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DBMS_STORAGE_MAP

With DBMS_STORAGE_MAP, you can communicate with the Oracle background process FMON to invoke mapping operations that populate mapping views. FMON communicates with operating and storage system vendor-supplied mapping libraries.

This chapter discusses the following topics:

• Mapping Terminology
• Summary of DBMS_STORAGE_MAP Subprograms
• Usage Notes for DBMS_STORAGE_MAP Subprograms

Mapping Terminology

The following terminology and descriptions will help you understand the DBMS_STORAGE_MAP API:

• Mapping libraries

  Mapping libraries help you map the components of I/O processing stack elements. Examples of I/O processing components include files, logical volumes, and storage array I/O targets. The mapping libraries are identified in filemap.ora.

• Mapping files

  A mapping file is a mapping structure that describes a file. It provides a set of attributes, including file size, number of extents that the file is composed of, and file type.

• Mapping elements and subelements

  A mapping element is the abstract mapping structure that describes a storage component within the I/O stack. Examples of elements include mirrors, stripes, partitions, raid5, concatenated elements, and disks--structures that are the mapping building blocks. A mapping subelement describes the link between an element and the next elements in the I/O mapping stack

• Mapping file extents

  A mapping file extent describes a contiguous chunk of blocks residing on one element. This includes the device offset, the extent size, the file offset, the type (data or parity), and the name of the element where the extent resides. In the case of a raw device or volume, the file is composed of only one file extent component. A mapping file extent is different from Oracle extents.

  See Also: Oracle9i Database Administrator's Guide for more information Oracle9i Database Reference for V$MAP views, including V$MAP_FILE, V$MAP_ELEMENT, V$MAP_SUBELEMENT, V$MAP_FILE_EXTENT