Spec-Zone .ru
спецификации, руководства, описания, API
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Spec-Zone .ru
спецификации, руководства, описания, API
|
This section describes what you can do when your InnoDB system
tablespace runs out of room or when you want to change the size of the redo log
files.
The easiest way to increase the size of the InnoDB system tablespace is to
configure it from the beginning to be auto-extending. Specify the autoextend
attribute for the last data file in the tablespace definition. Then InnoDB
increases the size of that file automatically in 8MB increments when it runs out of space. The increment size
can be changed by setting the value of the innodb_autoextend_increment system variable, which is measured in megabytes.
You can expand the system tablespace by a defined amount by adding another data file:
Shut down the MySQL server.
If the previous last data file is defined with the keyword autoextend,
change its definition to use a fixed size, based on how large it has actually grown. Check the size of
the data file, round it down to the closest multiple of 1024 × 1024 bytes (= 1MB), and specify this
rounded size explicitly in innodb_data_file_path.
Add a new data file to the end of innodb_data_file_path, optionally making that file auto-extending. Only
the last data file in the innodb_data_file_path can be specified as auto-extending.
Start the MySQL server again.
For example, this tablespace has just one auto-extending data file ibdata1:
innodb_data_home_dir =innodb_data_file_path = /ibdata/ibdata1:10M:autoextend
Suppose that this data file, over time, has grown to 988MB. Here is the configuration line after modifying the original data file to use a fixed size and adding a new auto-extending data file:
innodb_data_home_dir =innodb_data_file_path = /ibdata/ibdata1:988M;/disk2/ibdata2:50M:autoextend
When you add a new data file to the system tablespace configuration, make sure that the filename does not refer
to an existing file. InnoDB creates and initializes the file when you restart the
server.
Currently, you cannot remove a data file from the system tablespace. To decrease the system tablespace size, use this procedure:
Use mysqldump to dump all your InnoDB tables, including InnoDB tables located
in the MySQL database. As of 5.6, there are five InnoDB tables included in
the MySQL database:
mysql> select table_name from information_schema.tables where table_schema='mysql' and engine='InnoDB';+----------------------+| table_name |+----------------------+| innodb_index_stats || innodb_table_stats || slave_master_info || slave_relay_log_info || slave_worker_info |+----------------------+5 rows in set (0.00 sec)
Stop the server.
Remove all the existing tablespace files (*.ibd),
including the ibdata and ib_log files. Do
not forget to remove *.ibd files for tables located in the MySQL database.
Remove any .frm files for InnoDB
tables.
Configure a new tablespace.
Restart the server.
Import the dump files.
If your databases only use the InnoDB engine, it may be simpler to
dump all databases, stop the server, remove all databases and
InnoDB log files, restart the server, and import the dump files.
To change the number or the size of InnoDB log files in MySQL 5.6.7 or earlier, use
the following instructions. The procedure to use depends on the value of innodb_fast_shutdown, which determines whether or not to bring the system
tablespace fully up-to-date before a shutdown operation:
If innodb_fast_shutdown is not set to 2: Stop the MySQL server and make sure
that it shuts down without errors, to ensure that there is no information for outstanding transactions
in the redo log. Copy the old redo log files to a safe place, in case something went wrong during the
shutdown and you need them to recover the tablespace. Delete the old log files from the log file
directory, edit my.cnf to change the log file configuration, and start the
MySQL server again. mysqld sees that no InnoDB log files exist at startup and creates new ones.
If innodb_fast_shutdown is set to 2: Set innodb_fast_shutdown to 1:
mysql> SET GLOBAL innodb_fast_shutdown =
1;
Then follow the instructions in the previous item.
As of MySQL 5.6.8, the innodb_fast_shutdown setting is no longer relevant when changing the number or
the size of InnoDB log files. Additionally, you are no longer required remove old
log files, although you may still want to copy the old log files to a safe place, as a backup. To change the
number or size of InnoDB log files, perform the following steps:
Stop the MySQL server and make sure that it shuts down without errors.
Edit my.cnf to change the log file configuration. To
change the log file size, configure innodb_log_file_size. To increase the number of log files, configure
innodb_log_files_in_group.
Start the MySQL server again.
If InnoDB detects that the innodb_log_file_size differs from the redo log file size, it will write a log
checkpoint, close and remove the old log files, create new log files at the requested size, and open the new log
files.