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arXiv · 0909.5662

Improved parallelization techniques for the density matrix renormalization group

Julian Rincon·D. J. Garcia·K. Hallberg
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Abstract

A distributed-memory parallelization strategy for the density matrix renormalization group is proposed for cases where correlation functions are required. This new strategy has substantial improvements with respect to previous works. A scalability analysis shows an overall serial fraction of 9.4% and an efficiency of around 60% considering up to eight nodes. Sources of possible parallel slowdown are pointed out and solutions to circumvent these issues are brought forward in order to achieve a better performance.

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Julian Rincon, D. J. Garcia, K. Hallberg. 2010-04-18. Improved parallelization techniques for the density matrix renormalization group. https://doi.org/10.1016/j.cpc.2010.03.018

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