Some New Results on Liu’s Conjecture
نویسنده
چکیده
Consider the problem of scheduling n tasks with precedence constraint ≺ on m parallel processors so as to minimize the makespan. Let ω and ω′ be the makespans of the optimal nonpreemptive and optimal preemptive schedules, respectively. Liu’s conjecture states that ω ω′ ≤ 2m m+1 . In this paper, we present a simple proof of the conjecture for ≺= ∅, and give an improved bound closer to that in the conjecture than the previously proved bound for arbitrary ≺.
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تاریخ انتشار 2011