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Graph Oracle Models, Lower Bounds, and Gaps for Parallel Stochastic Optimization

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 نشر من قبل Blake Woodworth
 تاريخ النشر 2018
  مجال البحث الهندسة المعلوماتية
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We suggest a general oracle-based framework that captures different parallel stochastic optimization settings described by a dependency graph, and derive generic lower bounds in terms of this graph. We then use the framework and derive lower bounds for several specific parallel optimization settings, including delayed updates and parallel processing with intermittent communication. We highlight gaps between lower and upper bounds on the oracle complexity, and cases where the natural algorithms are not known to be optimal.



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