Using memory in the Cedar system

  • Robert E. McGrath
  • Perry A. Emrath
Session 2: Parallel Architectures
Part of the Lecture Notes in Computer Science book series (LNCS, volume 297)


The design of the virtual memory system for the Cedar multiprocessor under construction at the University of Illinois is discussed. The Cedar architecture features a hierarchy of memory, some shared by all processors, and some shared by subsets of processors. The Xylem operating system is based on Alliant Computer Systems CONCENTRIXTM operating system, which is based on 4.2BSD UNIXTM. Xylem supports multi-tasking and demand paging of parts of the memory hierarchy into a linear virtual address space. Memory may be private to a task or shared between all the tasks. The locality and attributes of a page may be modified during the execution of a program. Examples of how these mechanisms can be used are discussed.


Global Memory Address Space User Program Memory Hierarchy Virtual Memory 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 1988

Authors and Affiliations

  • Robert E. McGrath
    • 1
  • Perry A. Emrath
    • 1
  1. 1.Center for Supercomputing Research and DevelopmentUniversity of Illinois at Urbana-ChampaignUrbanaUSA

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