Azul Systems Inc. is doubling the capacity of its "computing appliance," a device that uses multiple multicore processors and is a departure from the typical server-based approach to large scale computing.

Azul Thursday is scheduled to launch two new models of its Vega 2 computing appliances that feature up to 16 chips with a total 768 cores for running Java software applications. Rather than add more servers with dual- or quad-core chips as computing needs grow, Azul describes its product as a pool of processing power that applications can dip into as needed. The company calls it "network-attached processing," because of its similarity to network-attached storage.

Besides the Vega 2 7280, Azul is also launching the model 7240 with eight chips and a total 384 cores. This follows the December 2006 launch of the Vega 2 3210 with two chips and 96 cores and the 3220 with 4 chips and 192 cores.

Network-attached processing is more energy-efficient than the multiple servers that would be needed to deliver the same performance, said Stephen DeWitt, CEO of the 5-year-old firm. He compares the concept to that of an electric utility.

"Imagine, if you will, in New York City trying to power every light, toaster or refrigerator with a battery. It's incredibly inefficient. Instead, what everyone does is tap into a big [electrical] grid," De Witt said.

In an Azul system, one server could be loaded with multiple Java applications and would connect to the appliance to do the processing.

Azul is taking a contrarian approach to delivering processing power, said Cal Braunstein, CEO of the research firm Robert Frances Group.

Azul processors act as attached processors to the server and only handle the Java code, Braunstein explained, which allows the server processors to perform more work by shifting the Java execution to the Azul appliance.

Although Azul's approach shares similarities with IBM Corp. mainframe computers, there are also important differences. "Azul's model is unique," Braunstein said in an e-mail interview. "I am not aware of any other companies pursuing this particular model."

But since Azul is new and small, big companies that could use it may be reluctant to buy technology they're not familiar with, he said.

An Azul Vega 2 is running part of the network at Pegasus Solutions Inc., a company that provides the back-end technology for making hotel reservations through online travel sites, hotels and travel agencies. The Azul system easily handles the workload of nine servers, said Steve Lapekas, chief technology officer for Pegasus.

"I can't get the box to sweat," Lapekas said.

Pegasus limits its use of Azul to a portion of its data center, though he said it may expand its use elsewhere.

DeWitt and the founders of Azul started the company after leaving Sun Microsystems Inc. The two companies are embroiled in a patent dispute dating back to March 2006 in which Sun accuses Azul executives of taking Sun's patented technology with them to start Azul. A lawsuit is still pending in U.S. District Court for the Northern District of California, DeWitt said.