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VM66265: Z/VM SUPPORT FOR 80 LOGICAL PROCESSORS

A fix is available

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APAR status

  • Closed as new function.

Error description

  • Support required in z/VM 7.1.0 to allow customers to define up
    to 80 logical processors to their VM Logical Partitions.
    

Local fix

  • N/A
    

Problem summary

  • ****************************************************************
    * USERS AFFECTED: All installations running z/VM on an IBM z14 *
    *                 D/T3906                                      *
    ****************************************************************
    * PROBLEM DESCRIPTION: This PTF relieves the limitation of 64  *
    *                      logical processors per LPAR by          *
    *                      increasing that limitation to 80        *
    *                      logical processors on z14 hardware and  *
    *                      above. The new limitation allows for 40 *
    *                      cores (up to 2 threads per core) when   *
    *                      Simultaneous Multithreading (SMT) is    *
    *                      enabled, and 80 cores when SMT is       *
    *                      disabled.                               *
    ****************************************************************
    * RECOMMENDATION: APPLY PTF                                    *
    ****************************************************************
    This APAR provides the host functional support for 80 logical
    processors in a z/VM partition running on z14 (D/T3906) or
    higher. The increased support limit allows customers to run more
    workload on z/VM by increasing the number of supported logical
    processors, which is especially important when multithreading is
    enabled. This allows customers the option of defining more
    logical processors for running additional workload or
    consolidating current workloads onto a fewer number of
    LPARS.
    
    Performance evaluation for this APAR ensure that this
    support will scale according to the "capability adjustment
    factor" (CAF) coefficients up to 80 logical processors (80 cores
    in a partition if multithreading is disabled or 40 cores if
    multithreading is enabled). These coefficients express the MP
    scaling curve for a given processor family, in this case the IBM
    z14.
    
    Details of the performance scaling with the increase in
    supported capacity can be found at:
    
    http://www.vm.ibm.com/perf/reports/zvm/html/2q9r2.html/
    
    Note: z/VM host support for more than 64 logical processors does
    not add support for more than 64 virtual processors. The limit
    for the number of virtual processors defined to a VM guest
    remains at 64.
    
    Performance Toolkit support for 80 logical processors requires
    APAR VM66292
    
    Standalone Dump support for 80 logical processors requires
    APAR VM66296
    
    To support this APAR, new editions of the following publications
    are available:
    
    SC24-6268-03, z/VM: CP Commands and Utilities Reference
    GC24-6270-02, z/VM: CP Messagesand Codes
    SC24-6271-02, z/VM: CP Planning and Administration
    SC24-6272-02, z/VM: CP Programming Services
    GC24-6280-01, z/VM: Diagnose Guide
    GC24-6286-03, z/VM: General Information
    GC24-6294-03, z/VM: Migration Guide
    SC24-6301-03, z/VM: Performance
    
    For more information about the publication changes, refer to the
    Summary of Changes section located near the beginning of each
    publication.
    
    See http://www.vm.ibm.com/library/ for the online version of the
    updated publications.
    

Problem conclusion

Temporary fix

Comments

  • ×**** PE20/06/19 FIX IN ERROR. SEE APAR VM66405  FOR DESCRIPTION
    

APAR Information

  • APAR number

    VM66265

  • Reported component name

    VM CP

  • Reported component ID

    568411202

  • Reported release

    710

  • Status

    CLOSED UR1

  • PE

    NoPE

  • HIPER

    NoHIPER

  • Special Attention

    YesSpecatt / New Function / Xsystem

  • Submitted date

    2019-03-12

  • Closed date

    2019-07-30

  • Last modified date

    2020-08-25

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

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

    UM35474

Modules/Macros

  • CORE     HCPABN   HCPABW   HCPALF   HCPALG   HCPALR   HCPALU
    HCPAPI   HCPCBI   HCPCVP   HCPDFIR  HCPDMO   HCPDMP   HCPDMQ
    HCPDSB   HCPDSI   HCPDSIBK HCPDSP   HCPDSV   HCPEQUAT HCPFLGPL
    HCPHDS   HCPHIC   HCPHIP   HCPHPH   HCPHRP   HCPISM   HCPISR
    HCPIST   HCPISV   HCPMCH   HCPMCM   HCPMNP   HCPMNU   HCPMNY
    HCPMOL   HCPMOM   HCPMOT   HCPMPC   HCPMPG   HCPMTC   HCPMTF
    HCPMTO   HCPMXL   HCPPFR   HCPPGC   HCPPTF   HCPPTG   HCPQDO
    HCPQPR   HCPQPT   HCPRCC   HCPRCCBK HCPRFI   HCPRSM   HCPRSMBK
    HCPRUN   HCPSAS   HCPSCJ   HCPSGP   HCPSGQ   HCPSNP   HCPSNQ
    HCPSNR   HCPSRM   HCPSRN   HCPSTDBK HCPSTI   HCPSTK   HCPSTL
    HCPSVF   HCPSXA   HCPSXL   HCPSXP   HCPSXV   HCPSYN   HCPSZK
    HCPSZL   HCPTTA   HCPTTABK HCPVEX   HCPVMDBK HCPVNS   HCPWAI
    HCPWHI   HCPWRK   HCPWRP   HCP039E  HCQADJLD HCQBMP   HCQBUF
    HCQEQUS  HCQEXT   HCQINI   HCQSCN   HCQTIN   HCQTRC   HCQTR710
    HCQTSR   HCWAI8   HCWA12   MRPRCDHF MRUSEACT MRUSEATE MRUSELOF
    PROCESS  PROCESSO SRM      TRACERED
    

Publications Referenced
SC24626803GC24627002SC24627102SC24627202GC24628001
GC24628603GC24629403SC24630103  

Fix information

  • Fixed component name

    VM CP

  • Fixed component ID

    568411202

Applicable component levels

  • R710 PSY UM35474

       UP19/08/05 P 2001

Fix is available

  • Select the PTF appropriate for your component level. You will be required to sign in. Distribution on physical media is not available in all countries.

[{"Business Unit":{"code":"BU054","label":"Systems w/TPS"},"Product":{"code":"SG27M"},"Platform":[{"code":"PF054","label":"z Systems"}],"Version":"710"}]

Document Information

Modified date:
26 August 2020