MySQL 5.5 Release Notes
This section describes how to increase or decrease the size of the
InnoDB system tablespace.
Increasing the Size of the InnoDB System Tablespace
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 ininnodb_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 theinnodb_data_file_pathcan 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.
Decreasing the Size of the InnoDB System Tablespace
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
InnoDBtables.Stop the server.
Remove all the existing tablespace files, including the
ibdataandib_logfiles. If you want to keep a backup copy of the information, then copy all theib*files to another location before the removing the files in your MySQL installation.Remove any
.frmfiles forInnoDBtables.Configure a new tablespace.
Restart the server.
Import the dump files.