Workshop on Parallel and Distributed Simulation最新文献

{"title":"Improved parallel architectural simulations on shared-memory multiprocessors","authors":"P. Konas, P. Yew","doi":"10.1145/182478.182584","DOIUrl":"https://doi.org/10.1145/182478.182584","url":null,"abstract":"In recent years, advances in technology and in the area of computer architecture have resulted in increasingly more complex designs. As the complexity of the designs increases, simulation becomes the only viable method for gaining insight into the operation of new as well as existing computer systems. One way to meet the excessive processing requirements of detailed computer systems simulations is to execute them on a multiprocessor machine. Computer systems simulations are inherently synchronous and contain significant amounts of inherent parallelism [8]. Hence, the main problem in such simulations is to exploit the available parelelism with the least possible overhead. Unfortunately, both conservative and optimistic asynchronous methods are not appropriate for such simulations because they introduce significant overheads in their attempt to find parallelism [8]. Therefore, we focus our attention on synchronous parallel simulation methods. In this paper we present a synchronous, parallel, event-driven approach (SPSDES). It differs from previous approaches in many ways: (1) it contains a single, global synchronization operation per simulation phase; (2) it introduces a minimum number of kernel operations into the simulation; (3) it allows for efficient processor self-scheduling; and (4) it aggressively exposes parallelism only when a simulation phase does not contain enough parallelism for the processors to exploit. We study the performance of SPaDES by simulating a symmetric multiprocessor (tat-get machine) on a NUMA multiprocessor (hosl machine). The NUMA characteristics of the host machine enable us to study the performance of the method under demanding run-time conditions and to assess the impact of partitioning and scheduling on the efficiency of the parallel simulator. The few kernel operations introduced by SPaDES, the use of a single barrier during each phase, and the exploitation of coarse-grain parallelism are the main reasons SPaDES achieves high performance. Our main concern in this paper is the performance of the proposed method in the simulation of synchronous architectural designs. In Section 2 we present the SPaDES simulation method, and in Section 3 we study its performance, Section 4 contains our conclusions and future research directions.","PeriodicalId":194781,"journal":{"name":"Workshop on Parallel and Distributed Simulation","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1994-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125514667","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":"Parallel proximity detection and the distribution list algorithm","authors":"J. Steinman, F. Wieland","doi":"10.1145/182478.182479","DOIUrl":"https://doi.org/10.1145/182478.182479","url":null,"abstract":"Generalized proximity detection for moving objects in a logically correct parallel discrete-event simulation is an interesting and fundamentally challenging problem. Determining who can see whom in a manner that is fully scalable in terms of CPU usage, number of messages, and memory requirements is highly non-trivial.\u0000A new scalable approach has been developed to solve this problem. This algorithm, called The Distribution List, has been designed and tested using the object-oriented Synchronous Parallel Environment for Emulation and Discrete-Event Simulation (SPEEDES) operating system. Preliminary results show that the Distribution List algorithm achieves excellent parallel performance.","PeriodicalId":194781,"journal":{"name":"Workshop on Parallel and Distributed Simulation","volume":"48 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1994-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122597572","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":"Discrete-event simulation and the event horizon","authors":"J. Steinman","doi":"10.1145/182478.182490","DOIUrl":"https://doi.org/10.1145/182478.182490","url":null,"abstract":"The event horizon is a very important concept that is useful for both parallel and sequential discrete-event simulations. By exploiting the event horizon, parallel simulations can process events in a manner that is risk-free (i.e., no antimessages) in adaptable “breathing” time cycles with variable time widths. Additionally, exploiting the event horizon can greatly reduce the event list management overhead that is common to virtually all discrete-event simulations.\u0000This paper develops an analytic model describing the event horizon from first principles using equilibrium considerations and the hold model (where each event, when consumed, generates a single new event with future-time statistics described by a known probability function). Exponential and Beta-density functions are used to verify the mathematics presented in this paper.","PeriodicalId":194781,"journal":{"name":"Workshop on Parallel and Distributed Simulation","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1994-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115873829","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":"Effect of communication overheads on Time Warp performance: an experimental study","authors":"C. Carothers, R. Fujimoto, P. England","doi":"10.1145/182478.182578","DOIUrl":"https://doi.org/10.1145/182478.182578","url":null,"abstract":"This paper describes results of an empirical study to evaluate the effect of communications delays on the performance of the Time Warp mechanism in order to assess the effectiveness of Time Warp in distributed computing environments. An implementation of Time Warp on a collection of networked workstations is used in this study. Performance using synchronous and asynchronous message passing primitives are compared, and it is observed that Time Warp experiences much more rolled back computation when using the synchronous primitives for certain applications. Message passing is decomposed into a computation component at the sender and receiver processors, and a transmission delay component that represents the amount of time the message remains “in transit” within the network. The effect of each of these components on Time Warp performance is studied. It is observed that communications latency in distributed computing environments can significantly degrade the efficiency of Time Warp for applications containing large numbers of simulator objects with small event granularity (by increasing the amount of rolled back computation), particularly applications using “self-driving” simulator objects. However, for applications containing large grained events, communication delay appears to have little effect on rollback behavior in Time Warp.","PeriodicalId":194781,"journal":{"name":"Workshop on Parallel and Distributed Simulation","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1994-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116581561","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":"An evaluation system for distributed-time VHDL simulation","authors":"A. Costa, A. De Gloria, P. Faraboschi, M. Olivieri","doi":"10.1145/182478.182582","DOIUrl":"https://doi.org/10.1145/182478.182582","url":null,"abstract":"Performance of VHDL simulation is a critical issue in electronic circuit design and is hard to achieve due to the complexity of the language and the different abstraction levels.