How can I change the default Mysql connection timeout when connecting through python?
Question:
I connected to a mysql database using python con = _mysql.connect('localhost', 'dell-pc', '', 'test')
The program that I wrote takes a lot of time in full execution i.e. around 10 hours. Actually, I am trying to read distinct words from a corpus.
After reading was finished there was a timeout error.
I checked Mysql default timeouts which were:
+----------------------------+----------+
| Variable_name | Value |
+----------------------------+----------+
| connect_timeout | 10 |
| delayed_insert_timeout | 300 |
| innodb_lock_wait_timeout | 50 |
| innodb_rollback_on_timeout | OFF |
| interactive_timeout | 28800 |
| lock_wait_timeout | 31536000 |
| net_read_timeout | 30 |
| net_write_timeout | 60 |
| slave_net_timeout | 3600 |
| wait_timeout | 28800 |
+----------------------------+----------+
How can I change the default timeout ?
Answers:
You change default value in MySQL configuration file (option connect_timeout in mysqld section) –
[mysqld]
connect_timeout=100
If this file is not accessible for you, then you can set this value using this statement –
SET GLOBAL connect_timeout=100;
Do:
con.query('SET GLOBAL connect_timeout=28800')
con.query('SET GLOBAL interactive_timeout=28800')
con.query('SET GLOBAL wait_timeout=28800')
Parameter meaning (taken from MySQL Workbench in Navigator: Instance > Options File > Tab "Networking" > Section "Timeout Settings")
- connect_timeout: Number of seconds the mysqld server waits for a connect packet before responding with ‘Bad handshake’
- interactive_timeout Number of seconds the server waits for activity on an interactive connection before closing it
- wait_timeout Number of seconds the server waits for activity on a connection before closing it
BTW: 28800 seconds are 8 hours, so for a 10 hour execution time these values should be actually higher.
I know this is an old question but just for the record this can also be done by passing appropriate connection options as arguments to the _mysql.connect call. For example,
con = _mysql.connect(host='localhost', user='dell-pc', passwd='', db='test',
connect_timeout=1000)
Notice the use of keyword parameters (host, passwd, etc.). They improve the readability of your code.
For detail about different arguments that you can pass to _mysql.connect, see MySQLdb API documentation
MAX_EXECUTION_TIME is also an important parameter for long running queries.Will work for MySQL 5.7 or later.
Check the current value
SELECT @@GLOBAL.MAX_EXECUTION_TIME, @@SESSION.MAX_EXECUTION_TIME;
Then set it according to your needs.
SET SESSION MAX_EXECUTION_TIME=2000;
SET GLOBAL MAX_EXECUTION_TIME=2000;
I connected to a mysql database using python con = _mysql.connect('localhost', 'dell-pc', '', 'test')
The program that I wrote takes a lot of time in full execution i.e. around 10 hours. Actually, I am trying to read distinct words from a corpus.
After reading was finished there was a timeout error.
I checked Mysql default timeouts which were:
+----------------------------+----------+
| Variable_name | Value |
+----------------------------+----------+
| connect_timeout | 10 |
| delayed_insert_timeout | 300 |
| innodb_lock_wait_timeout | 50 |
| innodb_rollback_on_timeout | OFF |
| interactive_timeout | 28800 |
| lock_wait_timeout | 31536000 |
| net_read_timeout | 30 |
| net_write_timeout | 60 |
| slave_net_timeout | 3600 |
| wait_timeout | 28800 |
+----------------------------+----------+
How can I change the default timeout ?
You change default value in MySQL configuration file (option connect_timeout in mysqld section) –
[mysqld]
connect_timeout=100
If this file is not accessible for you, then you can set this value using this statement –
SET GLOBAL connect_timeout=100;
Do:
con.query('SET GLOBAL connect_timeout=28800')
con.query('SET GLOBAL interactive_timeout=28800')
con.query('SET GLOBAL wait_timeout=28800')
Parameter meaning (taken from MySQL Workbench in Navigator: Instance > Options File > Tab "Networking" > Section "Timeout Settings")
- connect_timeout: Number of seconds the mysqld server waits for a connect packet before responding with ‘Bad handshake’
- interactive_timeout Number of seconds the server waits for activity on an interactive connection before closing it
- wait_timeout Number of seconds the server waits for activity on a connection before closing it
BTW: 28800 seconds are 8 hours, so for a 10 hour execution time these values should be actually higher.
I know this is an old question but just for the record this can also be done by passing appropriate connection options as arguments to the _mysql.connect call. For example,
con = _mysql.connect(host='localhost', user='dell-pc', passwd='', db='test',
connect_timeout=1000)
Notice the use of keyword parameters (host, passwd, etc.). They improve the readability of your code.
For detail about different arguments that you can pass to _mysql.connect, see MySQLdb API documentation
MAX_EXECUTION_TIME is also an important parameter for long running queries.Will work for MySQL 5.7 or later.
Check the current value
SELECT @@GLOBAL.MAX_EXECUTION_TIME, @@SESSION.MAX_EXECUTION_TIME;
Then set it according to your needs.
SET SESSION MAX_EXECUTION_TIME=2000;
SET GLOBAL MAX_EXECUTION_TIME=2000;