Monitoring the metadata and user-data areas

The database server reserves 40 percent of the user-data area as a reserved area. The database server uses this reserved space for either the metadata or user data. The metadata area gets used up as smart large objects are added to that sbspace. When the database server runs out of metadata or user-data space, it moves a block of the reserved space to the corresponding area.

When all of the reserve area is used up, the database server cannot move space to the metadata area, even if the user-data area contains free space.

  1. As you add smart large objects to the sbspace, use oncheck -pe or onstat -g smb c to monitor the space in the metadata area, user-data area, and reserved area. For an example, see The oncheck -ce and oncheck -pe options.
  2. Use the message log to monitor metadata stealing.

    The database server prints messages about the number of pages allocated from the reserved area to the metadata area.

  3. Add another chunk to the sbspace before the sbspace runs out of space in the metadata and reserved areas.

    For more information, see Adding a chunk to an sbspace.

  4. The database server writes the FREE_RE and CHKADJUP log records when it moves space from the reserve area to the metadata or user-data area.

For more information, see Size sbspace metadata.


Copyright© 2019 HCL Technologies Limited