Reader set encoding for directory of shared cache memory in multiprocessor system

Ahn, Dnaiel; Ceze, Luis H.; Gara, Alan; Ohmacht, Martin; Xiaotong, Zhuang

Title: Reader set encoding for directory of shared cache memory in multiprocessor system

Abstract

In a parallel processing system with speculative execution, conflict checking occurs in a directory lookup of a cache memory that is shared by all processors. In each case, the same physical memory address will map to the same set of that cache, no matter which processor originated that access. The directory includes a dynamic reader set encoding, indicating what speculative threads have read a particular line. This reader set encoding is used in conflict checking. A bitset encoding is used to specify particular threads that have read the line.

Inventors:: Ahn, Dnaiel; Ceze, Luis H.; Gara, Alan; Ohmacht, Martin; Xiaotong, Zhuang

Issue Date:: 2014-06-10

Research Org.:: International Business Machines Corporation, Armonk, NY (USA)

Sponsoring Org.:: USDOE

OSTI Identifier:: 1134016

Patent Number(s):: 8751748

Application Number:: 13/008,583

Assignee:: International Business Machines Corporation

Patent Classifications (CPCs):: G - PHYSICS G06 - COMPUTING G06F - ELECTRIC DIGITAL DATA PROCESSING

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G - PHYSICS G06 - COMPUTING G06F - ELECTRIC DIGITAL DATA PROCESSING
G06F9/524 - {Deadlock detection or avoidance}
G06F12/08 - in hierarchically structured memory systems, e.g. virtual memory systems

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DOE Contract Number:: B554331

Resource Type:: Patent

Country of Publication:: United States

Language:: English

Subject:: 97 MATHEMATICS AND COMPUTING

Citation Formats


                    Ahn, Dnaiel, Ceze, Luis H., Gara, Alan, Ohmacht, Martin, and Xiaotong, Zhuang. Reader set encoding for directory of shared cache memory in multiprocessor system.  United States: N. p., 2014. 
        Web.

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                    Ahn, Dnaiel, Ceze, Luis H., Gara, Alan, Ohmacht, Martin, & Xiaotong, Zhuang. Reader set encoding for directory of shared cache memory in multiprocessor system.  United States.

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                    Ahn, Dnaiel, Ceze, Luis H., Gara, Alan, Ohmacht, Martin, and Xiaotong, Zhuang. Tue .  
        "Reader set encoding for directory of shared cache memory in multiprocessor system".  United States.  https://www.osti.gov/servlets/purl/1134016.

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@article{osti_1134016,

  title        = {Reader set encoding for directory of shared cache memory in multiprocessor system},

  author       = {Ahn, Dnaiel and Ceze, Luis H. and Gara, Alan and Ohmacht, Martin and Xiaotong, Zhuang},

  abstractNote = {In a parallel processing system with speculative execution, conflict checking occurs in a directory lookup of a cache memory that is shared by all processors. In each case, the same physical memory address will map to the same set of that cache, no matter which processor originated that access. The directory includes a dynamic reader set encoding, indicating what speculative threads have read a particular line. This reader set encoding is used in conflict checking. A bitset encoding is used to specify particular threads that have read the line.},

  doi          = {},

  journal      = {},
number       = ,

  volume       = ,

  place        = {United States},

  year         = {2014},

  month        = {6}

}

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Works referenced in this record:

Bulk Disambiguation of Speculative Threads in Multiprocessors
conference, January 2006

Ceze, L.; Tuck, J.; Torrellas, J.
33rd International Symposium on Computer Architecture (ISCA'06)
https://doi.org/10.1109/ISCA.2006.13

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Title: Reader set encoding for directory of shared cache memory in multiprocessor system

Abstract

Citation Formats

Bulk Disambiguation of Speculative Threads in Multiprocessors conference, January 2006

Bulk Disambiguation of Speculative Threads in Multiprocessors
conference, January 2006