多机仿真器SimDSM的设计及实现

仿真器是进行计算机体系结构研究的有力工具。本文以多机仿真器ＳｉｍＤＳＭ为实例,讨论了设计仿真器的一般原理和评价仿真器的标准,ＳｉｍＤＳＭ是为了分析研究分布式共享存储系统而设计的。它基于ＣＩＳＣ结构的Ｉｎｔｅｌ的体系结构,由于采用执行驱动和自定义的线程的实现方法,使得仿真可以高效准确进行。实验的结果表明,该仿真器具有较高的实用性和有效性。     

面向共享虚拟存储系统的编译支持的通信优化技术

当前的面向消息传递的自动并行编译器由于各种原因,只能支持极有限的一类数据并行应用程序,共享虚拟存储系统ＳＶＭ和面向共享存储的编译技术的相结合有效地解决了这一问题,使得编写并行应用程序变得十分容易,而且易于移植,然而,研究表明通信是影响基于ＳＶＭ的应用程序性能的主要因素之一。在文中,针对底层ＳＶＭ的特性,提出了页面对齐、软流水等编译支持的通信优化技术,在ＳＶＭ系统ＪＩＡＪＩＡ的平台上实现了制导辅助折     

Supporting flexible data distribution in software DSMs

Page-based software DSM systems suffer from false sharing caused by the large sharing granularity,and only support one-dimension Block or Cyclicblock data distribution schemes,Thus applications running on them will suffer from poor data locality and will be able to exploit parallelism only when using a large number of processors,In this paper.a way towards supporting flexible data distribution(FDD) on software DSM system is presented.Small granularity-tunable blocks,the size of which can be set by compiler or programmer,are used to overlap the working data sets distributed among processors.The FDD was implmented on a software DSM system called JIAJIA.Compared with Block/Cyclic-block distribution schemes used by most DSM systems now,experiments show that the proposed way of flexible data distribution is more effective.The performance of the applications used in the experiments is significantly improved.