CA2063897A1 - Method and means for distributed sparing in dasd arrays - Google Patents

Method and means for distributed sparing in dasd arrays

Info

Publication number
CA2063897A1
CA2063897A1 CA2063897A CA2063897A CA2063897A1 CA 2063897 A1 CA2063897 A1 CA 2063897A1 CA 2063897 A CA2063897 A CA 2063897A CA 2063897 A CA2063897 A CA 2063897A CA 2063897 A1 CA2063897 A1 CA 2063897A1
Authority
CA
Canada
Prior art keywords
parity
spare
accesses
data
blocks
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
CA2063897A
Other languages
French (fr)
Other versions
CA2063897C (en
Inventor
Jaishankar Moothedath Menon
Richard Lewis Mattson
Spencer Wah-Fung Ng
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
International Business Machines Corp
Original Assignee
International Business Machines Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by International Business Machines Corp filed Critical International Business Machines Corp
Publication of CA2063897A1 publication Critical patent/CA2063897A1/en
Application granted granted Critical
Publication of CA2063897C publication Critical patent/CA2063897C/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F11/00—Error detection; Error correction; Monitoring
    • G06F11/07—Responding to the occurrence of a fault, e.g. fault tolerance
    • G06F11/16—Error detection or correction of the data by redundancy in hardware
    • G06F11/20—Error detection or correction of the data by redundancy in hardware using active fault-masking, e.g. by switching out faulty elements or by switching in spare elements
    • G06F11/2053—Error detection or correction of the data by redundancy in hardware using active fault-masking, e.g. by switching out faulty elements or by switching in spare elements where persistent mass storage functionality or persistent mass storage control functionality is redundant
    • G06F11/2094—Redundant storage or storage space
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F11/00—Error detection; Error correction; Monitoring
    • G06F11/07—Responding to the occurrence of a fault, e.g. fault tolerance
    • G06F11/08—Error detection or correction by redundancy in data representation, e.g. by using checking codes
    • G06F11/10—Adding special bits or symbols to the coded information, e.g. parity check, casting out 9's or 11's
    • G06F11/1076—Parity data used in redundant arrays of independent storages, e.g. in RAID systems
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F11/00—Error detection; Error correction; Monitoring
    • G06F11/07—Responding to the occurrence of a fault, e.g. fault tolerance
    • G06F11/16—Error detection or correction of the data by redundancy in hardware
    • G06F11/1658—Data re-synchronization of a redundant component, or initial sync of replacement, additional or spare unit
    • G06F11/1662—Data re-synchronization of a redundant component, or initial sync of replacement, additional or spare unit the resynchronized component or unit being a persistent storage device
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11C—STATIC STORES
    • G11C29/00—Checking stores for correct operation ; Subsequent repair; Testing stores during standby or offline operation
    • G11C29/70—Masking faults in memories by using spares or by reconfiguring
    • G11C29/88—Masking faults in memories by using spares or by reconfiguring with partially good memories
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F2211/00—Indexing scheme relating to details of data-processing equipment not covered by groups G06F3/00 - G06F13/00
    • G06F2211/10—Indexing scheme relating to G06F11/10
    • G06F2211/1002—Indexing scheme relating to G06F11/1076
    • G06F2211/1028—Distributed, i.e. distributed RAID systems with parity

Landscapes

  • Engineering & Computer Science (AREA)
  • Theoretical Computer Science (AREA)
  • Quality & Reliability (AREA)
  • Physics & Mathematics (AREA)
  • General Engineering & Computer Science (AREA)
  • General Physics & Mathematics (AREA)
  • Techniques For Improving Reliability Of Storages (AREA)
  • Hardware Redundancy (AREA)
  • Information Retrieval, Db Structures And Fs Structures Therefor (AREA)

Abstract

A method and means in which data and parity blocks forming parity groups together with spare blocks are distributed over array block locations according to at least one combinatorial design, each group having N data and P parity blocks. The combinatorial designs yield uniform or balanced loading thereby minimizing the number of accesses to reconstruct missing data and parity blocks and their copyback into spare block locations, and, minimize the number of accesses to the reconstructed data referenced subsequent to its copyback. Distributions of the spare block capacity of one or two DASDs are shown over single and multiple arrays and shared among multiple arrays. Parity block distribution although ancillary to spare distribution enhances throughput and reduces the number of accesses for rebuild etc.
CA002063897A 1991-06-13 1992-03-24 Method and means for distributed sparing in dasd arrays Expired - Fee Related CA2063897C (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US07/714,969 US5258984A (en) 1991-06-13 1991-06-13 Method and means for distributed sparing in DASD arrays
US07/714,969 1991-06-13

Publications (2)

Publication Number Publication Date
CA2063897A1 true CA2063897A1 (en) 1992-12-14
CA2063897C CA2063897C (en) 1998-05-05

Family

ID=24872213

Family Applications (1)

Application Number Title Priority Date Filing Date
CA002063897A Expired - Fee Related CA2063897C (en) 1991-06-13 1992-03-24 Method and means for distributed sparing in dasd arrays

Country Status (9)

Country Link
US (1) US5258984A (en)
EP (1) EP0518603B1 (en)
JP (1) JPH0724039B2 (en)
KR (1) KR940011039B1 (en)
BR (1) BR9202160A (en)
CA (1) CA2063897C (en)
DE (1) DE69219208T2 (en)
HK (1) HK1000076A1 (en)
TW (1) TW210386B (en)

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Also Published As

Publication number Publication date
EP0518603B1 (en) 1997-04-23
BR9202160A (en) 1993-02-02
TW210386B (en) 1993-08-01
CA2063897C (en) 1998-05-05
DE69219208T2 (en) 1997-10-16
HK1000076A1 (en) 1997-11-14
US5258984A (en) 1993-11-02
DE69219208D1 (en) 1997-05-28
JPH05100960A (en) 1993-04-23
KR940011039B1 (en) 1994-11-22
JPH0724039B2 (en) 1995-03-15
EP0518603A2 (en) 1992-12-16
EP0518603A3 (en) 1993-10-06

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