I have a script running a batch of very similar queries.
All of them, except one, run without any problem.
Only one query is getting stuck.
In "show processlist" the query has state=null
According to docs, show processlist should report "State=null" only for the "show processlist" thread itself.
Server version: 5.0.67 MySQL Community Server (GPL)
mysql> show processlist;
+---------+--------+-----------+--------------+---------+------+-------+------------------------------------------------------------------------------------------------------+
| Id | User | Host | db | Command | Time | State | Info |
+---------+--------+-----------+--------------+---------+------+-------+------------------------------------------------------------------------------------------------------+
| 3866613 | user | localhost | db_name | Query | 1986 | NULL | select log_time,log_action,log_action_id,log_object_id, #abcde:=if(log_action='abcde',to_ |
| 3873414 | root | localhost | NULL | Query | 0 | NULL | show processlist |
+---------+--------+-----------+--------------+---------+------+-------+------------------------------------------------------------------------------------------------------+
2 rows in set (0.00 sec)
Could be a bug of your version of mysql, take a look at this bug for more information .
Related
I have a 2.6GB file which I need to import and I used the command
sudo mysql -u root -p <dbname> > ~/<filename>.sql
I created a database from phpmyadmin and ran the above command.
It has been running for 30 minutes and when I run SHOW PROCESSLIST; on a separate window I get this
mysql> SHOW PROCESSLIST;
+-----+------+-----------+------+---------+------+-------+------------------+
| Id | User | Host | db | Command | Time | State | Info |
+-----+------+-----------+------+---------+------+-------+------------------+
| 149 | root | localhost | test | Sleep | 1716 | | NULL |
| 155 | root | localhost | NULL | Query | 0 | init | SHOW PROCESSLIST |
+-----+------+-----------+------+---------+------+-------+------------------+
2 rows in set (0.00 sec)
What is happening and why is it gone to sleep? How do I solve this?
It turns out that mysql server in preferences keeps shutting down whenever I start it. How do I solve this?
A mysql query is running from last 24 hours and when we are trying to kill that query, it is saying you are not the owner of the query so you can't kill this query.
Do we know how to kill any running query?
run below query for show all running query
SHOW PROCESSLIST;
it will show all query in execution.
e.g
+-----+------+-----------+------+---------+------+----------+------------------+
| Id | User | Host | db | Command | Time | State | Info |
+-----+------+-----------+------+---------+------+----------+------------------+
| 253 | root | localhost | NULL | Query | 0 | starting | show PROCESSLIST |
+-----+------+-----------+------+---------+------+----------+------------------+
after that run below query
kill 253;
will kill that query
Is it possible to find the process ID or the command that is executed for a rollback ?
More specifically :
The Information_Schema of MySQL has a specific table named processlist. This contains the details about every ongoing process in MySQL. An example of the table looks like this:
mysql> select * from processlist;
+----+------+-----------+--------------------+---------+------+------------+---------------------------+
| ID | USER | HOST | DB | COMMAND | TIME | STATE | INFO |
+----+------+-----------+--------------------+---------+------+------------+---------------------------+
| 5 | root | localhost | information_schema | Query | 5 | User sleep | select sleep(20) |
| 4 | root | localhost | information_schema | Query | 0 | executing | select * from processlist |
+----+------+-----------+--------------------+---------+------+------------+---------------------------+
Is it possible for me to intercept a Rollback and grab its ID or INFO from this table ? The issue I have been facing is that any Rollback I execute gets completed before I am able to intercept its ID from the Table.
how to send mail alert for MySQL?
can we send alerts when the MySQL has large number of connections, or MySQL is not responding properly. Can someone help me to solve this prolem ?
You can do this in a number of ways. SHOW FULL PROCESSLIST; query would give you information about the number of connections as well as the queries being executed by each connection(thread). A sample result is as follows.
mysql> SHOW FULL PROCESSLIST;
+------+------+--------------------+------+---------+------+-------+-----------------------+
| Id | User | Host | db | Command | Time | State | Info |
+------+------+--------------------+------+---------+------+-------+-----------------------+
| 1298 | root | 192.168.1.76:37648 | NULL | Sleep | 0 | | NULL |
| 1491 | root | localhost | NULL | Query | 0 | init | show full processlist |
+------+------+--------------------+------+---------+------+-------+-----------------------+
If you are only concerned with the number of current connection(threads) you can use the following query.
mysql> SHOW STATUS WHERE `variable_name` = 'Threads_connected';
+-------------------+-------+
| Variable_name | Value |
+-------------------+-------+
| Threads_connected | 2 |
+-------------------+-------+
Now about the mail alerts, you can setup a cron job(shell script) to fire a mail alert as soon as the number of current connections exceed a certain limit. mail command can be used for this.
$ echo "Max MySQL Connections reached"| mail -s "your subject" your#email.com
Also, I came across a great MySQL Monitoring tool- MONyog. It would let you setup mail alerts for any of the MySQL variable.
Can anyone tell me how can I kill all the sleeping processes?
I searched for it and I found that we can do it by command
mk-kill --match-command Sleep --kill --victims all --interval 10
I connected the DB server(Linux) but I find the message that command not found.
I tried to connect via MYSQL administrator and it doesn't say that command not found but also doesn't executes the query , just says you have an SQl error
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 55;
Query OK, 0 rows affected (0.00 sec)
kill $queryID; is helpful but if there is only one query causing an issue;
Having a lot of MySQL sleeping processes can cause a huge spike in your CPU load or IO
Here is a simple one-line command (if behind the MySQL server is linux) which would kill all of the current sleeping MySQL processes:
for i in `mysql -e "show processlist" | awk '/Sleep/ {print $1}'` ; do mysql -e "KILL $i;"; done
This is only a temporary repair; I strongly advise identifying and addressing the problem's main cause.
For instance, you may set the wait timeout variable to the amount of time you want MySQL to hold open connections before shutting them.
But if the issue still persists and you have to investigate the DB queries that cause the problem there is another way. In screen session, you can use another while cycle to continuously kill the sleeping queries. (while there is an output of the mysql show processlit | grep -i sleep | awk id column and kill it.) If you are using MySQL replication between different hosts this will help them to catch up. So when using show slave status\G; Seconds_behind_master will be going to catch up.
Of course, you should investigate the root cause again.