IBM Support

VM65918: NEW FUNCTION : VSWITCH LINK AGGREGATION ENHANCEMENTS

A fix is available

Subscribe

You can track all active APARs for this component.

APAR status

  • Closed as new function.

Error description

  • Improve load balancing and packet transmission serialization.
    

Local fix

Problem summary

  • ****************************************************************
    * USERS AFFECTED: All users of VSwitch networks                *
    ****************************************************************
    * PROBLEM DESCRIPTION:                                         *
    ****************************************************************
    * RECOMMENDATION: APPLY PTF                                    *
    ****************************************************************
    With the PTF for APAR VM65918, z/VM support for exclusive and
    Multi-VSwitch Link Aggregation configurations is enhanced to
    improve load balancing to leverage both horizontal and vertical
    growth in single and cross virtual switch
    networking configurations.
    

Problem conclusion

Temporary fix

Comments

  • Load Balance Enhancements
    
    Two new port group management options are now available
    to balance the work load for a link aggregated port group
    (LAG) configured to a z/VM VSwitch. For a Multi-VSwitch LAG
    configuration, a system administrator has the option to use
    either existing Independent Port Group Management
    or a new type called Collaborative Port Group Management.
    
    Independent Port Group Management allows each VSwitch sharing
    the same port group to independently manage their own work load
    across all the OSA-Express features within the port group.
    Prior to this new support, this is the method used for either
    an exclusive or a shared port group. With this APAR, a
    Multi-VSwitch LAG can use a new type of load balance called
    Collaborative Load Balance Management.
    
    With Collaborative Port Group Management, only a single VSwitch
    sharing the same port group will be tasked with balancing
    the work load across all the OSA-Express features.
    The coordination and management of the shared port group
    is handled by new communications via the IVL Network.
    This method of management now takes into consideration
    the overall usage of the port group rather than the view of a
    single VSwitch when balancing the work load.
    
    With either independent or collaborative management,
    load balance efficiency is increased for port groups containing
    greater than three OSA-Express features.
    Prior to this APAR, a load balance interval only considered
    moving work load from a single pair of ports. Basically,
    moving work load from the most to the least utilized
    OSA-Express feature. With this APAR z/VM will no longer stop
    attempting to move work load on additional ports within
    the group, assuming they would be handled by the next load
    balance interval. After moving work load on the first pair
    of devices, the new logic will then select the next most
    and least utilized ports and perform the load balance
    operation. This is then repeated for all the remaining
    OSA-Express features in the port group.
    
    VSwitch Packet Transmission Enhancement
    
    Main line data transmission serialization changes have been
    made to the VSwitch logic when sending and receiving
    a packet from one port to another. This includes
    communications between a simulated port to another simulated
    port or more importantly between a simulated and a real
    port (UpLink or Bridge Port). Prior serialization only
    permitted a data transmission to occur from a given port in one
    direction at any point in time. The new serialization provided
    by this APAR will now allow data to flow concurrently
    in both directions when there are enough processors available.
    
    Refer to z/VM Connectivity Version 6 Release 4 (SC24-6174-09)
    for more information.
    
    The following additional publications have been updated for this
    support:
        GC24-6193-16: General Information
        SC24-6175-12: CP Commands and Utilities Reference
        SC24-6178-13: CP Planning and Administration
        SC24-6179-12: CP Programming Services
        GC24-6177-11: CP Messages and Codes
        SC24-6208-10: Performance
        GC24-6201-13: Migration
    

APAR Information

  • APAR number

    VM65918

  • Reported component name

    VM CP

  • Reported component ID

    568411202

  • Reported release

    640

  • Status

    CLOSED UR1

  • PE

    NoPE

  • HIPER

    NoHIPER

  • Special Attention

    YesSpecatt / New Function / Xsystem

  • Submitted date

    2016-10-13

  • Closed date

    2017-12-04

  • Last modified date

    2018-12-14

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

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

    UM35252 UM35253

Modules/Macros

  • CPLOAD   HCPCBI   HCPCSIBK HCPCVV   HCPGPGBK HCPHVD   HCPIQD
    HCPIQE   HCPIQQ   HCPIQR   HCPIVA   HCPIVC   HCPIVD   HCPIVF
    HCPIVG   HCPIVH   HCPIVL   HCPIVLBK HCPIVS   HCPLAN   HCPLANBK
    HCPMDLAT HCPMES   HCPMESA  HCPMESB  HCPMFN   HCPMLM   HCPMLT
    HCPMNO   HCPMVN   HCPMXD   HCPMXRBK HCPNIDBK HCPRLG   HCPRLOBK
    HCPSCFBK HCPSWA   HCPSWB   HCPSWD   HCPSWK   HCPSWL   HCPSWP
    HCPSWPBK HCPSWS   HCPSWY   HCPSXL   HCPSYN   HCPUCP   HCPVLC
    HCPVLF   HCPVLQ   HCPVLS   HCPVLU   HCPVNS   HCPVQT   HCPVQU
    HCP1935E HCP3199E HCP3223E HCP3225E MRIODVSW MRVNDSES PORT
    VMLAN    VSWITCH
    

Publications Referenced
SC24617512 GC24617711 SC24617813 SC24617912 SC24620810
SC24617409 SC24620113 GC24619316    

Fix information

  • Fixed component name

    VM CP

  • Fixed component ID

    568411202

Applicable component levels

  • RA64 PSY UM34768

       UP18/12/14 P 1802  

  • R640 PSY UM35253

       UP17/12/11 P 1802  

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.



Document information

More support for: z/VM family

Software version: 640

Operating system(s): z/VM

Reference #: VM65918

Modified date: 14 December 2018