A performance comparison of homeless and home-based lazy release consistency protocols in software shared memory

In this paper, we compare the performance of two multiple-writer protocols based on lazy release consistency. In particular, we compare the performance of Princeton's home-based protocol and TreadMarks' protocol on a 32-processor platform. We found that the performance difference between the two protocols was less than 4% for four out of seven applications. For the three applications on which performance differed by more than 4%, the TreadMarks protocol performed better for two because most of their data were migratory, while the home-based protocol performed better for one. For this one application, the explicit control over the location of data provided by the home-based protocol resulted in a better distribution of communication load across the processors. These results differ from those of a previous comparison of the two protocols. We attribute this difference to (1) a different ratio of memory to network bandwidth on our platform and (2) lazy diffing and request overlapping, two optimizations used by TreadMarks that were not used in the previous study.

[1]  Anoop Gupta,et al.  Memory consistency and event ordering in scalable shared-memory multiprocessors , 1990, ISCA '90.

[2]  Anoop Gupta,et al.  SPLASH: Stanford parallel applications for shared-memory , 1992, CARN.

[3]  Anoop Gupta,et al.  Memory consistency and event ordering in scalable shared-memory multiprocessors , 1990, [1990] Proceedings. The 17th Annual International Symposium on Computer Architecture.

[4]  Liviu Iftode,et al.  Performance evaluation of two home-based lazy release consistency protocols for shared virtual memory systems , 1996, OSDI '96.

[5]  Alan L. Cox,et al.  An Evaluation of Software-Based Release Consistent Protocols , 1995, J. Parallel Distributed Comput..

[6]  Alan L. Cox,et al.  Lazy release consistency for software distributed shared memory , 1992, ISCA '92.

[7]  Mark D. Hill,et al.  A Unified Formalization of Four Shared-Memory Models , 1993, IEEE Trans. Parallel Distributed Syst..

[8]  Alan L. Cox,et al.  Software DSM protocols that adapt between single writer and multiple writer , 1997, Proceedings Third International Symposium on High-Performance Computer Architecture.