MySQL Query Timeout

  • Document ID:7022168
  • Creation Date:24-Oct-2017
  • Modified Date:23-Jan-2020
    • Micro Focus Products:
      Retain Unified Archiving

Environment

Retain 4.x
MySQL 5.5+
MariaDB

Situation

When running a query in MySQL and it takes a long time to process from the command line, the following error is seen:
  • ERROR 1205 (HY000): Lock wait timeout exceeded; try restarting transaction

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Resolution

The timeout can be increased by running the following from within mysql

SET innodb_lock_wait_timeout=100;

Some versions of MySQL and MariaDB do not support this method so an alternative is required:
  • Ensure /etc/my.cnf contains the !include line
# cat /etc/my.cnf | grep -v '#'
[client]

[mysqld]

bind-address    = 127.0.0.1

log-error       = /var/log/mysql/mysqld.log

secure_file_priv = /var/lib/mysql-files

innodb_file_format=Barracuda
innodb_file_per_table=ON

server-id       = 1

sql_mode=NO_ENGINE_SUBSTITUTION,STRICT_TRANS_TABLES

[mysqld_multi]
mysqld     = /usr/bin/mysqld_safe
mysqladmin = /usr/bin/mysqladmin
log        = /var/log/mysqld_multi.log

!includedir /etc/my.cnf.d
  • Create a new file called /etc/my.cnf.d/custom.cnf with the following contents
[mysqld]
innodb_lock_wait_timeout=100
  • Restart the database
# systemctl restart mariadb.service 

Where the timeout is in seconds.  A higher value may be required in some circumstances.

Additional Information

To enter the database administration tool and check the settings

# mysql --user=root --password=<password entered during installation>
Welcome to the MariaDB monitor.  Commands end with ; or \g.
Your MariaDB connection id is 8
Server version: 10.2.29-MariaDB SUSE package

Copyright (c) 2000, 2018, Oracle, MariaDB Corporation Ab and others.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

MariaDB [(none)]> show global variables like '%innodb_lock%';
+--------------------------------+-------+
| Variable_name                  | Value |
+--------------------------------+-------+
| innodb_lock_schedule_algorithm | fcfs  |
| innodb_lock_wait_timeout       | 50    |
| innodb_locking_fake_changes    | OFF   |
| innodb_locks_unsafe_for_binlog | OFF   |
+--------------------------------+-------+
4 rows in set (0.00 sec)

MariaDB [(none)]> exit;
Bye