Oracle Database 10g: “g” Stands for Grid

Oracle has created the grid computing infrastructure software that balances all types of
workloads across servers and enables all those servers to be managed as one complete system.

Oracle 10g allows companies to begin evolving their IT toward a grid computing model. For storage, databases, application servers, and applications, Oracle’s new technology meets the requirements of grid computing.

A grid can be built with open system technologies, such as Intel processors and the Linux operating system, at a very low cost.

Enterprise grid computing lowers costs by:
• Increasing hardware utilization and resource sharing
• Enabling companies to scale out incrementally with low-cost components
• Reducing management and administration requirements

Oracle’s grid computing technology includes:
(1) Storage Grid
(2) Database Grid
(3) Application Grid
(4) Grid Control

STORAGE GRID : Automatic Storage Management (ASM)

Automatic Storage Management simplifies storage management for Oracle Databases. By abstracting the details of storage management, Oracle improves data access performance through sophisticated data provisioning, without requiring additional work from DBAs. Instead of managing many database files, Oracle DBAs manage only a small number of disk groups. A disk group is a set of disk devices that Oracle manages as a single, logical unit. An administrator can define a particular disk group as the default disk group for a database and Oracle automatically allocates storage for and creates or deletes the files associated with the database object. Automatic Storage Management also offers the benefits of storage technologies such as RAID or Logical Volume Managers (LVMs). Oracle can balance I/O from multiple databases across all of the devices in a disk group and it implements striping and mirroring to improve I/O performance and data reliability. In addition, Oracle can reassign disks from node to node and cluster to cluster, automatically reconfiguring the group. Because Automatic Storage Management is written to work exclusively with Oracle, it achieves better performance than generalized storage virtualization solutions.

DATABASE GRID : Real Application Clusters (RAC)

Oracle Real Application Clusters enables a single database to run across multiple clustered nodes in a grid, pooling the processing resources of several standard machines. Oracle is uniquely flexible in its ability to provision workload across machines because it is the only database technology that does not require data to be partitioned and distributed along with the work. In Oracle 10g, the database can immediately begin balancing workload across a new node with new processing capacity as it gets re-provisioned from one database to another, and can relinquish a machine when it is no longer needed— this is capacity on demand. Other databases cannot grow and shrink while running and, therefore, cannot utilize hardware as efficiently. New integrated clusterware in Oracle 10g makes clustering easy by eliminating the need to purchase, install, configure, and support third-party clusterware. Servers can be easily added and dropped to an Oracle cluster with no downtime. Oracle has the only database technology to include clusterware for all operating systems, which dramatically reduces the opportunities for failure in a clustered environment

APPLICATION GRID : Oracle Streams

Oracle Streams provides a set of elements that allow users to control what information is put into a stream, how the stream flows or is routed from node to node, what happens to events in the stream as they flow into each node, and how the stream terminates. By specifying the configuration of the elements acting on the stream, a user can address specific requirements.

GRID CONTROL : Enterprise Manager Grid Control

Oracle Enterprise Manager 10g Grid Control is the complete, integrated, central management console and underlying framework that automates administrative tasks across sets of systems in a grid environment. Grid Control helps reduce administration costs through automation and policy-based standardization. With Oracle Grid Control, IT professionals can group multiple hardware nodes, databases, application servers, and other targets into single logical entities. By executing jobs, enforcing standard policies, monitoring performance and automating many other tasks across a group of targets instead of on many systems individually, Grid Control enables IT staff to scale with a growing grid. Because of this feature, the existence of many small computers in a grid infrastructure does not increase management complexity.
Enterprise grid computing builds a critical software infrastructure that can run on large numbers of small, networked computers, by combining two related concepts:

Implement One from Many :
Grid computing coordinates the use of clusters of machines to create a single logical entity, such as a database or an application server. By distributing work across many servers, grid computing exhibits benefits of availability, scalability, and performance using low-cost components. Because a single logical entity is implemented across many machines, companies can add or remove capacity in small increments, online. With the capability to add capacity on demand to a particular function, companies get more flexibility for adapting to peak loads, thus achieving better hardware utilization and better business responsiveness.

Manage Many as One :
Grid computing allows you to manage and administer groups of machines, groups of database instances, and groups of application servers at low-cost. Grid computing first removes many of the administrative costs of managing a single system by making each database and each application server adaptive to changing circumstances. Then, the model makes managing many systems simple, by allowing them to be managed as a single logical entity.

Note :This above information has been collected from one of the oracle pubhished white paper.