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Improved parallelization techniques for the density matrix renormalization group

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 نشر من قبل Julian Rincon
 تاريخ النشر 2009
  مجال البحث فيزياء
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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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