255)
)
READS SQL DATA
BEGIN

  DECLARE name_val VARCHAR(255);
  DECLARE no_more_rows BOOLEAN;
  DECLARE loop_cntr INT DEFAULT 0;
  DECLARE num_rows INT DEFAULT 0;

  DECLARE friends_cur CURSOR FOR
    SELECT CONCAT('KILL ',id,';') FROM information_schema.processlist WHERE USER=user_to_kill;

  DECLARE CONTINUE HANDLER FOR NOT FOUND
    SET no_more_rows = TRUE;

  OPEN friends_cur;
  SELECT FOUND_ROWS() INTO num_rows;

  the_loop: LOOP

    FETCH  friends_cur
    INTO   name_val;

    IF no_more_rows THEN
        CLOSE friends_cur;
        LEAVE the_loop;
    END IF;


 SET @s = name_val;
    PREPARE stmt FROM @s;
    EXECUTE stmt;
    DEALLOCATE PREPARE stmt;

    SELECT name_val;

    SET loop_cntr = loop_cntr + 1;

  END LOOP the_loop;

  SELECT num_rows, loop_cntr;

END $$
DELIMITER ;

STEP 2: Call the stored procedure giving it the name of a database user whose processes you want to kill. You could rewrite the stored procedure to filter on some other criteria if you like.

CALL kill_user_processes('devdba');

mysqladmin pr -u 'USERNAME' -p'PASSWORD' | awk '$2~/^[0-9]+/{print $2}' | xargs -i mysqladmin -u 'USERNAME' -p'PASSWORD' kill {}

login to Mysql as admin:

 mysql -uroot -ppassword;

And than run command:

mysql> show processlist;

You will get something like below :

+----+-------------+--------------------+----------+---------+------+-------+------------------+
| Id | User        | Host               | db       | Command | Time | State | Info             |
+----+-------------+--------------------+----------+---------+------+-------+------------------+
| 49 | application | 192.168.44.1:51718 | XXXXXXXX | Sleep   |  183 |       | NULL             ||
| 55 | application | 192.168.44.1:51769 | XXXXXXXX | Sleep   |  148 |       | NULL             |
| 56 | application | 192.168.44.1:51770 | XXXXXXXX | Sleep   |  148 |       | NULL             |
| 57 | application | 192.168.44.1:51771 | XXXXXXXX | Sleep   |  148 |       | NULL             |
| 58 | application | 192.168.44.1:51968 | XXXXXXXX | Sleep   |   11 |       | NULL             |
| 59 | root        | localhost          | NULL     | Query   |    0 | NULL  | show processlist |
+----+-------------+--------------------+----------+---------+------+-------+------------------+

You will see complete details of different connections. Now you can kill the sleeping connection as below:

mysql> kill 52;
Query OK, 0 rows affected (0.00 sec)

for python language, you can do like this

import pymysql

connection = pymysql.connect(host='localhost',
                             user='root',
                             db='mysql',
                             cursorclass=pymysql.cursors.DictCursor)

with connection.cursor() as cursor:
    cursor.execute('SHOW PROCESSLIST')
    for item in cursor.fetchall():
        if item.get('Time') > 200:
            _id = item.get('Id')
            print('kill %s' % item)
            cursor.execute('kill %s', _id)
    connection.close()

An easy way would be to restart the mysql server.. Open "services.msc" in windows Run, select Mysql from the list. Right click and stop the service. Then Start again and all the processes would have been killed except the one (the default reserved connection)

#! /bin/bash
if [ $# != "1" ];then
	echo "Not enough arguments.";
	echo "Usage: killQueryByDB.sh <db_name>";
	exit;
fi;

DB=${1};
for i in `mysql -u <user> -h localhost ${DB} -p<password> -e "show processlist" | sed 's/\(^[0-9]*\).*/\1/'`; do
	echo "Killing query ${i}";
	mysql -u <user> -h localhost ${DB} -p<password> -e "kill query ${i}";
done;

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

The following worked great for me:

echo "show processlist" | mysql | grep -v ^Id | awk '{print $1}' | xargs -i echo "KILL {}; | mysql"

I used the command flush tables to kill all inactive connections which where actually the mass problem.

Kill does not work if the running process is not yours. I merged some of these solutions and extended them to create a more simple one (at least to me).

m=mysql -p $password -h $host -u$user #you can also inline it of course 
for i in `$m -e "show processlist" | awk '/$anySearchString/ {print $1}'`; do $m -e "call mysql.rds_kill($i);"; done

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.

Query 1 select concat('KILL ',id,';') from information_schema.processlist where user='username' into outfile '/tmp/a.txt';

Query 2 source a.txt

This will enable you to kill all the queries in show processlist by specific user.