Oracle's Parallel Server is unique among clustering solutions in that it breaks down the current two-node cluster limit imposed by Windows NT.
Oracle has just completed a certification process for four-node NT clusters with more than 10 hardware vendors. And certification of more vendor hardware configurations and expansion to six-node Windows NT clusters is expected in the next 30 days.
Oracle already offers a two-node clustering solution for Windows NT called FailSafe. Also, Microsoft offers a two-node cluster solution for its customers with SQL Server 6.5, Enterprise Edition. In addition, IBM offers clustered support for its DB2 customers.
Although both rival products are solid, Parallel Server's multinode support not only offers greater redundancy, but also the capability to incrementally scale the database and execute database operations in parallel.
I recently spent time observing Parallel Server in action onsite at Oracle, in Redwood Shores, California. Though I didn't have the chance to perform the thorough testing necessary to judge Parallel Server, overall I was impressed with what I saw.
The test setup that I observed included a quartet of Data General AV3600 four-processor machines linked via 100Mbps interconnections with SCSI links to a shared Clariion disk array. With this test configuration running an order-entry system, I was able to see continued redundant operation when one of the nodes in the configuration was brought down.
I was impressed to see how Parallel Server was able to shift loads across multiple nodes to improve performance. Also, as new nodes were brought up the performance improvement was obvious.
Parallel Server uses distributed lock management and parallel caching to manage activity in multi-node settings. The Oracle database optimiser also can take advantage of all available processors in the cluster to increase execution performance during operations, such as running a large query.
The management tools that support Parallel Server are nicely integrated into the Oracle Enterprise Manager graphical interface. Real-time performance monitoring is available via predefined graphs.
The performance monitor does not yet support the creation of custom graphs by administrators, but according to Oracle officials the company plans to add that feature in an upcoming release. In this version there is no support for exporting performance data for use in other reporting tools. However, Oracle does have another add-on, called Capacity Planner, that supports greater reporting and exporting capabilities.
Higher-end sites running Oracle database applications in Windows NT settings should consider Parallel Server as an option for greater redundancy, growth, and performance. Although the number of nodes and certified hardware configurations is still maturing, Parallel Server technology offers strategic value for NT enterprise settings.
THE BOTTOM LINE: Very Good
Parallel Server for Windows NT
This add-on to the Oracle database lets high-end data warehouse, online transaction processing, and decision support sites go beyond the current two-node Windows NT cluster limit.
Pros: Offers greater scalability and better transaction performance at large sites; enables redundancy; parallel database operations.
Cons: Limited to certified cluster hardware; limited reporting capabilities.
Price: no pricing data available.
Platforms: Windows NT, Unix, and others.