Making lockless synchronization fast: performance implications of memory reclamation <font color=blue>[Best Paper Award]</font>

Thomas E. Hart, Paul E. McKenney, Angela Demke Brown

Proceedings of the 20th International Parallel and Distributed Processing Symposium (IPDPS), Rhodes Island, Greece, April 2006

 

Abstract

<p>Achieving high performance for concurrent applications on modern multiprocessors remains challenging. Many programmers avoid locking to improve performance, while others replace locks with non-blocking synchronization to protect against deadlock, priority inversion, and convoying. In both cases, dynamic data structures that avoid locking, require a memory reclamation scheme that reclaims nodes once they are no longer in use.</p> <p>&nbsp;</p> <p>The performance of existing memory reclamation schemes has not been thoroughly evaluated. We conduct the first fair and comprehensive comparison of three recent schemes—quiescent-state-based reclamation, epoch-based reclamation, and hazard-pointer-based reclamation—using a flexible microbenchmark. Our results show that there is no globally optimal scheme. When evaluating lockless synchronization, programmers and algorithm designers should thus carefully consider the data structure, the workload, and the execution environment, each of which can dramatically affect memory reclamation performance.</p>

 

Manuscript

Pdf

 

Bibtex

Bib