Changes between Version 8 and Version 9 of Projects/Performance-Modelling


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Timestamp:
03/09/13 20:00:23 (6 years ago)
Author:
annette
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  • Projects/Performance-Modelling

    v8 v9  
    1818Using a simple shallow water code to simulate some of the execution patterns of a sophisticated climate model, we have been exploring a benchmark driven performance modelling approach to evaluate runtime choices. Benchmarking allows for rapid development of a model without explicitly representing complex features of the hardware, although it does require the application to exist and be runnable on the target machine. It is hoped that this approach will provide an alternative to the expensive and time consuming testing of models by trial to find the ideal configuration of architectural parameters for best performance.  
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    20 The model has been successfully used to replicate weak and strong scaling experiments up to 16,000 cores and has been used to explore MPI rank to physical core mapping strategies on a Cray XE6 machine with Gemini interconnect and AMD Interlagos processors. Current work is underway to evaluate the modelling technique by repeating this work on an IBM Power 7 and IBM !BlueGene/Q. 
     20The model has been successfully used to replicate weak and strong scaling experiments up to 16,000 cores and has been used to explore MPI rank to physical core mapping strategies on a Cray XE6 machine with Gemini interconnect and AMD Interlagos processors. In the figure below the model correctly predicts a custom rank mapping that minimises off-node transfers will give a lower communication time that the default SMP-style mapping or a round-robin mapping.  
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     22[[Image(comms_model_affinity.jpg)]] 
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     24Current work is underway to evaluate the modelling technique by repeating this work on an IBM Power 7 and IBM !BlueGene/Q. 
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    2226'''Paper:''' A. Osprey, G. D. Riley, M. Manjunathaiah, and B. N. Lawrence. "A Benchmark-Driven Modelling Approach for Evaluating Deployment Choices on a Multicore Architecture". Proceedings of the International Conference on Parallel & Distributed Processing Techniques & Applications. 2013. [http://home.badc.rl.ac.uk/lawrence/static/2013/05/27/OspEA14.pdf pdf]