As with blobspaces and dbspaces, when you create a sbspace, you assign to it one or more chunks. However, the first chunk of an sbspace always has three areas:
Metadata identifies key aspects of the sbspace and each smart large object stored in the sbspace, and enables the database server to manipulate and recover smart large objects stored within.
User data is the smart large object data stored in the sbspace by user applications. The chunk has up to two user-data areas.
The database server allocates space from the reserved area to either the metadata or user-data area when more space is needed. The chunk has up to two reserved areas.
For information on correctly allocating metadata and user data for sbspaces, see Sizing Sbspace Metadata and the IBM Informix Dynamic Server Performance Guide.
When you add a chunk to an sbspace, you can specify whether it contains a metadata area and user-data area or whether to reserve the chunk exclusively for user data. You can add more chunks at any time. If you are updating smart large objects, I/O to the user data is much faster on raw disks than cooked chunk files. For instructions on how to create a sbspace, add chunks to a sbspace, or drop a chunk from a sbspace, see Managing Disk Space.