TY - JOUR A1 - Sagnol, Guillaume A1 - Schmidt genannt Waldschmidt, Daniel T1 - Restricted Adaptivity in Stochastic Scheduling JF - 29th Annual European Symposium on Algorithms (ESA 2021) N2 - We consider the stochastic scheduling problem of minimizing the expected makespan on m parallel identical machines. While the (adaptive) list scheduling policy achieves an approximation ratio of 2, any (non-adaptive) fixed assignment policy has performance guarantee Ω(logm/loglogm). Although the performance of the latter class of policies are worse, there are applications in which non-adaptive policies are desired. In this work, we introduce the two classes of δ-delay and τ-shift policies whose degree of adaptivity can be controlled by a parameter. We present a policy - belonging to both classes - which is an O(loglogm)-approximation for reasonably bounded parameters. In other words, an exponential improvement on the performance of any fixed assignment policy can be achieved when allowing a small degree of adaptivity. Moreover, we provide a matching lower bound for any δ-delay and τ-shift policy when both parameters, respectively, are in the order of the expected makespan of an optimal non-anticipatory policy. Y1 - 2021 U6 - https://doi.org/10.4230/LIPIcs.ESA.2021.79 VL - 204 SP - 79:1 EP - 79:14 ER -