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In 10g database release, Oracle
provides many technology differentiators and also grid technology
enablers. Some of these are new additions and some are enhancements.
To name a few, data pump utilities is an addition in 10g release and
cross-platform transportable tablespace is an enhancement. Automatic
Storage management is another notable addition in 10g release.
The Database Processing is a key
component in any Grid Framework. At the same time, data movement,
data loading and data sharing among the databases and non-database
computing areas, is a key prerequisite for the Data Grid
implementation. The Oracle Storage Management is an important
component in dealing with resource provision. ASM makes the
adjustment of disk resources quite transparent.
Many of the well-known and minor
features of the Oracle database product are enhanced with a view to
participate actively in the Grid Architecture. For Example, the
easier data transfers using data pump, Oracle data files transfers
among different operating systems, quicker and easier software
installation, new replication and messaging methods using the
Streams technology etc., are the new features Oracle has emphasized.
Grid Control is well designed to
manage besides the databases, the web applications, the application
servers and hosts of different operating systems. Grid control
provides a bird?s eye view of all resources for easier management.
Oracle 10g database has many new
and innovative features to facilitate the setting up of multiple
databases in a clustered environment and non-clustered grid
environment. It has the advantage of leveraging the underlying grid
infrastructure components and manages them efficiently. The grid
components such as low cost servers or blades, powerful interconnect
and storage arrays are well utilized by the Oracle 10g database.
Grid Enabling Components
Oracle 10g Database comes
equipped with many grid-enabling technologies. The following
sections will introduce some of these technologies.
Automatic Storage Management
ASM simplifies and manages the
storage requirements needed to support the database. It provides
data provisioning methods. As the demand for data arises, new disk
devices can be added dynamically. Within a specific disk group,
Oracle automatically allocates the storage, creates and deletes the
data files as needed for the database. The detection of hot spots
and I/O balancing functions are managed by the ASM methodology,
thereby lessening the manual intervention by DBA and SA. ASM also
offers the benefit of the RAID and logical volume functionality
Oracle is capable of reassigning
disks from one node to another and from one cluster to another.
Oracle can also balance the IO activity from multiple databases
across all of the devices in disk group. It can also implement
striping and mirroring methodology to improve the IO performance.
Storage can be assigned when needed and can be removed when it is
not needed. This gives a true grid friendly functionality.
As previously noted in this
text, the Cluster software is the software stack that defines,
configures and manages the cluster members or the cluster nodes.
Cluster software, sometimes called the cluster manager, keeps track
of the health of the nodes and communicates with the cluster
database system. In order to provide a uniform cluster software
stack across many operating systems and platforms, Oracle has
introduced Portable Clusterware to support the Oracle Real
By supplying uniform, standard
and integrated cluster software, cluster vendor imposed limitations
such as number of nodes and using a particular type of interconnect
technology etc., are avoided. Now Oracle RAC implementations will
have a common look and feel even if they are implemented on
different operating systems and different server hardware. In the
Grid Environment, where the RAC database systems become a key
component, Portable Clusterware adds to the functionality and eases