Cache directory look-up re-use as conflict check mechanism for speculative memory requests

Ohmacht, Martin

Title: Cache directory look-up re-use as conflict check mechanism for speculative memory requests

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Abstract

In a cache memory, energy and other efficiencies can be realized by saving a result of a cache directory lookup for sequential accesses to a same memory address. Where the cache is a point of coherence for speculative execution in a multiprocessor system, with directory lookups serving as the point of conflict detection, such saving becomes particularly advantageous.

Inventors:: Ohmacht, Martin

Issue Date:: 2013-09-10

Research Org.:: International Business Machines Corp., Armonk, NY (United States)

Sponsoring Org.:: USDOE

OSTI Identifier:: 1093237

Patent Number(s):: 8533399

Application Number:: 12/984,252

Assignee:: International Business Machines Corporation (Armonk, NY)

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

Y - NEW / CROSS SECTIONAL TECHNOLOGIES Y02 - TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE Y02D - CLIMATE CHANGE MITIGATION TECHNOLOGIES IN INFORMATION AND COMMUNICATION TECHNOLOGIES [ICT], I.E. INFORMATION AND COMMUNICATION TECHNOLOGIES AIMING AT THE REDUCTION OF THIR OWN ENERGY USE

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G - PHYSICS G06 - COMPUTING G06F - ELECTRIC DIGITAL DATA PROCESSING
G06F9/3834 - {Maintaining memory consistency
G06F9/30087 - {Synchronisation or serialisation instructions}
G06F9/30043 - {LOAD or STORE instructions

Y - NEW / CROSS SECTIONAL TECHNOLOGIES Y02 - TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE Y02D - CLIMATE CHANGE MITIGATION TECHNOLOGIES IN INFORMATION AND COMMUNICATION TECHNOLOGIES [ICT], I.E. INFORMATION AND COMMUNICATION TECHNOLOGIES AIMING AT THE REDUCTION OF THIR OWN ENERGY USE
Y02D10/00 - Energy efficient computing

G - PHYSICS G06 - COMPUTING G06F - ELECTRIC DIGITAL DATA PROCESSING
G06F12/0815 - Cache consistency protocols
G06F9/30072 - {to perform conditional operations, e.g. using guard}

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DOE Contract Number:: B554331

Resource Type:: Patent

Resource Relation:: Patent File Date: 2011 Jan 04

Country of Publication:: United States

Language:: English

Subject:: 97 MATHEMATICS AND COMPUTING

Citation Formats


                    Ohmacht, Martin. Cache directory look-up re-use as conflict check mechanism for speculative memory requests.  United States: N. p., 2013. 
        Web.

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                    Ohmacht, Martin. Cache directory look-up re-use as conflict check mechanism for speculative memory requests.  United States.

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                    Ohmacht, Martin. Tue .  
        "Cache directory look-up re-use as conflict check mechanism for speculative memory requests".  United States.  https://www.osti.gov/servlets/purl/1093237.

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@article{osti_1093237,

  title        = {Cache directory look-up re-use as conflict check mechanism for speculative memory requests},

  author       = {Ohmacht, Martin},

  abstractNote = {In a cache memory, energy and other efficiencies can be realized by saving a result of a cache directory lookup for sequential accesses to a same memory address. Where the cache is a point of coherence for speculative execution in a multiprocessor system, with directory lookups serving as the point of conflict detection, such saving becomes particularly advantageous.},

  doi          = {},

  journal      = {},
number       = ,

  volume       = ,

  place        = {United States},

  year         = {2013},

  month        = {9}

}

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