Programming Interface Information: The Monitor Records are intended Programming Interfaces that allow the customer to write programs to obtain services of z/VM.

#### MRPRCDHF

Prolog
Control Block Contents
Cross Reference

#### MRPRCDHF Prolog

     DSECT NAME - PRCDHF
     FUNCTION - Map a Monitor record.
     LOCATED BY -
            Through the Monitor Control Area
     REFERENCED CONTROL BLOCKS -
            MRRECHDR    Monitor Record Header
     NAME - MRPRCDHF
     DESCRIPTIVE NAME - Monitor Sample Record
                        Domain  5 - Processor Domain
                        Record 18 - Dispatch Vector High Frequency Data
     DESCRIPTION - Provides high frequency sampling data related to
                   dispatch vectors (DSVBKs). One stanza is provided
                   for each DSVBK that is currently in use. The master
                   DSVBK is indicated by a DSVBK id (PRCDHF_CALDSVID)
                   of x'FFFF'.
                   PRCDHF_RCCDSVCH is provided as a way to know whether
                   CPU-to-DSVBK assignments have changed since the last
                   sample. If they have, this record should not be
                   compared with the previous. Events which cause
                   CPU-to_DSVBK assignments to change include:
                   - CPU topology changes
                   - VARY ON|OFF of a CPU
                   - Dedication/undedication of a virtual CPU
                   When this record is present in monitor data,
                   this record and Domain 5 Record 17 should be used
                   instead of Domain 5 Record 3. Domain 5 Records 17
                   and 18 are intended to replace Domain 5 Record 3.

#### MRPRCDHF Control Block Contents

    Offsets
    Dec  Hex  Type        Len  Name (Dim)             Description

       0   0  Structure    44+ PRCDHF                 Start of monitor record
       0   0  Character     0  PRCDHF_MRHDR           Record header. See MRRECHDR
                                                      for details.
       0   0  Character    20  MRHDR
       0   0  Unsigned      2  MRHDRLEN
       2   2  Unsigned      2  MRHDRZER
       4   4  Unsigned      1  MRHDRDM
       5   5  Unsigned      1  *
       6   6  Unsigned      2  MRHDRRC
       8   8  Character     8  MRHDRTOD
      16  10  Character     4  *
      20  14  Character     0  MRHDR_END
      20  14  Unsigned      2  PRCDHF_SCOUNT          Number of stanzas in this
                                                      record
      22  16  Unsigned      2  PRCDHF_SSIZE           Size of a stanza (bytes)
      24  18  Unsigned      2  PRCDHF_SOFFSET         Offset within this record
                                                      to the first stanza
      26  1A  Unsigned      2  PRCDHF_MAXRPROC        This value defines the
                                                      number of valid bits in bit
                                                      masks: PRCDHF_DSVASSOC,
                                                      PRCDHF_DSVUNPRK.
      28  1C  Unsigned      4  PRCDHF_RCCDSVCH        Count of times CPU-to-DSVBK
                                                      assignments have changed
      32  20  Unsigned      4  PRCDHF_SYSDVENT        Maximum number of VMDBKs
                                                      allowed in a DSVBK
      36  24  Unsigned      2  PRCDHF_OFSASSOC        PRCDHF_DSVASSOC field
                                                      offset from beginning of the
                                                      stanza.
      38  26  Unsigned      2  PRCDHF_OFSUNPRK        PRCDHF_DSVUNPRK field
                                                      offset from beginning of the
                                                      stanza.
      40  28  Unsigned      1  PRCDHF_CONT            Record continuation
                                                      identifier:
                                                      0 = The record does not
                                                          continue into an
                                                          additional record. This
                                                          is the last record.
                                                      1 = The record continues
                                                          into additional records.
      41  29  Character     3  *                      Reserved for IBM use
      44  2C  Character     0  *                      Additional fields may be
                                                      inserted before here. Use
                                                      offsets to locate any fields
                                                      after this point.
      44  2C  Character     0  PRCDHF_STANZAS         Start of first stanza. The
                                                      first stanza should be
                                                      located by adding
                                                      PRCDHF_SOFFSET to the address
                                                      of this record. Subsequent
                                                      stanzas should be located by
                                                      adding PRCDHF_SSIZE to the
                                                      address of the current
                                                      stanza.
    Mapping of the stanzas located beginning at PRCDHF_STANZAS.

