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

MRIODCAD

Prolog
Control Block Contents
Cross Reference

MRIODCAD Prolog

 DSECT NAME - IODCAD
 FUNCTION - Map a Monitor record.
 LOCATED BY -
        Through the Monitor Control Area
 REFERENCED CONTROL BLOCKS -
        MRRECHDR    Monitor Record Header
 NAME - MRIODCAD
 DESCRIPTIVE NAME - Monitor Sample Record
                    Domain 6 - I/O Domain
                    Record 4 - Cache Activity Data
 DESCRIPTION - Records cache activities.  Generated for each device
               that is attached to a caching control unit such as
               a 3880 model 11, 13, 21, and 23, or a 3990 model 3.
               Its purpose is to enable management of the paging
               cache in the storage directors.
 NOTES:
  -- Data in IODCAD_CALDATA depends on the type of device being
     monitored.  The IODCAD_STATUS code indicates what kind of data
     is in it.
  -- For the 3880 Model 11, only the storage director that
     owns the cache is recorded.
  -- This record is not created for the secondary of a PPRC
     pair.
  -- This record is not created for PAV Alias devices
  -- This record is not created for HyperPAV Alias devices


MRIODCAD Control Block Contents

Offsets
Dec Hex  Type       Len  Name (Dim)             Description
 
  0   0  Structure  264  IODCAD                 
  0   0  Character    0  IODCAD_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  IODCAD_RDEVSID         host subchannel I.D. number
                                                defined at initialization
 24  18  Signed       4  IODCAD_STATUS          code pertaining to contents
                                                and mapping of the
                                                IODCAD_CALDATA data area: -2 =
                                                No data because an I/O request
                                                to obtain cache information
                                                exceeded an internal timer
                                                value and was cancelled. -1 =
                                                No data because the device is a
                                                potential SIE ASSIST device. 0
                                                = I/O Error in producing the
                                                record. No data. 1 = data from
                                                one storage director of a 3880.
                                                Mapped by IODCAD_CALDSSC. 2 =
                                                data from both storage
                                                directors of a 3880. Mapped by
                                                IODCAD_CALDSSC. 3 = data from a
                                                3990 model 3 or 6, a Shark, a
                                                9394, or a 9696 Mapped by
                                                IODCAD_CALPSF.
 28  1C  Bitstring   40  IODCAD_CALSSS          Subsystem status, as returned
                                                by the SENSE SUBSYSTEM STATUS
                                                command. Layout and contents,
                                                which depend on the device, are
                                                described in the device's
                                                hardware manuals. If the device
                                                returns more than 40 bytes of
                                                subsystem status, field
                                                IODCAD_CALSSS2 contains the
                                                additional status
 28  1C  Character    6  *                      Defined in device hardware
                                                manuals (see above).
 34  22  Signed       2  IODCAD_PSFLEN          Length (in bytes) of
                                                performance statistics which
                                                are stored in IODCAD_CALPSF for
                                                this device. If this field is
                                                zero, then the performance
                                                statistics length is 96 bytes.
 36  24  Character   32  *                      Defined in device hardware
                                                manuals (see above).
 68  44  Character  192  IODCAD_CALDATA         Data area. Contains status
                                                and/or performance data. See
                                                code in IODCAD_STATUS. Layout
                                                and contents, which depend on
                                                the device, are described in
                                                the device's hardware manuals.
260 104  Bitstring    4  IODCAD_CALSSS2         Additional subsystem status
                                                as returned by the SENSE
                                                SUBSYSTEM STATUS command.
                                                Layout and contents, which
                                                depend on the device, are
                                                described in the device's
                                                hardware manuals.
264 108  Character    0  IODCAD_END             

IODCAD_CALDSSC Status and performance data collected from a 3880 control unit. If IODCAD_STATUS = 1 data was collected only from the first storage director. IODCAD_CALSSC2 will not apply. If IODCAD_STATUS = 2 data was collected from both storage directors.
Offsets Dec Hex Type Len Name (Dim) Description 0 0 Structure 160 IODCAD_CALDSSC 0 0 Bitstring 80 IODCAD_CALSSC1 Subsystem performance data, as returned by the SENSE SUBSYSTEM COUNTS command for the first storage director 80 50 Bitstring 80 IODCAD_CALSSC2 Subsystem performance data, as returned by the SENSE SUBSYSTEM COUNTS command for the second storage director. Applicable only when IODCAD_STATUS = 2.
IODCAD_CALPSF Status and performance data collected from a 3990 model 3 or 6 a 9394 a 9696 or a Shark. Applicable only when IODCAD_STATUS = 3.
Offsets Dec Hex Type Len Name (Dim) Description 0 0 Structure 0 * 0 0 Character 192 IODCAD_CALPSF Subsystem performance data, as returned by the PERFORM SUBSYSTEM FUNCTION, READ SUBSYSTEM DATA (PERFORMANCE STATISTICS) CCW chain

MRIODCAD Cross Reference

                      Hex           Hex
Name                 Offset Length Value
 
IODCAD                     0    264
IODCAD_CALDATA            44    192
IODCAD_CALDSSC             0    160
IODCAD_CALPSF              0    192
IODCAD_CALSSC1             0     80
IODCAD_CALSSC2            50     80
IODCAD_CALSSS             1C     40
IODCAD_CALSSS2           104      4
IODCAD_END               108      0
IODCAD_MRHDR               0      0
IODCAD_PSFLEN             22      2
IODCAD_RDEVSID            14      4
IODCAD_STATUS             18      4
MRHDR                      0     20
MRHDR_END                 14      0
MRHDRDM                    4      1
MRHDRLEN                   0      2
MRHDRRC                    6      2
MRHDRTOD                   8      8
MRHDRZER                   2      2

This information is based on z/VM V6R1.0.
Last updated on 8 Oct 2009 at 21:11:45.
Copyright IBM Corporation, 1990, 2009