\u0000This paper presents a system for performance evaluation of distributed-time VHDL simulation based on the analysis of simulation traces. The system allows to model different architectures, interconnection topologies and simulation algorithms. The main tools are a VHDL analyzer to extract dependencies, and a trace-driven simulator to evaluate the execution time on a given architecture.","PeriodicalId":194781,"journal":{"name":"Workshop on Parallel and Distributed Simulation","volume":"76 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1994-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134466570","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":"Adaptive checkpointing in Time Warp","authors":"R. Rönngren, R. Ayani","doi":"10.1145/182478.182577","DOIUrl":"https://doi.org/10.1145/182478.182577","url":null,"abstract":"In Time Warp optimistic discrete event simulation, there exists a need to occasionally save the states of the logical processes. The state saving often constitutes a substantial overhead. However it is not necessary to save each state of a logical process since states can be restored from earlier states by re-executing intermediate events. In this paper, we analyse the effects of doing the state saving less frequently and present a method that allows each logical process to adapt its state saving interval to its rollback behaviour. Experimental results indicate that the proposed method improves performance of the Time Warp system.","PeriodicalId":194781,"journal":{"name":"Workshop on Parallel and Distributed Simulation","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1994-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123464900","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":"The pessimism behind optimistic simulation","authors":"G. Varghese, R. Chamberlain, W. Weihl","doi":"10.1145/182478.182579","DOIUrl":"https://doi.org/10.1145/182478.182579","url":null,"abstract":"In this paper we make an analogy between the time that storage must be maintained in an optimistic simulation and the blocking time in a conservative simulation. By exploring this analogy, we design two new Global Virtual Time (GVT) protocols for Time Warp systems. The first protocol is based on null message clock advancement in conservative approaches. Our main contribution is a new protocol inspired by Misra's circulating marker scheme for deadlock recovery. It is simple enough to be implemented in hardware, takes no overhead in the normal path, can be made to work over non-FIFO links, and its overhead can be dynamically tuned based on computational load.","PeriodicalId":194781,"journal":{"name":"Workshop on Parallel and Distributed Simulation","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1994-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127162496","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":"Understanding supercritical speedup","authors":"Michial Gunter","doi":"10.1145/182478.182523","DOIUrl":"https://doi.org/10.1145/182478.182523","url":null,"abstract":"Simulations running under Time Warp using lazy cancellation can beat the bound given by the critical path. We explain this phenomenon to be the result of a kind of intra-object parallelism. Specifically, we show that instances of beating the critical path, called supercritical speedup, are made possible by messages that are independent of some event which precedes the message. This insight leads to a new definition for the critical path which is a tighter lower bound on Time-Warp simulations using lazy cancellation than any previously proposed. These results suggest criteria for choosing between lazy and aggressive cancellation.","PeriodicalId":194781,"journal":{"name":"Workshop on Parallel and Distributed Simulation","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1994-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130203345","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":"Parallel simulation of a high speed LAN","authors":"R. Rönngren, H. Rajaei, A. Popescu, M. Liljenstam, Y. Ismailov, R. Ayani","doi":"10.1145/182478.182580","DOIUrl":"https://doi.org/10.1145/182478.182580","url":null,"abstract":"Simulation of communication networks is often time consuming. Parallel simulation may be used to reduce the execution time of such a simulator. However, efficient modeling and simulation of such complex applications is not a trivial task. In this paper, we discuss the results of simulating a multigigabit/s network using both an optimistic and a conservative scheme. Our experimental result on a shared memory multiprocessor indicates that the conservative approach is superior to the optimistic one for this application.","PeriodicalId":194781,"journal":{"name":"Workshop on Parallel and Distributed Simulation","volume":"117 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1994-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131264049","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":"Parallel discrete event simulation: a modeling methodological perspective","authors":"E. Page, R. Nance","doi":"10.1145/182478.182536","DOIUrl":"https://doi.org/10.1145/182478.182536","url":null,"abstract":"The field of parallel discrete event simulation is entering a period of self-assessment. Fifteen years of investigation has seen great strides in techniques for efficiently executing discrete event simulations on parallel and distributed machines. Still, the discrete event simulation community at large has failed to recognize much of these results. One reason for this is perhaps a disagreement in the focus and purpose of the parallel discrete event simulation research community (primarily computer scientists) and the discrete event simulation community (a widely diverse group including operations researchers, statisticians, as well as computer scientists). An examination of the parallel discrete event simulation problem from a modeling methodological perspective illustrates some of these differences and reveals potentials for their resolution.","PeriodicalId":194781,"journal":{"name":"Workshop on Parallel and Distributed Simulation","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1994-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131317599","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}