Over the last three years MTU Aero Engines has built up two parallel Linux clusters which contain a total of 448 processors. MTU's supercomputer is now ranked at 179 in the Top500 supercomputers.
Axel Huedepohl, engineering systems manager at MTU, told ZDNet UK that the company used to use in-house multi-processor machines, and rent time from supercomputer centres. The company had also experimented with distributed computing, using the spare CPU cycles on the company's 600 Unix workstations. But Huedepohl found it was cheaper to run a Linux cluster as fewer software licences were required.
He estimates that moving the majority of the processing work to a Linux cluster has cut operational costs by over 70 percent. Huedepohl said the main reason for choosing a Linux cluster over the other options was to cut costs.
The company began exploring Linux three years ago when a student on a work placement linked up first four, then eight computers, to build a mini cluster. The first production cluster was completed a year later, and contained around 90 computers. The SuSE distribution of Linux was chosen for the server, partly because the company liked the support it offered.
Since then it has continued adding hardware to the cluster and is now running two clusters running in parallel -- one on Ethernet technology, the other based on Myrinet, an alternative network technology widely used for interconnecting clusters.
The Myrinet cluster runs 256 Xeon processors at 3.6GHz with 3GB of RAM. The Ethernet cluster runs 192 Xeon processors running at 2.4GHz with 3GB of RAM, according to Huedepohl.
The Linux cluster is mainly used to run an application which does complex three-dimensional simulations of the aerodynamics within engines. The main challenge that MTU faced with setting up the Linux cluster was setting up system administration.
"We invested a lot of work into automating the system administration into the computing infrastructure," said Huedepohl, "Once we had done that, the operation was easier and cheaper to run. We invested half a man year into automating this."
The Linux cluster cannot be used for running all the applications that are run at MTU due to memory limitations. Applications that need to calculate very large models need 64GB of memory in one single address space, which was not possible in the initial version of Linux that MTU used. Current versions of Linux allow this and MTU is now running tests on it.
Huedepohl hopes to increase the use of Linux in the future. He hopes that by the end of the year all applications will be run under Linux. The company is running tests to see if its administration systems, such as SAP, can be run on Linux.
After that, the next big goal for the company is Linux on the desktop. At the moment engineers use SGI or Sun workstations, but by the end of 2005 Huedepohl hopes that all engineers will be using Intel-based Linux workstations. The company has not decided yet whether to use Linux office productivity applications. It is building a lab to test this but Huedepohl thinks it is unlikely that it will be able to replace Windows completely as it uses 400 different Microsoft applications