Structure of the metadata area
An sbspace contains a metadata area for each chunk in the sbspace.
As with the chunk header pages, four areas are exclusive
to the first chunk in a sbspace: the sbspace descriptor tblspace,
the chunk adjunct tblspace, and the level-1 and level-2 archive tblspaces.
The tblspace header section contains a tblspace header for each of
these tblspaces (notably excluding the tblspace tblspace). Figure 1 shows the layout of
the metadata in the single-chunk sbspace.
When you specify the sbspace name in the oncheck -ps option, you can display the number of pages allocated and used for each tblspace in the metadata area.
The following items describe
how the metadata area grows:
- The sbspace descriptor tblspace does not grow.
- The chunk adjunct tblspace grows as chunks are added.
- The LO header tblspace grows as large objects are added to the chunk.
- The tblspace for user-data free list grows if free spaces in the chunk are heavily fragmented.