Work Files Saved Searches
   My Account                                                  Search:   Quick/Number   Boolean   Advanced   Derwent    Help   


 The Delphion Integrated View

  Buy Now:   Buy PDF- 28pp  PDF  |   File History  |   Other choices   
  Tools:  Citation Link  |  Add to Work File:    
  View:  Expand Details   |  Jump to: 
  Go to:  Derwent  
 Email this to a friend  Email this to a friend 
       
Title: US7363432: Method and apparatus for directory-based coherence with distributed directory management
[ Derwent Title ]


Country: US United States of America

View Images High
Resolution

 Low
 Resolution

 
28 pages

 
Inventor: Gschwind, Michael Karl; Chappaqua, NY, United States of America
Johns, Charles Ray; Austin, TX, United States of America
Truong, Thoung Quang; Austin, TX, United States of America

Assignee: International Business Machines Corporation, Armonk, NY, United States of America
other patents from INTERNATIONAL BUSINESS MACHINES CORPORATION (280070) (approx. 44,393)
 News, Profiles, Stocks and More about this company

Published / Filed: 2008-04-22 / 2004-03-25

Application Number: US2004000809581

IPC Code: Advanced: G06F 13/00;

U.S. Class: 711/145; 711/141; 711/147;

Field of Search: Non/00e

Priority Number:
2004-03-25  US2004000809581

Abstract:     A system for cache coherency comprises a memory. The memory comprises a plurality of data items and a plurality of directory information items, each data item uniquely associated with one of the plurality of directory information items. Each of the plurality of data items is configured in accordance with one of a plurality of access modes. Each of the plurality of directory information items comprises indicia of the access mode of its associated data item. A multiplexer couples to the memory and comprises a multiplex ratio. A plurality of buffers couple to the multiplexer and to the memory. The multiplex ratio is a function of the number of buffers in the plurality of buffers. A plurality of multiplexer/demultiplexers (MDMs) each uniquely couple to a different one of the plurality of buffers. A plurality of processing elements couple to the memory; each of the processing elements uniquely couples in a point-to-point connection to a different one of the plurality of MDMs. Each of the processing elements is configured to transmit a data request to its associated MDM, the data request identifying one of the plurality of data items and an access mode. The memory is configured to transmit a data response to each of the processing elements in response to a data request, the data response comprising the identified data item and its associated directory information. Each of the processing elements is further configured to receive the data response and to compare the associated directory information with the access mode of the data request and in the event that the associated directory information and the access mode of the data request are not compatible, to initiate coherence actions for the requested data item. A method for cache coherency is also provided.

Attorney, Agent or Firm: Carr LLP ; Rifai, D'Ann N. ;

Primary / Asst. Examiners: Bragdon, Reginald; Gu, Shawn X.

INPADOC Legal Status: Show legal status actions          Buy Now: Family Legal Status Report

Parent Case: CROSS-REFERENCED APPLICATIONS
    This application relates to co-pending U.S. patent application entitled “A Method and Apparatus for Directory-based Coherence with Distributed Directory Management Utilizing Prefetch Caches” (U.S. patent application Ser. No. 10/809,579), filed concurrently herewith.

Family: Show 2 known family members

First Claim:
Show all 20 claims
    1. A system, comprising:

a memory comprising:

a plurality of data items and a plurality of directory information items, each data item uniquely associated with one of the plurality of directory information items;

wherein each of the plurality of data items is configured in accordance with one of a plurality of access modes;

wherein each of the plurality of directory information items comprises indicia of the access mode of its associated data item;

a multiplexer coupled to the memory and comprising a multiplex ratio;

a plurality of buffers coupled to the multiplexer and to the memory;

wherein the multiplex ratio is a function of the number of buffers in the plurality of buffers; and

a plurality of multiplexer/demultiplexers (MDMs), each MDM uniquely coupled to a different one of the plurality of buffers;

a plurality of processing elements coupled to the memory, wherein each of the processing elements uniquely couples in a point-to-point connection to a different one of the plurality of MDMs;

wherein each of the processing elements is configured to transmit a data request to its associated MDM, the data request identifying one of the plurality of data items and an access mode;

wherein the memory is configured to transmit a data response to each of the processing elements in response to a data request, the data response comprising the identified data item and its associated directory information; and

wherein each of the processing elements is further configured:

to receive the data response and to compare the associated directory information with the access mode of the data request; and

in the event that the associated directory information and the access mode of the data request are not compatible, to initiate coherence actions for the requested data item.



Background / Summary: Show background / summary

Drawing Descriptions: Show drawing descriptions

Description: Show description

       
U.S. References: Go to Result Set: All U.S. references   |  No patents reference this one   |   Backward references (10)   |   Citation Link

Buy
PDF
Patent  Pub.Date  Inventor Assignee   Title
Buy PDF- 35pp US5848254  1998-12 Hagersten  Sun Microsystems, Inc. Multiprocessing system using an access to a second memory space to initiate software controlled data prefetch into a first address space
Buy PDF- 35pp US5881303  1999-03 Hagersten et al.  Sun Microsystems, Inc. Multiprocessing system configured to perform prefetch coherency activity with separate reissue queue for each processing subnode
Buy PDF- 20pp US6374332  2002-04 Mackenthun et al.  Unisys Corporation Cache control system for performing multiple outstanding ownership requests
Buy PDF- 25pp US6587931  2003-07 Bauman et al.  Unisys Corporation Directory-based cache coherency system supporting multiple instruction processor and input/output caches
Buy PDF- 12pp US6662277  2003-12 Gaither  Hewlett-Packard Development Company, L.P. Cache system with groups of lines and with coherency for both single lines and groups of lines
Buy PDF- 19pp US6751721  2004-06 Webb et al.  Hewlett-Packard Development Company, L.P. Broadcast invalidate scheme
Buy PDF- 15pp US6934810  2005-08 Williams et al.  Unisys Corporation Delayed leaky write system and method for a cache memory
Buy PDF- 17pp US6993630  2006-01 Williams et al.  Unisys Corporation Data pre-fetch system and method for a cache memory
Buy PDF- 32pp US7089371  2006-08 Hooker  IP-First, LLC Microprocessor apparatus and method for prefetch, allocation, and initialization of a block of cache lines from memory
Buy PDF- 13pp US20030028730A1  2003-02 Gaither   Cache system with groups of lines and with coherency for both single lines and groups of lines
       
Foreign References: None

Other References:
  • David A. Patterson and John L. Hennessy, Computer Architecture A Quantitative Approach, 1996, Morgan Kaufmann Publishers, Second Edition, pp. 677-687 and 694-701.


  • Continuity Data:
    Application Number Filed Notes

    US2004000809581 2004-03-25  is a related to the prior publication
         US20050216675A1 issued 2005-09-29  Method and apparatus for directory-based coherence with distributed directory management


    Inquire Regarding Licensing

    Powered by Verity


    Plaques from Patent Awards      Gallery of Obscure PatentsNominate this for the Gallery...

    Thomson Reuters Copyright © 1997-2010 Thomson Reuters 
    Subscriptions  |  Web Seminars  |  Privacy  |  Terms & Conditions  |  Site Map  |  Contact Us  |  Help