    Offsets
    Dec  Hex  Type        Len  Name (Dim)             Description

       0   0  Structure    16+ PRCDHF_STANZA          Start of a stanza for a
                                                      DSVBK
       0   0  Unsigned      2  PRCDHF_CALDSVID        DSVBK id
       2   2  Unsigned      1  *                      reserved for IBM use
       3   3  Unsigned      1  PRCDHF_CPUTYPE         CPU type being described.
                                                      0=CP, 2=zAAP, 3=IFL, 4=ICF,
                                                      5=zIIP.
       4   4  Character    12  PRCDHF_HFSAMPLE
       4   4  Unsigned      4  PRCDHF_HFCOUNT         Number of times this DSVBK
                                                      was sampled for high
                                                      frequency data.
       8   8  Unsigned      4  PRCDHF_HFUSERZ         High-frequency count.
                                                      Number of times the DSVBK had
                                                      no VMDBKs
      12   C  Unsigned      4  PRCDHF_HFUSERC         High-frequency count.
                                                      Cumulative number of VMDBKs
                                                      in the DSVBK when the DSVBK
                                                      was not empty (DSVUSERC).
      16  10  Character     0  *                      Additional fields may be
                                                      inserted before here. Use
                                                      offsets to locate any fields
                                                      after this point.
       0   0  Bit           1  PRCDHF_DSVASSOC(MAXVMPRC) Bit mask of CPUs
                                                      associated with this DSVBK.
                                                      PRCDHF_MAXRPROC should be used
                                                      to determine the length (in
                                                      bits) of this field.
                                                      PRCDHF_OFSASSOC should be used
                                                      to locate this field.
       0   0  Bit           1  PRCDHF_DSVUNPRK(MAXVMPRC) Bit mask indicating
                                                      which CPUs associated with this
                                                      DSVBK are currently in the
                                                      unparked state.
                                                      PRCDHF_MAXRPROC should be used
                                                      to determine the length (in
                                                      bits) of this field.
                                                      PRCDHF_OFSUNPRK should be used
                                                      to locate this field.
       *   *  Character     0  PRCDHF_END_STANZA      End of stanza

#### MRPRCDHF Cross Reference

                          Hex           Hex
    Name                  Offset Length Value

    MRHDR                      0     20
    MRHDR_END                 14      0
    MRHDRDM                    4      1
    MRHDRLEN                   0      2
    MRHDRRC                    6      2
    MRHDRTOD                   8      8
    MRHDRZER                   2      2
    PRCDHF                     0     44+
    PRCDHF_CALDSVID            0      2
    PRCDHF_CONT               28      1
    PRCDHF_CPUTYPE             3      1
    PRCDHF_DSVASSOC            0      *
    PRCDHF_DSVUNPRK            0      *
    PRCDHF_END_STANZA          *      *
    PRCDHF_HFCOUNT             4      4
    PRCDHF_HFSAMPLE            4     12
    PRCDHF_HFUSERC             C      4
    PRCDHF_HFUSERZ             8      4
    PRCDHF_MAXRPROC           1A      2
    PRCDHF_MRHDR               0      0
    PRCDHF_OFSASSOC           24      2
    PRCDHF_OFSUNPRK           26      2
    PRCDHF_RCCDSVCH           1C      4
    PRCDHF_SCOUNT             14      2
    PRCDHF_SOFFSET            18      2
    PRCDHF_SSIZE              16      2
    PRCDHF_STANZA              0     16+
    PRCDHF_STANZAS            2C      0
    PRCDHF_SYSDVENT           20      4

    This information is
    based on z/VM V7R2.0.

    Last updated on 09 August 2020 at 14:39:15.

    Copyright IBM Corporation, 1990, 2020