VERITAS Storage Foundation 4.1 for Oracle RAC HP Serviceguard Storage Management Suite Extracts, December 2005
Oracle File Mapping (ORAMAP)
Oracle File Mapping (ORAMAP)
VERITAS has defined and implemented two libraries: libvxoramap_64.so (HPUX PA)
and libvxoramap_64.sl (HPUX IA). These two libraries provide a mapping interface
to Oracle9i release 2 or a later release. libvxoramap_64.so serves as a bridge between
the Oracle set of storage APIs (ORAMAP) and VERITAS Federated Mapping Service
(VxMS), a library that assists in the development of distributed SAN applications that
must share information about the physical location of files and volumes on a disk.
The VERITAS Storage Mapping option enables you to view the complete I/O topology
mapping of datafiles from logical volumes to actual physical devices. Use this information
to determine the exact location of an Oracle data block on a physical device and to help
identify hot spots.
Note Mapping requires Oracle 9.2.0.3 or a later version.
Mapping Components
This section covers the mapping components in the System Global Area (SGA) and the
representation of these components by Oracle. You must understand these components to
interpret the mapping information in Oracle dynamic performance views.
The mapping information in the dynamic performance views consists of:
◆ File components
A mapping file component is a mapping structure describing a file. This component
provides a set of attributes for a file, including the size, number of extents, and type.
v$map_file exports file components to the user.
◆ File extent components
A mapping file extent component describes a contiguous group of blocks residing on
one element. The description specifies the device offset, extent size, file offset, extent
type (Data or Parity), and name of the element where the extent resides.
◆ Element components
A mapping element component is a mapping structure that describes a storage
component within the I/O stack. Elements can be mirrors, stripes, partitions, RAID5,
concatenated elements, and disks.
This component contains information about the mapping structure, such as the size,
type, number of subelements, and a brief description of the element.
v$map_element exports element components are exported to the user.
Chapter 8, Using Storage Mapping 157