Storage Engines

• InnoDB
  Basic configuration of InnoDB in /etc/my.cnf:
  # Uncomment the following if you are using InnoDB tables
innodb_data_home_dir = /usr/local/mysql/var
innodb_data_file_path = ibdata1:10M:autoextend
innodb_log_group_home_dir = /usr/local/mysql/var
# You can set .._buffer_pool_size up to 50 - 80 %
# of RAM but beware of setting memory usage too high
innodb_buffer_pool_size = 16M
innodb_additional_mem_pool_size = 2M
# Set .._log_file_size to 25 % of buffer pool size
innodb_log_file_size = 5M
innodb_log_buffer_size = 8M
innodb_flush_log_at_trx_commit = 1
innodb_lock_wait_timeout = 50

  Have it use separate files for InnoDB tables by adding to the [mysld] section (see Reclaim Your Hard Drive - Saving Tons of Space with MySQL InnoDB tables):

  innodb_file_per_table
• XtraDB

How do MyISAM and InnoDB Utilize HD Space?

At what point does MySQL INNODB fine tuning become a requirement?

http://vdachev.net/2007/02/22/mysql-reducing-ibdata1/
http://dev.mysql.com/doc/refman/5.5/en/innodb-data-log-reconfiguration.html