Abstract
Page based software DSMs experience high degrees of false sharing especially in irregular applications with fine grain sharing granularity. The over-heads due to false sharing is considered to be the dominant factor limiting the performance of software DSMs. Several approaches have been proposed in the literature to reduce/eliminate false sharing. In this paper, we evaluate two of these approaches, viz., the Multiple Writer approach and Emulated Fine Grain Shar-ing (EmFiGS) approach. Our evaluation strategy is two pronged: firstly, we use a novel implementation independent analysis which uses overhead counts to com-pare the different approaches. The performance of EmFiGS approach is signifi-cantly worse, by a factor of 1.5 to as much as 90 times, compared to the Multiple Writer Approach. In many cases, EmFiGS approach performs worse that even a single writer lazy release protocol which experiences very high overheads due to false sharing. Our analysis shows that the benefits gained by eliminating false sharing are far outweighed by the performance penalty incurred due to the reduced exploitation of spatial locality in the EmFiGS approach. The implementation in-dependent nature of our analysis implies that any implementation of the EmFiGS approach is likely to perform significantly worse than the Multiple Writer ap-proach. Secondly, we use experimental evaluation to validate and complement our analysis. Experimental results match well with our analysis. Also the execu-tion times of the application follow the same trend as in our analysis, reinforcing our conclusions.
This work was done when the first author was a research student at the Department of Computer Science and Automation, Indian Institute of Science, Bangalore. This work was supported by research grants from IBM, Poughkeepsie, NY and IBM Solutions Research Centre, New Delhi, under IBM’s Shared University Program.
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References
Li, K., Hudak, P.: Memory coherence in shared virtual memory systems. In: Proc. of the 5th Annual ACM Symp. on Principles of Distributed Computing (PODC’86). (1986) 229–239
Bennett, J.K., Carter, J.B., Zwaenepoel, W.: Munin: Shared memory for distributed mem-ory multiprocessors. Technical Report COMP TR89-91, Dept. of Computer Science, Rice University (1989)
Torellas, J., Lam, M., Henessey, J.: False sharing and spatial locality in multiprocessor caches. IEEE Transactions on Computers 6 (1994) 651–663
Keleher, P., Cox, A.L., Zwaenepoel, W.: Lazy release consistency for software distributed shared memory. In: Proc. of the 19thAnnual Int’l Symp. on ComputerArchitecture (ISCA’92). (1992) 13–21
Amza, C., Cox, A.L., Dwarkadas, S., Keleher, P., Lu, H., Rajamony, R., Yu, W., Zwaenepoel, W.: TreadMarks: Shared memory computing on networks of workstations. IEEE Computer 29 (1996) 18–28
Keleher, P.: The CVM manual. Technical report, University of Maryland (1996)
Freeh, V.W., Andrews, G.R.: Dynamically controlling false sharing in distributed shared memory. In: Proc. of the Fifth IEEE Int’l Symp. on High Performance Distributed Computing (HPDC-5). (1996) 403–411
Itzkovitz, A., Schuster, A.: MultiViewand Millipage: Fine-grain sharing in page-based DSMs. In: Proc. of the 3rd Symp. on Operating Systems Design and Implementation (OSDI’99). (1999) 215–228
Keleher, P.: The relative importance of concurrent writers and weak consistency models. In: Proc. of the 16th Int’l Conf. on Distributed Computing Systems (ICDCS-16). (1996) 91–98
Adve, S.V., Gharachorloo, K.: Shared memory consistency models:Atutorial. IEEE Computer 29 (1996) 66–76
Amza, C., Cox, A.L., Dwarkadas, S., Zwaenepoel, W.: Software DSMprotocols that adapt be-tween single writer and multiple writer. In: Proc. of the 3rd IEEE Symp. on High-Performance Computer Architecture (HPCA-3). (1997) 261–271
Manjunath, K.V., Govindarajan, R.: Performance analysis of methods that overcome false sharing effects in software DSMs. Technical Report TR-HPC-08 /2001, Indian Institute of Science, Bangalore (2001) http://hpc.serc.iisc.ernet.in/Publications/kvm2001.ps
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Manjunath, K.V., Govindarajan, R. (2001). Hidden Costs in Avoiding False Sharing in Software DSMs. In: Monien, B., Prasanna, V.K., Vajapeyam, S. (eds) High Performance Computing — HiPC 2001. HiPC 2001. Lecture Notes in Computer Science, vol 2228. Springer, Berlin, Heidelberg. https://doi.org/10.1007/3-540-45307-5_26
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DOI: https://doi.org/10.1007/3-540-45307-5_26
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