{"title":"The APOSTLE simulation language: granularity control and performance data","authors":"P. Wonnacott, D. Bruce","doi":"10.1145/238788.238833","DOIUrl":"https://doi.org/10.1145/238788.238833","url":null,"abstract":"A simulation-oriented language can significantly enhance the usability of Parallel Discrete Event Simulation (PDES) by hiding the complexities of the synchronization protocol used to ensure that events are processed in the correct order. The higher-level interface presented to the user by such a language also allows optimizations to be performed that are difficult and cumbersome with current parallel simulators, such as granularity control. APOSTLE is a new high-level simulation-oriented language for PDES, and in this paper we report that the APOSTLE granularity control mechanism reduced simulation run-times by as much as 80%. We also report that APOSTLE achieved a parallel speed-up of around 9 on 16 processors relative to its optimized sequential implementation and a parallel speed-up of around 6 on 16 processors relative to MODSIM II. Overall, we believe that the widespread success of PDES can only be achieved using a simulation-oriented language, and that APOSTLE has made a significant contribution towards this goal.","PeriodicalId":326232,"journal":{"name":"Proceedings of Symposium on Parallel and Distributed Tools","volume":"84 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114462854","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Conservative Circuit Simulation on Shared-Memory Multiprocessors","authors":"J. Keller, T. Rauber, B. Rederlechner","doi":"10.1145/238788.238835","DOIUrl":"https://doi.org/10.1145/238788.238835","url":null,"abstract":"We investigate conservative parallel discrete event simulations for logical circuits on shared-memory multiprocessors. For a first estimation of the possible speedup, we extend the critical path analysis technique by partitioning strategies. To incorporate overhead due to the management of data structures, we use a simulation on an ideal parallel machine (PRAM). This simulation can be directly executed on the SB-PRAM prototype, yielding both an implementation and a basis for data structure optimizations. One of the major tools to achieve these is the SB-PRAM's hardware support for parallel prefix operations. Our reimplementation of the PTHOR program on the SB-PRAM yields substantially higher speedups than before.","PeriodicalId":326232,"journal":{"name":"Proceedings of Symposium on Parallel and Distributed Tools","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114473563","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Massively Parallel Simulations of ATM Systems","authors":"K. Kumaran, B. Lubachevsky, A. Elwalid","doi":"10.1145/238788.238810","DOIUrl":"https://doi.org/10.1145/238788.238810","url":null,"abstract":"We simulate models of ATM communication systems on a massively parallel SIMD computer. Fast simulations of ATM models are needed because the regimes of interest usually involve high volumes of traffic and low failure rates. Unexpected practical and theoretical difficulties, partly due to the massive parallelism and SIMD aspects, were encountered and we show how to cope with them. In a replica-parallel simulation of an ATM system, large variations in computed statistics are caused by small differences in the distribution of employed random number generators. A comparison of these distributions using a secondary statistical measure served to disambiguate the results. It was also found that time-parallel simulations of ATM systems with Markov sources can be efficiently performed using parallel prefix methods only when the sources have a small number of states, while more complex sources require end-state matching for efficient simulation. We discovered that, with the proper choice of initial state distributions and partial regeneration points, the time and memory requirements can be much improved. Our simulations were carried out on the MasPar MP-1216 system with 16,384 processors, which was compared against an SGI workstation. We achieved about 60%-70% efficiency (speed-up of approx 35 compared to the ideal of approx 51).","PeriodicalId":326232,"journal":{"name":"Proceedings of Symposium on Parallel and Distributed Tools","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129022260","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"On Extending More Parallelism to Serial Simulators","authors":"D. Nicol, P. Heidelberger","doi":"10.1145/238788.238849","DOIUrl":"https://doi.org/10.1145/238788.238849","url":null,"abstract":"The Utilitarian Parallel Simulator (U.P.S.) extends parallelism to the CSIM sequential simulation tool by providing several new modeling constructs. Using conservative synchronization techniques, these constructs automatically support time-synchronized communications between CSIM submodels running on different processors. This paper describes extensions to U.P.S. that allow the user to assist U.P.S. by providing additional \"process lookahead,\" thereby reducing the frequency of synchronizations. The use and effect on performance of process lookahead is described for several models. In a mobile cellular communications model, the use of process lookahead results in up to a 60% improvement in speedup on 32 nodes of the IBM SP2. A factor of 3 improvement is obtained on a closed queueing network simulation running on 32 nodes of the Intel Paragon.","PeriodicalId":326232,"journal":{"name":"Proceedings of Symposium on Parallel and Distributed Tools","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116807496","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}