eeClust Project Successfully Completed

The eeClust project (Energy-Efficient Cluster Computing), funded by the German Ministry of Education and Research under the call "HPC-Software für skalierbare Parallelrechner", was successfully completed in March 2012. The project partners were the University of Hamburg (coordinator), JSC, Dresden University of Technology (TUD/ZIH) and ParTec Cluster Competence Center GmbH. The goal of the project was to investigate the relation between the behaviour of parallel programs and the energy consumption of their execution on a compute cluster. Furthermore, the project aimed to reduce the energy consumption of the application by switching temporarily unused components to a lower power state.

In the project, a small test cluster with high-resolution power meters was procured by the University of Hamburg. This cluster consists of 5 nodes with Intel Nehalem and 5 nodes with AMD Opteron processors, thus enabling the possibilities and results of hardware power mode management to be studied for the dominant x86 architectures. To determine the phases of inactivity, the well-known performance analysis tools Vampir and Scalasca were used. At JSC, the Scalasca toolset was extended during the project to identify the energy-saving potential in wait states of an application.

An API was developed to manually instrument an application to communicate the required hardware resources to a system process. This daemon, also developed in the project, switches the unused hardware to a lower power state and back again and ensures that no component needed by another process is switched.

The tools and methods developed in the project are now being used and extended in other JSC projects, specifically in the Exascale Innovation Center (EIC), to efficiently manage large-scale machines. Further information on eeClust and a list of publications can be found at

A final workshop is planned in the context of the 3rd International Conference for Energy-Aware High-Performance Computing (EnA-HPC'12) in Hamburg in September, where the project partners will present the findings of the project.
(Contact: Michael Knobloch,

from JSC News No. 205, 15 June 2012

Last Modified: 09.09.2022