Structure of the Root Dbspace

As part of disk-space initialization, the database server initializes specific structures in the initial chunk of the root dbspace.

The following structures are initialized:
  • Twelve reserved pages
  • The first chunk free-list page
  • The tblspace tblspace
  • The physical log
  • The logical-log files
  • The database tblspace

The ROOTNAME, ROOTOFFSET, ROOTPATH, and ROOTSIZE configuration parameters specify the size and location of the initial chunk of the root dbspace. If the root dbspace is mirrored, the MIRROROFFSET and MIRRORPATH configuration parameters specify the mirror-chunk location. For more information about these parameters, see Database configuration parameters.

To see the structure of the root chunk use the oncheck -pe command. For more information, see oncheck -ce, -pe: Check the chunk-free list.