Fastest computer cluster in Berlin-Brandenburg
Science Minister Sabine Kunst unveils new Datura high performance computing cluster at the Albert Einstein Institute
2400 processors, 200 servers, 4.8 TeraByte disc space and a maximum computing performance of 25.5 TeraFlops – which equals 25,500 billion calculating operations per second: these are some of the qualities of the Datura high performance computer, which will now help scientists at the Max Planck Institute for Gravitational Physics (Albert Einstein Institute/AEI) to calculate the collisions of black holes and neutron stars.
Architecture of the cluster computer
Datura is a high performance Linux computing cluster with a calculated maximum performance of 25.5 TeraFlops. Flops are floating point operations per second: they are a measurement for the speed of the cluster computer.
The cluster consists of 200 compute nodes, with respectively two Intel XEON X5650 Westmere processors with a clock speed of 2.66 GHz each, as well as a capacity of 24 GB RAM and 300 GB local memory. Six storage nodes with an available total capacity of 192 TB store the enormous amount of resulting data of the numerical simulation computations in a parallel file system (LUSTRE). A head node enables users to communicate with the cluster and serves as a management basis for the entire system. Alternatively, three networks are responsible for the communication of the individual computers amongst one another. Each of these networks fulfils its own very particular task.
At the heart of the high performance cluster is the network and thus the corresponding switch (Voltaire Grid Director 4700), which takes care of interprocess communication and the linkage of the storage components. In this case it is an Infiniband switch with a bandwidth of up to 51.8 Tbit/sec. The other two networks serve the system administration of the cluster.
As typical numerical simulations take several days or even weeks, the jobs are administered through a batch system. A user logs in at the head node in order to compile programme codes or have the primarily graphically depicted results displayed. An extremely important element for all computing tasks by scientists at the AEI is carried out by the CACTUS-Code, which was developed at the AEI. This is a flexible range of tools that allow all scientists to formulate problems in a computer-compatible manner and to have the calculations carried out.