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IV34981: INCREASE PRIORITY OF MPIO HEALTH CHECKS APPLIES TO AIX 6100-06

A fix is available

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You can track all active APARs for this component.

 

APAR status

  • Closed as program error.

Error description

  • An MPIO Disk under constant high I/O load, with failed paths is
    not recovering paths for extended period of time after the path
    has recovered  (more than 5 times the hcheck interval).  MPIO
    Disks with similar physical connections and lower I/O work
    loads are recovering the paths much quicker.  iostat with the
    -D option can be used to see the avgwqsz, avgsqsz, and sqfull
    values are all greater than "0" for an extended time.
    
    This symptom can be confused with other scenarios.  AIX MPIO
    does not health check closed disks, the disk must be opened and
    the hcheck_interval greater than "0" for health checks on
    failed paths to be requested.
    

Local fix

Problem summary

  • An MPIO Disk under constant high I/O load, with failed paths is
    not recovering paths for extended period of time after the path
    has recovered  (more than 5 times the hcheck interval).  MPIO
    Disks with similar physical connections and lower I/O work
    loads are recovering the paths much quicker.  iostat with the
    -D option can be used to see the avgwqsz, avgsqsz, and sqfull
    values are all greater than "0" for an extended time.
    
    This symptom can be confused with other scenarios.  AIX MPIO
    does not health check closed disks, the disk must be opened and
    the hcheck_interval greater than "0" for health checks on
    failed paths to be requested.
    

Problem conclusion

  • Allow a portion of the disk's queue to be used to path health
    check commands, even when the disk is saturated with read
    and write I/O requests.
    

Temporary fix

Comments

APAR Information

  • APAR number

    IV34981

  • Reported component name

    AIX 610 STD EDI

  • Reported component ID

    5765G6200

  • Reported release

    610

  • Status

    CLOSED PER

  • PE

    NoPE

  • HIPER

    NoHIPER

  • Submitted date

    2013-01-15

  • Closed date

    2013-01-15

  • Last modified date

    2013-04-10

  • APAR is sysrouted FROM one or more of the following:

    IV25121

  • APAR is sysrouted TO one or more of the following:

Fix information

  • Fixed component name

    AIX 610 STD EDI

  • Fixed component ID

    5765G6200

Applicable component levels

  • R610 PSY U855514

       UP13/03/22 I 1000

PTF to Fileset Mapping

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Document Information

Modified date:
10 April 2013