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Scheduling with Communication Delay in Near-Linear Time

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 نشر من قبل Quanquan C. Liu
 تاريخ النشر 2021
  مجال البحث الهندسة المعلوماتية
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We consider the problem of efficiently scheduling jobs with precedence constraints on a set of identical machines in the presence of a uniform communication delay. In this setting, if two precedence-constrained jobs $u$ and $v$, with ($u prec v$), are scheduled on different machines, then $v$ must start at least $rho$ time units after $u$ completes. The scheduling objective is to minimize makespan, i.e. the total time between when the first job starts and the last job completes. The focus of this paper is to provide an efficient approximation algorithm with near-linear running time. We build on the algorithm of Lepere and Rapine [STACS 2002] for this problem to give an $Oleft(frac{ln rho}{ln ln rho} right)$-approximation algorithm that runs in $tilde{O}(|V| + |E|)$ time.

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