Veritas Storage Foundation™ 5.0.1 for Oracle RAC Installation, Configuration, and Administrator's Guide Extracts for the HP Serviceguard Storage Management Suite on HP-UX 11i v3

Databases using file systems typically incur additional overhead:
• Extra CPU and memory usage to read data from underlying disks to the file system cache.
This scenario requires copying data from the file system cache to the Oracle cache.
• File locking that allows for only a single writer at a time. Allowing Oracle to perform locking
allows for finer granularity of locking at the row level.
• File systems generally go through a standard Sync I/O library when performing I/O. Oracle
can make use of Kernel Async I/O libraries (KAIO) with raw devices to improve performance.
ODM Communication
ODM uses port d to communicate with other ODM instances to support the file management
features of Oracle Managed Files (OMF). OMF enables DBAs to set init.ora parameters for db
datafile, controlfile, and logfile names and for those structures to be named automatically. OMF
allows for the automatic deletion of physical data files when DBAs remove tablespaces.
Additional Features of Serviceguard Extension for RAC
Additional SGeRAC features include:
• The ability to transition from a local high-availability cluster into a disaster recovery
environment. This environment ensures maximum data protection and availability in the
event of large-scale disasters and involves the global clustering feature of SGeRAC and
replication with Veritas Volume Replicator (VVR).
• The ability to back up and recover data at the volume and file system levels using Veritas
Storage Checkpoints and Veritas Database FlashSnap.
• The ability to evaluate or troubleshoot I/O performance with Veritas Storage Mapping. You
can access mapping information that allows for a detailed understanding of the storage
hierarchy in which files reside.
Additional Features of Serviceguard Extension for RAC 19