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<<TableOfContents>>
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= Overview =
General introduciton to initial GPE project can be found [[http://hpc.desy.de/gpe/|here]].



= GPU Hardware =
The current GPU system at DESY (Zeuthen) consists of a single [[http://www.supermicro.com/products/system/4U/7046/SYS-7046GT-TRF.cfm?GPU=FC4|server]] with dual nVidia Tesla C2050 GPU cards. It is hosted on gpu1 and is also used as a testbed for new developments in GPU-to-GPU networking with custom designed interconnects and InfiniBand.



= Environment =
Currently on the system the newest version of the [[http://developer.nvidia.com/cuda-toolkit-40|CUDA SDK 4.0]] alongside with device drivers and libraries are installed on gpu1. The Software Development Kit provides the following:

 * CUDA C/C++ Compiler
 * GPU Debugging & Profiling Tools
 * GPU-Accelerated Math Libraries
 * GPU-Accelerated Performance Primitives (Thrust library)
 * GPU-direct (under tests)



= GPU Benchmarks =
For evaluation and development a set of common benchmarks, as well as specially designed micro benchmarks were run on the gpu1 system.



== Low-level benchmarks ==
Custom designed benchmarks use OpenMPI and OpenMP for task parallelization and allocation on the host CPUs and evaluate the following performance metrics:

 * Bandwidth of host-ot-GPU memory copy operations
 * Bandwidth and latency of GPU-to-GPU communication
 * GPU-to-InfiniBand hardware datapath propagation delay


== Application-level benchmarks ==
For ensuring consistency of performance with real-world applications, the Scalable HeterOgeneous Computing ([[http://ft.ornl.gov/doku/shoc/start|SHOC]]) benchmark suite was run on the gpu1 system too. This benchmark suite gives not only benchmark results for CUDA implementations of key algorithms but also corresponding implementations of the more general OpenCL parallel programming framework.



= GPU Applications =
Recent applications utilizing the gpu1 system at DESY (Zeuthen) are [[http://usqcd.jlab.org/usqcd-docs/chroma/|Chroma]]-based LQCD munerical simulationd and applications from the field of Astro Particle Physics.