Azul Systems, a start-up headed by former Sun executives, is offering appliances that promise to help customers adapt to rapidly changing Web-based workloads.

Azul's compute appliances are multi-core, multi-processor systems designed to take the compute-intensive load off busy application servers. The idea is to provide a pool of compute resources that can be tapped into by the application servers as needed.

Azul calls its approach network-attached processing, in which application servers have access to a pool of memory and compute resources. The company compares it to network-attached storage, in which servers tap into shared buckets of storage resources.

Azul originally focused on Java-based applications, rolling out its first Compute Appliance in April 2005. On Monday, Azul announced support for .Net applications, as well, through a partnership with Mainsoft, a company that converts .Net code to Java.

"Mainsoft takes files that are .Net and translates them into new files that are Java. That Java code can then be used on the Azul Compute Appliance just like any other Java code," says Shahin Khan, vice president and chief marketing officer at Azul.

Those .Net applications can expect throughput that is three times faster by tapping into the Azul Compute Appliance, Khan says. Perhaps more importantly, IT managers don't have to have idle hardware standing by to handle spikes in demand, because the .Net applications can now tap into the Azul compute pool and get additional memory and processing resources as needed.

Azul is working with Microsoft to provide native support for .Net, but for now the Mainsoft alliance will give .Net users earlier access to the Azul platform, Khan says.

He wouldn't say when Azul would support native .Net virtual machines. Java and .Net both use a virtual machine architecture, meaning that the application is separated from the hardware and can run on any platform, allowing processing-intensive workloads to be moved from traditional application servers to the Azul Compute Appliance.

With Azul proxy software installed on the application servers, Java processing can be offloaded to the Azul platform. The Mainsoft software encapsulates the .Net code into a Java virtual machine that can be shuttled to the Azul appliance. Users set policies directing how much processing power should be assigned to each application.