InfoVista has claimed a breakthrough in capacity planning for virtualised servers. It said its latest VistaInsight for Servers management software can accurately size both physical and virtual servers, making it much easier for managers to plan server consolidation.

The key is its ability to report resource usage on any type of server and model how applications would run in a different environment, for example if they were moved from a physical server to a virtual one.

"Our previous release was able to manage virtual servers as you would any other server, but this new release - version 3 - goes way beyond that, in particular by mapping the virtual resources to the underlying physical resources," said Beth Ruck, InfoVista's senior product marketing manager for enterprise solutions.

The aim, she said, is to help managers decide which physical servers can be virtualised and consolidated. For instance, the software can report resource usage across a group of servers and suggest which of the physical machines would be the best host to run the others as virtual machines.

"In order to know what you can virtualise, you have got to have historical visibility into how your applications have performed and how they used system resources," Ruck added. "Different applications of course use server resources differently - some use a lot of memory, or a lot of CPU, without that signalling a problem. You need to understand that, prior to virtualisation."

InfoVista said that VistaInsight can collect, store and consolidate data from hundreds or thousands of servers. More importantly, it can normalise the data so it can be compared accurately, even across different hardware, operating systems and virtualisation technologies.

"One of the things we do is some unique calculations of what the overall horsepower on a physical resource is - the way we calculate horsepower and server saturation is quite different from what the server manufacturers do," Ruck said. "Firstly, you have to be able to calculate the raw horsepower, and secondly ou need to have a normalised calculation of saturation."

She said that the only thing the software cannot yet do is automatically calculate how much horsepower a server will produce once it has been virtualised.

"You still have to understand how your virtualisation product - VMWare, say - is going to affect performance by adding in a figure to represent the overhead from virtualisation," she said. "But the rest of the calculations are done in the background."