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 - Expanded Storage Data (Global)
     DESCRIPTION - Assess use and benefits derived from expanded
                   storage. This information should be used with
                   record MRSYTXSP (Domain 0, Record 5) for a complete
                   picture of expanded storage use.

    MRSYTXSG Control Block Contents

    Offsets
    Dec Hex  Type       Len  Name (Dim)             Description

      0   0  Structure  200  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               record length in bytes
      2   2  Unsigned     2  MRHDRZER               field of zeros
      4   4  Unsigned     1  MRHDRDM                domain identifier
      5   5  Unsigned     1  *
      6   6  Unsigned     2  MRHDRRC                record identifier
      8   8  Character    8  MRHDRTOD               Time at which this record was
                                                    built. In time-of-day (TOD)
                                                    clock format. See IBM System
                                                    370 XA Principle of Operation
                                                    for explanation of format.
     16  10  Character    4  *
     20  14  Character    0  MRHDR_END              End of header
     20  14  Unsigned     4  SYTXSG_XSTXBGET        Number of expanded storage
                                                    (XSTORE) allocations. NOTE: see
                                                    record MRSTOXSU (Domain 3,
                                                    Record 10) to locate the
                                                    current user of XSTORE. If no
                                                    MRSTOXSU is written, no user is
                                                    currently attaching XSTORE.
     24  18  Unsigned     4  SYTXSG_XSTXBREL        Number of expanded storage
                                                    de-allocations
     28  1C  Unsigned     4  SYTXSG_XSTUSRSH        Number of times a Shared
                                                    System (NSS/DCSS) was visited
                                                    by migration. (Because of
                                                    multiple visits to the same
                                                    shared system, this number can
                                                    be greater than the actual
                                                    number of shares systems)
     32  20  Bitstring    8  SYTXSG_XSTCTXAV        Number of expanded storage
                                                    blocks that are available, but
                                                    not in use, by CP at this time
     40  28  Bitstring    8  SYTXSG_XSTCPPAR        Number of XSTORE blocks in CP
                                                    partition. Updated only when
                                                    XSTORE is attached or detached
                                                    from user
     48  30  Unsigned     4  SYTXSG_HCPMDCPY        Cumulative number of times
                                                    the data buffer was page
                                                    aligned for minidisk cache
                                                    usage. Value is sum of TCMPIN4K
                                                    + TCMPOU4K
     52  34  Unsigned     4  SYTXSG_HCPMDCPN        Cumulative number of times
                                                    the data buffer was not page
                                                    aligned. Value is from field
                                                    TCMPINVA. Note: when added with
                                                    SYTXSG_HCPMDCPY, the result is
                                                    the total number of data
                                                    buffers moved to and from
                                                    XSTORE.
     56  38  Unsigned     4  SYTXSG_HCPMDCPR        Cumulative number of pageins
                                                    (from XSTORE to main storage).
                                                    Value is sum of TCMPIN4K +
                                                    TCMPINVA.
     60  3C  Unsigned     4  SYTXSG_HCPMDCPW        Cumulative number of pageouts
                                                    (from main storage to XSTORE)
                                                    Value is from field TCMPOU4K.
     64  40  Unsigned     4  SYTXSG_HCPMDCAC        Maximum number of pages the
                                                    cache can be authorized to have
                                                    in expanded storage. Value is
                                                    from TCMXSMAX.
     68  44  Unsigned     4  SYTXSG_HCPMDCNE        Cardinal count of expanded
                                                    storage pages in the minidisk
                                                    cache. Values is from field
                                                    TCMXSTOR.
     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  SYTXSG_HCPMDCXG        Cumulative count of XSTORE
                                                    blocks that Minidisk Cache gets
                                                    from CP expanded storage. Value
                                                    is sum of fields TCMXSTOR +
                                                    TCMXSTDL
    132  84  Unsigned     4  SYTXSG_HCPMDCXR        Cumulative count of XSTORE
                                                    blocks that Minidisk Cache
                                                    steals from expanded storage.
                                                    Value is from field TCMXSTDL
    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  SYTXSG_TCMXIDSZ        Maximum allowable number of
                                                    XSTORE blocks in track cache
                                                    (based on avg age of XSTORE
                                                    block). AKA "ideal xstore cache
                                                    size", set by arbiter logic in
                                                    HCPSTP.
    160  A0  Unsigned     4  SYTXSG_TCMXSMIN        Minimum number of XSTORE
                                                    blocks used by cache as set by
                                                    user command
    164  A4  Unsigned     4  SYTXSG_TCMSTLXS        Number of times the steal
                                                    function was invoked to steal
                                                    XSTORE blocks from the track
                                                    cache.
    168  A8  Unsigned     4  SYTXSG_XSTAVGAG        Average age of paging XSTORE
                                                    blocks.
    172  AC  Unsigned     2  SYTXSG_HCPSTPXB        Bias for minidisk cache use
                                                    of expanded storage. A decimal
                                                    point is assumed to the left of
                                                    the low order 2 digits. For
                                                    example, a value of decimal 95
                                                    in this field would be a bias
                                                    setting of .95 .
    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  SYTXSG_TCMPIN4K        Cumulative number of 4K
                                                    aligned pageins (from XSTORE to
                                                    main storage).
    188  BC  Unsigned     4  SYTXSG_TCMPINVA        Count of page faults resolved
                                                    with PGIN to validate page for
                                                    standard track (no-4K case)
    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  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    200
    SYTXSG_CALMDCAU           54      4
    SYTXSG_END                C8      0
    SYTXSG_HCPMDCAC           40      4
    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_HCPMDCNE           44      4
    SYTXSG_HCPMDCPN           34      4
    SYTXSG_HCPMDCPR           38      4
    SYTXSG_HCPMDCPW           3C      4
    SYTXSG_HCPMDCPY           30      4
    SYTXSG_HCPMDCQC           7C      4
    SYTXSG_HCPMDCTR           88      4
    SYTXSG_HCPMDCXG           80      4
    SYTXSG_HCPMDCXR           84      4
    SYTXSG_HCPSTPXB           AC      2
    SYTXSG_MRHDR               0      0
    SYTXSG_TCMFSHVM           B0      4
    SYTXSG_TCMPINVA           BC      4
    SYTXSG_TCMPIN4K           B8      4
    SYTXSG_TCMRDCT            B4      4
    SYTXSG_TCMSTKEX           C0      4
    SYTXSG_TCMSTKPF           C4      4
    SYTXSG_TCMSTLXS           A4      4
    SYTXSG_TCMXIDSZ           9C      4
    SYTXSG_TCMXSMIN           A0      4
    SYTXSG_XSTAVGAG           A8      4
    SYTXSG_XSTCPPAR           28      8
    SYTXSG_XSTCTXAV           20      8
    SYTXSG_XSTUSRSH           1C      4
    SYTXSG_XSTXBGET           14      4
    SYTXSG_XSTXBREL           18      4

    This information is
    based on z/VM V6R1.0.

    Last updated on 8 Oct 2009 at 21:08:13.

    Copyright IBM Corporation, 1990, 2009