30.4.3.7 The innodb_buffer_stats_by_schema and x$innodb_buffer_stats_by_schema Views

These views summarize the information in the INFORMATION_SCHEMA INNODB_BUFFER_PAGE table, grouped by schema. By default, rows are sorted by descending buffer size.

Warning

Querying views that access the INNODB_BUFFER_PAGE table can affect performance. Do not query these views on a production system unless you are aware of the performance impact and have determined it to be acceptable. To avoid impacting performance on a production system, reproduce the issue you want to investigate and query buffer pool statistics on a test instance.

The innodb_buffer_stats_by_schema and x$innodb_buffer_stats_by_schema views have these columns:

• object_schema

  The schema name for the object, or InnoDB System if the table belongs to the InnoDB storage engine.

• allocated

  The total number of bytes allocated for the schema.

• data

  The total number of data bytes allocated for the schema.

• pages

  The total number of pages allocated for the schema.

• pages_hashed

  The total number of hashed pages allocated for the schema.

• pages_old

  The total number of old pages allocated for the schema.

• rows_cached

  The total number of cached rows for the schema.