【MySQL 5.7 Reference Manual】15.4.5 System Tablespace（系统表空间）

15.4.5 System Tablespace（系统表空间）

The InnoDB system tablespace contains the InnoDB data dictionary (metadata for InnoDB-related objects) and is the storage area for the doublewrite buffer, the change buffer, and undo logs. The system tablespace also contains table and index data for any user-created tables that are created in the system tablespace. The system tablespace is considered a shared tablespace since it is shared by multiple tables.

InnoDB系统表空间包含了InnoDB数据字典（InnoDB相关对象的元数据）并且还是双写缓冲、变更缓冲和undo日志的存储区域。系统表空间也包含了系统表空间中任意用户表的表数据和索引数据。如果系统表空间被多个表所共享，那么它会被当作一个共享表空间。

The system tablespace is represented by one or more data files. By default, one system data file, named ibdata1, is created in the MySQL data directory. The size and number of system data files is controlled by the innodb_data_file_pathstartup option.

系统表空间表现为一个或多个数据文件。默认情况下，一个名为iddata1的系统数据文件被创建在MySQL数据目录中。数据文件的大小通过innodb_data_file_pathstartup选项来控制。

For related information, see Section 15.6.1, “InnoDB Startup Configuration”, and Section 15.7.1, “Resizing the InnoDB System Tablespace”.

更多相关信息，请参考15.6.1，“InnoDB启动配置”，和15.7.1，“重新调整InnoDB系统表空间的大小”。