Experimental analysis of space-bounded schedulers
Harsha Vardhan Simhadri, Guy E. Blelloch, Jeremy T. Fineman, Phillip B. Gibbons, Aapo Kyrola · 2014
The running time of nested parallel programs on shared memory machines depends in significant part on how well the scheduler mapping the program to the machine is optimized for the organization of caches and processors on the machine. Recent work proposed ``space-bounded schedulers'' for scheduling such programs on the multi-level cache hierarchies of current machines. The main benefit of this class of schedulers is that they provably preserve locality of the program at every level in the hierarchy, resulting (in theory) in fewer cache misses and better use of bandwidth than the popular work-stealing scheduler. On the other hand, compared to work-stealing, space-bounded schedulers are inferior at load balancing and may have greater scheduling overheads, raising the question as to the relative effectiveness of the two schedulers in practice.