The Philippine government's official weather service, PAGASA, has replaced its SGI supercomputer with a clustered Debian Linux system that can process information vital to protection against typhoons, floods, droughts, tsunamis and other wild weather conditions at a fraction of the cost.

The cluster includes eight PCs running as a single node, connected via a gigabit switch, each with dual 64-bit Intel Xeon processors running the Debian Linux OS.

"We tried several Linux flavours, including Red Hat, Mandrake, Fedora etc," said Alan Pineda, head of ICT and flood forecasting at PAGASA.

"Our ICT group came out with Debian as the most stable in servers, especially when things are being done pretty much in automatic mode. In our workstations the preference among programmers is Ubuntu, which is basically Debian-based," he said.

The major motivation for migrating to an open source based system was cost. Previously, for almost a decade PAGASA used an SGI Irix supercomputer that cost over P200,000 (AUD$5200) a month to run. Since September 2007, the Debian Linux cluster has dropped that monthly figure down to around P10,000 (AUD$260).

"The other motivation was to increase computing power with less capitilisation. With Irix, our capitilisation was about P25 million (AUD$655,000). With the Debian cluster we spent around P2 million (AUD$52,000) including the migration cost and training," Pineda said.

"It doesn't make a dent in our budget; it's very negligible."

Pineda said PAGASA also wanted to implement a system which is very scalable.

All in all PAGASA uses 32 clustered processors, with 16 devoted to R & D and 16 for operational purposes.