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Oracle Grid & Real Application Clusters. To get immediate
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Oracle Database - A Consumer
of Grid Resources
The Oracle Database is a consumer of grid resources, such as the
computing resources (aka. servers), storage units and provider of
the data resources for the application users. It is capable of
managing and provisioning the cluster and storage resources to
different databases running in the grid environment.
Oracle 10g database has many new
and innovative features facilitating for 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 very well utilized by the Oracle
Grid Enabling Components
Oracle 10g Database comes
equipped with many grid-enabling technologies and they are examined
in the following sections.
Automatic Storage Management
ASM simplifies 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. 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 I/O activity from multiple databases
across all of the devices in disk group. It can also implement
striping and mirroring methodology to improve the I/O performance.
The capacity to manage the
storage supporting the database enables optimum utilization of the
storage resources. Storage can be assigned when needed and can be
removed when it is not needed. This gives a true Grid-Friendly
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 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
Application Cluster. This avoids purchase, install, and
configuration of third-party cluster vendor.
By supplying uniform, standard,
and integrated cluster software, cluster vendor imposed limitations
such as the number of nodes and using a particular type of
interconnect technology, 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.
Support for Infiniband
Any large scale implementation
of Oracle RAC involving a large set of nodes has to depend on a
reliable, low latency and high bandwidth interconnect. The
architecture also requires having redundant switches to support
large interconnect connections.
With the support for Infiniband
interconnect and I/O connectivity technology, Oracle 10g is able to
get better performance and scalability. With the support and
availability of Infiniband for Oracle database and Oracle RAC
Clusters, client to server, server to server, and server to storage
communication achieve higher throughput and reduced bottlenecks.
Oracle Real Application
Oracle Real Application Cluster
utilizes the commodity style servers or blades to provide a scalable
and high performing database computing resource. Highly available
and scalable Oracle RAC database becomes the main building blocks
for large Data Grids for consolidating and processing large volume
of the corporate data. With its shared storage model, and with
multiple instances, RAC database can scale well and meet the
challenge of uneven database processing loads. Oracle RAC is well
suited for the provisioning of blades or servers as the need arises.
Oracle RAC also offers automatic
workload management for services within a RAC a database. RAC can
automatically load-balance connections as they are made across
instances hosting a service. It is relatively easy to add and
subtract instances or blade servers into the cluster.
The bulk of the material in this
book is focused on Oracle RAC.