Online Algorithms for Parallel Job Scheduling and Strip Packing

We consider the online scheduling problem of parallel jobs on parallel machines, $P|online{−}list,m_j |C_{max}$. For this problem we present a 6.6623-competitive algorithm. This improves the best known 7-competitive algorithm for this problem. The presented algorithm also applies to the problem where machines are ordered on a line and only adjacent machines can be assigned to a job and, therefore, also to online orthogonal strip packing. Since previous results for these problems assume bounded job length, the presented algorithm is the first with a constant competitive ratio