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

#### MRSYTXSG

Prolog
Control Block Contents
Cross Reference

#### MRSYTXSG Prolog

     DSECT NAME - SYTXSG
     FUNCTION - Map a Monitor record.
     LOCATED BY -
            Through the Monitor Control Area
     REFERENCED CONTROL BLOCKS -
            MRRECHDR    Monitor Record Header
     NAME - MRSYTXSG
     DESCRIPTIVE NAME - Monitor Sample Record
                        Domain 0  - System Domain
                        Record 14 - Minidisk Cache Data (Global)
     DESCRIPTION - Assess use and benefits derived from minidisk
                   cache.

#### MRSYTXSG Control Block Contents

    Offsets
    Dec  Hex  Type        Len  Name (Dim)             Description

       0   0  Structure   204  SYTXSG                 Start of monitor record
       0   0  Character     0  SYTXSG_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      4  *                      Reserved for IBM use - was
                                                      SYTXSG_XSTXBGET
      24  18  Unsigned      4  *                      Reserved for IBM use - was
                                                      SYTXSG_XSTXBREL
      28  1C  Unsigned      4  *                      Reserved for IBM use - was
                                                      SYTXSG_XSTUSRSH
      32  20  Bitstring     8  *                      Reserved for IBM use - was
                                                      SYTXSG_XSTCTXAV
      40  28  Bitstring     8  *                      Reserved for IBM use - was
                                                      SYTXSG_XSTCPPAR
      48  30  Unsigned      4  *                      Reserved for IBM use - was
                                                      SYTXSG_HCPMDCPY
      52  34  Unsigned      4  *                      Reserved for IBM use - was
                                                      SYTXSG_HCPMDCPN
      56  38  Unsigned      4  *                      Reserved for IBM use - was
                                                      SYTXSG_HCPMDCPR
      60  3C  Unsigned      4  *                      Reserved for IBM use - was
                                                      SYTXSG_HCPMDCPW
      64  40  Unsigned      4  *                      Reserved for IBM use - was
                                                      SYTXSG_HCPMDCAC
      68  44  Unsigned      4  *                      Reserved for IBM use - was
                                                      SYTXSG_HCPMDCNE
      72  48  Unsigned      4  *                      Reserved for IBM use.
                                                      Previous field is no longer
                                                      meaningful. (SYTXSG_HCPMDCPH)
      76  4C  Unsigned      4  SYTXSG_HCPMDCEX        Cumulative number of times
                                                      a data buffer was not put in
                                                      the cache because the fair
                                                      share limit was exceeded.
                                                      Value is from TCMFSLEX.
      80  50  Unsigned      4  SYTXSG_HCPMDCLI        Number of data buffers the
                                                      user can insert per fair
                                                      share interval. Value is from
                                                      field TCMFSLIM.
      84  54  Unsigned      4  SYTXSG_CALMDCAU        Number of users that did at
                                                      least one insert into the
                                                      cache since the last fair
                                                      share interval. Value is from
                                                      sum of TCMFSHVM+TCMNFSVM
      88  58  Unsigned      4  *                      Reserved for IBM use.
                                                      Previous field is no longer
                                                      meaningful. (SYTXSG_HCPMDCHT)
      92  5C  Unsigned      4  *                      Reserved for IBM use.
                                                      Previous field is no longer
                                                      meaningful. (SYTXSG_HCPMDCMS)
      96  60  Unsigned      4  *                      Reserved for IBM use.
                                                      Previous field is no longer
                                                      meaningful. (SYTXSG_HCPMDCEM)
     100  64  Unsigned      4  SYTXSG_HCPMDCIS        Cumulative number of
                                                      inserts into the hash table.
                                                      Value is from field TCMINSCT.
     104  68  Unsigned      4  *                      Reserved for IBM use.
                                                      Previous field is no longer
                                                      meaningful. (SYTXSG_HCPMDCSP)
     108  6C  Unsigned      4  *                      Reserved for IBM use.
                                                      Previous field is no longer
                                                      meaningful. (SYTXSG_HCPMDCSU)
     112  70  Unsigned      4  *                      Reserved for IBM use.
                                                      Previous field is no longer
                                                      meaningful. (SYTXSG_HCPMDCFP)
     116  74  Unsigned      4  *                      Reserved for IBM use.
                                                      Previous field is no longer
                                                      meaningful. (SYTXSG_HCPMDCFA)
     120  78  Unsigned      4  *                      Reserved for IBM use.
                                                      Previous field is no longer
                                                      meaningful. (SYTXSG_HCPMDCLP)
     124  7C  Unsigned      4  SYTXSG_HCPMDCQC        Cumulative number of
                                                      insertions into the waiting
                                                      queue. The waiting queue
                                                      keeps track of users that are
                                                      trying to request data that
                                                      is already on its way to the
                                                      cache. Value is sum of fields
                                                      TCMSTKRD, TCMSTKEX, and
