The database giant highlighted testimonies from a handful of companies that are using the technology, and unveiled partnerships with server manufacturers designed to make it easier for customers to deploy the technology.
Introduced in June with the launch of Oracle 9i, the clustering feature lets customers install a database across two or more servers linked together.
"The benefit of a clustered system is that you can add or take away nodes as your needs dictate," said Carl Olofson, programme director at analyst firm IDC. "High availability is also key because of the pressures to build computer systems that are available all day."
Oracle admits that customers have been slow to adopt clustering, partly because they are afraid of the complexity. The company's first attempt at the technology, delivered in 1997 with Oracle 8i, was hard to manage and did not offer the transactional processing performance some customers needed, acknowledged Ken Jacobs, Oracle's vice-president for server technologies.
However, Oracle thinks it has got it right this time, and the company spotlighted a handful of customers that have decided to use Real Application Clusters.
Acxiom, which manages data warehouses for banks, retailers and other businesses, turned to 9i's clustering to reduce server downtime and improve the availability of its customers' data, said Tim Donar, Acxiom's senior systems architect.
The company began clustering in 1997 with Oracle 8i and recently implemented the latest version on two Compaq servers, each populated with about 20Tbytes of data, he said.
"We ran some of the standard data warehousing tests and saw about a 38% improvement in performance [with Oracle 9i over Oracle 8.17]," Donar said.
FreeMarkets, which hosts online marketplaces for buyers and sellers, tested the 9i clustering feature for two months and went live with it in November.
The switch helped reduce the time it takes to failover from one server to the next by about two seconds, down to three or four seconds, said FreeMarkets vice-president John Benzinger.
Vector SCM, a subsidiary of General Motors that manages the car maker's supply chain infrastructure, will switch to Real Application Clusters early in 2002 because it sees it as a way to add capacity using relatively low-cost servers.
The company expects the switch to bring it about £1m in hardware savings, according to David Brown, Vector's integration and emerging technologies architect.
Despite the customers lined up here, Olofson said it was too early to say if the benefits of Real Application Clusters will be as great as Oracle claims. It is also too soon to say whether Oracle's "shared-disk" method of clustering servers will serve customers better than the "shared-nothing" approach being pursued by IBM, NCR, Microsoft and others, he said.
The different approaches have to do with how data is stored across a cluster. "Shared nothing tends to be more appropriate for use with large, complex databases where you have a lot of unpredictable queries, such as data warehousing," Olofson said.
On the other hand, Oracle's shared-disk approach typically favours environments that support a high volume of transactions occurring quickly, like those performed by e-commerce applications and other Internet business software.
"I think what Oracle is betting on is that there's going to be a growing need for systems that provide transaction processing support for these types of Internet applications," Olofson said.
Real Application Clusters are benefiting from a dramatic reduction in the cost of hardware components, as much as Oracle's technological developments, said Olofson. Price cuts are making it far more economically viable for even medium-sized companies to build clusters, he said.
Oracle is pushing clustering because it sees it as a way to differentiate its database from IBM and its other rivals, Olofson said. Oracle claims it is the only vendor to support clustering "out of the box" for business applications from SAP, Siebel Systems and PeopleSoft.
IBM refuted the claim and said it has also worked with those vendors to allow their applications to run in clustered environments using the company's DB2 database. "Oracle seems to be the only one who thinks shared nothing is bad," said Jeff Jones, director of strategy with IBM's data management solutions group.
To make it easier for companies to get up and running with a clustered system, Oracle announced on 3 December partnerships with Dell and Sun. Both will offer customers pre-configured and pre-tested systems running Oracle's clustering software.
Sun will offer the technology with its Sun Fire 280R servers and Storedge T3 arrays through value-added resellers starting later in December, the company said. Dell will offer the clustering software on pre-tested servers running Windows and Linux in the US from January, with a worldwide offering to follow.
Oracle already announced a similar partnership with Compaq earlier in 2001.