Veritas Storage Foundation for Oracle 5.0 Administrator's Guide, HP-UX 11i v3, Second Edition, December 2008

Oracle file mapping (ORAMAP)
Veritas has defined and implemented two libraries: libvxoramap_64.so for HPUX
PA and libvxoramap_64.sl for HPUX IA architecture.
These two libraries provide a mapping interface to Oracle9 release 2 or later. The
libvxoramap_64.so library serves as a bridge between Oracle's set of storage APIs
(known as “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.
With Veritas Storage Foundation for Oracle Storage Mapping option, you can
view the complete I/O topology mapping of datafiles through intermediate layers
like logical volumes down to actual physical devices. This information can be used
to determine the exact location of an Oracle data block on a physical device and
to help identify hot spots.
Note: To use the mapping functionality, you must be using Oracle 9.2.0.3 or later.
Mapping components
You need to understand the mapping components in the System Global Area (SGA)
and Oracle's representation of these components before you can interpret the
mapping information in Oracle's dynamic performance views.
The mapping information in Oracle's dynamic performance views consists of:
■ File components
A mapping file component is a mapping structure describing a file. It provides
a set of attributes for a file, including the file's size, number of extents, and
type. File components are exported to the user through V$MAP_FILE.
■ File extent components
A mapping file extent component describes a contiguous group of blocks
residing on one element. The description specifies the device offset, the extent
size, the file offset, the extent type (Data or Parity), and the 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.
Using Storage Mapping
Oracle file mapping (ORAMAP)
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