Locality-Aware Many-Core Garbage Collection

The wide-scale deployment of multi-core and many-core processors will necessitate fundamental changes to garbage collectors. Highly parallel garbage collection is critical to the performance of these systems — today’s garbage collectors can quickly become the bottleneck for parallel programs. These processors will present additional new challenges — many contain non-uniform memory architectures in which some cores have faster access to certain regions of memory than other regions. This paper presents a new cache-aware approach to garbage collection. Our collector balances the competing concerns of data locality and heap utilization to improve performance. We have implemented our garbage collector and present results on a 64-core TILEPro64 processor. Our cache-aware parallel collector speeds up garbage collection by up to 46.7×.