The annual Salesforce. com Dreamforce user event kicked off on Tuesday in San Francisco, with Salesforce’s chairman and CEO Marc Benioff taking a dig at rival Oracle and its CEO Larry Ellison.

Addressing the 14,000 keynote attendees, Benioff said that Larry Ellison’s favorite Exadata for cloud computing virtually fails the cloud test; and added that a genuine vision is apparently missing at Oracle.

Flashing an image of the Exadata server on stage, Benioff remarked: “The cloud is not in a box — you don't have to add more boxes to get scalability.”

Further deriding Oracle’s September-launched Solaris-based Exalogic Elastic Cloud, Benioff said that it was a step backwards to the world of mainframe computing running software that is paid for using a pricey license.

However, later at an executive session, Benioff clearly played down the intensifying competition between Salesforce and Oracle, and said: “Oracle is our ally. I honestly don't see us as a competitor with them. Larry and I have a friendly banter, but it is friendly.”

Meanwhile, the Dreamforce event was an explicit reflection of the fact that the Salesforce has enjoyed tremendous growth in its first 11 years. According to the figures shared by Benioff, there are 30,000 registered delegates for the event; though one of Salesforce’s marketing teams put the number of attendees at the conference at around 22,000.