SCGBK | Back to Index page

| Prolog Control Block Contents SCGBK DSECT Storage Layout Cross Reference (Contains links to field and bit definitions) |
Programming Interface Information: This information is NOT intended to be used as Programming Interfaces of z/VM.

SCGBK Prolog | Top of page

     NAME       : HCPSCGBK
     DESCRIPTION: 64 byte Subchannel Measurement Block
     DSECT      : SCGBK
     FUNCTION   : The measurement block is an architectually defined
                  64 byte area that contains the accumulated values
                  of the measured parameters for each subchannel.
     LOCATED BY : RDEVMBLK field of RDEVBK - logical address of
                  measurement block
     CREATED BY : HCPCHMGS when subchannel measuring is turned on for a device
     DELETED BY : HCPCHMRS when subchannel measuring is turned off for a device
     COMPATIBILITY AND MIGRATION CONCERNS : HCPSCGBK describes the 64 byte subchannel measurement block.
                  HCPSCMBK describes the 32 byte subchannel measurement block.
                  When changing this control block, check if HCPSCMBK also
                  requires changes.
     RELOCATION CONSIDERATIONS : None
     NOTES      : ABNORMAL coded because the block is updated by
                  hardware asynchronously.  The PL/X compiler may not
                  make any assumptions during optimization about the
                  data contained in this block.

SCGBK Control Block Content | Top of page

     SCGBK DSECT
    Top of page

    Hex   Dec Type/Val   Lng Label (dup)    Comments
    ---- ---- --------- ---- -------------- --------
    0000    0 Structure      SCGBK          64 byte Subchannel Measurement Block
    0000    0 Signed       4 SCGSSCH        Cyclic Count of SSCH and RSCH
    0004    4 Signed       4 SCGCOUNT       Sample Count
    0008    8 Signed       4 SCGCNTIM       Device-Connect Time
    000C   12 Signed       4 SCGFPTIM       Function-Pending Time
    0010   16 Signed       4 SCGDDTIM       Device-Disconnect Time
    0014   20 Signed       4 SCGCQTIM       Control-Unit-Queuing Time
    0018   24 Signed       4 SCGDATIM       Device-Active-Only Time
    001C   28 Signed       4 SCGDBTIM       Device-Busy Time
    0020   32 Signed       4 SCGIRTIM       Initial-Command-Response Time
    0024   36 Signed       4 SCGIDTIM       Interrupt-Delay-Time
    0028   40 Signed       4 SCGPDTIM       I/O-Priority-Delay-Time
    002C   44 Signed       4 * (5)          Reserved for future h/w use
              00000040       SCGSIZEB       (*-SCGBK) Length of SCGBK in
                                            bytes
              00000008       SCGSIZE        (*-SCGBK+7)/8 Length of SCGBK in
                                            double words

SCGBK Storage Layout | Top of page

    *** SCGBK - 64 byte Subchannel Measurement Block
    *
    *     +---------------------------+---------------------------+
    *   0 |         SCGSSCH           |         SCGCOUNT          |
    *     +---------------------------+---------------------------+
    *   8 |         SCGCNTIM          |         SCGFPTIM          |
    *     +---------------------------+---------------------------+
    *  10 |         SCGDDTIM          |         SCGCQTIM          |
    *     +---------------------------+---------------------------+
    *  18 |         SCGDATIM          |         SCGDBTIM          |
    *     +---------------------------+---------------------------+
    *  20 |         SCGIRTIM          |         SCGIDTIM          |
    *     +---------------------------+---------------------------+
    *  28 |         SCGPDTIM          |///////////////////////////|
    *     +---------------------------+///////////////////////////|
    *     |///////////////////////////////////////////////////////|
    *     |///////////////////////////////////////////////////////|
    *     +-------------------------------------------------------+
    *  40
    *
    *** SCGBK - 64 byte Subchannel Measurement Block

SCGBK Cross Reference | Top of page

    Symbol         Dspl Value
    -------------- ---- -----
    SCGCNTIM       0008
    SCGCOUNT       0004
    SCGCQTIM       0014
    SCGDATIM       0018
    SCGDBTIM       001C
    SCGDDTIM       0010
    SCGFPTIM       000C
    SCGIDTIM       0024
    SCGIRTIM       0020
    SCGPDTIM       0028
    SCGSIZE        002C 00000008
    SCGSIZEB       002C 00000040
    SCGSSCH        0000

This information is based on z/VM 7.2.0 Last updated on 24 Jun 2020 at 09:30:14 EDT.
Copyright IBM Corporation, 1990, 2020