                                                      TCMSTKPF.
     128  80  Unsigned      4  *                      Reserved for IBM use - was
                                                      SYTXSG_HCPMDCXG
     132  84  Unsigned      4  *                      Reserved for IBM use - was
                                                      SYTXSG_HCPMDCXR
     136  88  Unsigned      4  SYTXSG_HCPMDCTR        Total eligible minidisk
                                                      cache read requests:
                                                      Cumulative number of requests
                                                      to read one or more blocks of
                                                      data from cache. Value is
                                                      from TCMIA + TCMINOTA.
     140  8C  Unsigned      4  SYTXSG_HCPMDCIA        I/Os avoided: Cumulative
                                                      number of requests to read
                                                      data from cache where all
                                                      requested blocks were found
                                                      in cache, thereby avoiding an
                                                      I/O operation. Value is from
                                                      field TCMIA.
     144  90  Unsigned      4  SYTXSG_HCPMDCIB        Invalidated blocks:
                                                      Cumulative number of cache
                                                      blocks invalidated (discarded
                                                      from cache) due to I/O issued
                                                      at the virtual device level
                                                      via a non-cachable I/O
                                                      interface. Value is from
                                                      field TCMDELCT.
     148  94  Unsigned      4  SYTXSG_HCPMDCIT        Invalidation total
                                                      requests: Cumulative number
                                                      of requests to invalidate
                                                      cache due to I/O issued to a
                                                      virtual device via a
                                                      non-cachable I/O interface.
                                                      This includes requests where
                                                      there were no blocks in cache
                                                      for that virtual device, and
                                                      therefore no blocks
                                                      invalidated. One request may
                                                      result in zero to several
                                                      blocks being discarded from
                                                      the cache. Value is sum of
                                                      fields
                                                      TCMDCCT+TCMUDFST+TCMUDMLT
     152  98  Unsigned      4  *                      Reserved for IBM use.
                                                      Previous field is no longer
                                                      meaningful. (SYTXSG_HCPMDCIH)
     156  9C  Unsigned      4  *                      Reserved for IBM use - was
                                                      SYTXSG_TCMXIDSZ
     160  A0  Unsigned      4  *                      Reserved for IBM use - was
                                                      SYTXSG_TCMXSMIN
     164  A4  Unsigned      4  *                      Reserved for IBM use - was
                                                      SYTXSG_TCMSTLXS
     168  A8  Unsigned      4  *                      Reserved for IBM use - was
                                                      SYTXSG_XSTAVGAG
     172  AC  Unsigned      2  *                      Reserved for IBM use - was
                                                      SYTXSG_HCPSTPXB
     174  AE  Character     2  *                      Reserved and available for
                                                      IBM use.
     176  B0  Unsigned      4  SYTXSG_TCMFSHVM        Number of fair share cache
                                                      inserters during this fair
                                                      share interval.
     180  B4  Unsigned      4  SYTXSG_TCMRDCT         Count of successful read
                                                      access to MDC records.
     184  B8  Unsigned      4  *                      Reserved for IBM use - was
                                                      SYTXSG_TCMPIN4K
     188  BC  Unsigned      4  *                      Reserved for IBM use - was
                                                      SYTXSG_TCMPINVA
     192  C0  Unsigned      4  SYTXSG_TCMSTKEX        Count of times a CPEBK was
                                                      deferred on a track (writes)
     196  C4  Unsigned      4  SYTXSG_TCMSTKPF        Count of times a CPEBK was
                                                      deferred on a track (page
                                                      fault priority)
     200  C8  Unsigned      4  SYTXSG_TCMCPURG        Cumulative count of times
                                                      cache purged due to a write
                                                      link obtained in the SSI.
     204  CC  Character     0  SYTXSG_END

#### MRSYTXSG 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
    SYTXSG                     0    204
    SYTXSG_CALMDCAU           54      4
    SYTXSG_END                CC      0
    SYTXSG_HCPMDCEX           4C      4
    SYTXSG_HCPMDCIA           8C      4
    SYTXSG_HCPMDCIB           90      4
    SYTXSG_HCPMDCIS           64      4
    SYTXSG_HCPMDCIT           94      4
    SYTXSG_HCPMDCLI           50      4
    SYTXSG_HCPMDCQC           7C      4
    SYTXSG_HCPMDCTR           88      4
    SYTXSG_MRHDR               0      0
    SYTXSG_TCMCPURG           C8      4
    SYTXSG_TCMFSHVM           B0      4
    SYTXSG_TCMRDCT            B4      4
    SYTXSG_TCMSTKEX           C0      4
    SYTXSG_TCMSTKPF           C4      4

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

    Last updated on 08 August 2020 at 16:03:11.

    Copyright IBM Corporation, 1990, 2020