This section describes what you can do when your
InnoDB tablespace runs out of room or when you
want to change the size of the log files.
From MySQL 3.23.50 and 4.0.2, the easiest way to increase the size
InnoDB 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
increases the size of that file automatically in 8MB increments
when it runs out of space. Starting with MySQL 4.0.24 and 4.1.5,
the increment size can be changed by setting the value of the
system variable, which is measured in MB.
Alternatively, you can increase the size of your tablespace by
adding another data file. To do this, you have to shut down the
MySQL server, change the tablespace configuration to add a new
data file to the end of
innodb_data_file_path, and start
the server again.
If your last data file was defined with the keyword
autoextend, the procedure for reconfiguring the
tablespace must take into account the size to which the last data
file has grown. Obtain the size of the data file, round it down to
the closest multiple of 1024 × 1024 bytes (= 1MB), and
specify the rounded size explicitly in
innodb_data_file_path. Then you
can add another data file. Remember that only the last data file
be specified as auto-extending.
As an example, assume that the tablespace has just one
auto-extending data file
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 not be auto-extending and adding another auto-extending data file:
innodb_data_home_dir = innodb_data_file_path = /ibdata/ibdata1:988M;/disk2/ibdata2:50M:autoextend
When you add a new file to the tablespace configuration, make sure
that it does not exist.
InnoDB will create and
initialize the file when you restart the server.
Currently, you cannot remove a data file from the tablespace. To decrease the size of your tablespace, use this procedure:
Use mysqldump to dump all your
Stop the server.
Remove all the existing tablespace files, including the
files. If you want to keep a backup copy of the information,
then copy all the
ib* files to another
location before the removing the files in your MySQL
.frm files for
Configure a new tablespace.
Restart the server.
Import the dump files.
If you want to change the number or the size of your
InnoDB log files, 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 log). Copy
the old log files into 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
InnoDB log files exist at
startup and creates new ones.