DSFBK | Back to Index page

| Prolog Control Block Contents DSFBK 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.

DSFBK Control Block Content | Top of page

     DSFBK DSECT
    Top of page

    Hex   Dec Type/Val   Lng Label (dup)    Comments
    ---- ---- --------- ---- -------------- --------
    0000    0 Structure      DSFBK          Demand Scan Information Block
    0000    0 Address      4 DSFFPNT        Forward pointer to next DSFBK
    0004    4 Address      4 DSFBPNT        Backward pointer to prev DSFBK
    0008    8 Address      4 DSFUSRBK       Ptr to bank of DSUBKs
              0000000C       DSFClr         * Area to clear before use
    000C   12 Signed       4 DSFNEED        Count of frames needed this scan
    0010   16 Dbl-Word     8 DSFSTART       Timestamp of Demand Scan start
    0018   24 Address      4 DSFUSRCR       Ptr to current DSUBK; this is
                                            basically a place where one can
                                            store the current DSUBK in order
                                            to free a register for a moment.
    001C   28 Address      4 DSFUSRLF       Ptr to head of DSUBK chain
    0020   32 Address      4 DSFUSRLL       Ptr to tail of DSUBK chain
    0024   36 Signed       4 DSFDSUCT       Count of DSUBKs used in chain
    0028   40 Dbl-Word     8 DSFENDTM       Timestamp of Demand Scan End
    0030   48 Bitstring    1 DSFwhoRq       Who requested demand scan
    0031   49 Bitstring    1 DSFwhoFl       Who actually flagged demand scan
    0032   50 Bitstring    1 * (2)          Reserved for IBM use
    0038   56 Dbl-Word     8 DSFAGCST       Aging List count at start
    0040   64 Signed       4 DSFAGFLI       Aging List ct in flight at start
    0044   68 Signed       4 DSFAGRCL       Aging List ct reclaimable
    0048   72 Dbl-Word     8 DSFAGNEE       Aging List need at start
    0050   80 Signed       4 DSFASA2G       copy of RSAIAS
    0054   84 Signed       4 DSFASB2G       copy of RSAASB2G
    0058   88 Signed       4 DSFAGDFC       copy of RSAAGDFC (deficit)
    005C   92 Signed       4 DSFRATEC       Rate-based contig need
    0060   96 Signed       4 DSFRATES       Rate-based singles need
    0064  100 Signed       4 DSF$END (0)    End of DSFBK DSECT
              00000058       DSFClrLn       *-DSFClr Length to clear
          End of DSFBK
              00000064       DSFLEN         *-DSFBK Size of DSFBK in bytes
              0000000D       DSFSIZE        (DSFLEN+7)/8 Size of DSFBK in
                                            doublewords

DSFBK Storage Layout | Top of page

    *** DSFBK - Demand Scan Information Block
    *
    *     +---------------------------+---------------------------+
    *   0 |         DSFFPNT           |         DSFBPNT           |
    *     +---------------------------+---------------------------+
    *   8 |         DSFUSRBK          |         DSFNEED           |
    *     +---------------------------+---------------------------+
    *  10 |                       DSFSTART                        |
    *     +---------------------------+---------------------------+
    *  18 |         DSFUSRCR          |         DSFUSRLF          |
    *     +---------------------------+---------------------------+
    *  20 |         DSFUSRLL          |         DSFDSUCT          |
    *     +---------------------------+---------------------------+
    *  28 |                       DSFENDTM                        |
    *     +------+------+-------------+---------------------------+
    *  30 |:WHORQ|:WHOFL|/////////////|///////////////////////////|
    *     +------+------+-------------+---------------------------+
    *  38 |                       DSFAGCST                        |
    *     +---------------------------+---------------------------+
    *  40 |         DSFAGFLI          |         DSFAGRCL          |
    *     +---------------------------+---------------------------+
    *  48 |                       DSFAGNEE                        |
    *     +---------------------------+---------------------------+
    *  50 |         DSFASA2G          |         DSFASB2G          |
    *     +---------------------------+---------------------------+
    *  58 |         DSFAGDFC          |         DSFRATEC          |
    *     +---------------------------+---------------------------+
    *  60 |         DSFRATES          |
    *     +---------------------------+
    *
    *** DSFBK - Demand Scan Information Block

DSFBK Cross Reference | Top of page

    Symbol         Dspl Value
    -------------- ---- -----
    DSF$END        0064
    DSFwhoFl       0031
    DSFwhoRq       0030
    DSFAGCST       0038
    DSFAGDFC       0058
    DSFAGFLI       0040
    DSFAGNEE       0048
    DSFAGRCL       0044
    DSFASA2G       0050
    DSFASB2G       0054
    DSFBPNT        0004
    DSFClr         0008 0000000C
    DSFClrLn       0064 00000058
    DSFDSUCT       0024
    DSFENDTM       0028
    DSFFPNT        0000
    DSFLEN         0064 00000064
    DSFNEED        000C
    DSFRATEC       005C
    DSFRATES       0060
    DSFSIZE        0064 0000000D
    DSFSTART       0010
    DSFUSRBK       0008
    DSFUSRCR       0018
    DSFUSRLF       001C
    DSFUSRLL       0020

This information is based on z/VM 7.2.0 Last updated on 24 Jun 2020 at 09:27:52 EDT.
Copyright IBM Corporation, 1990, 2020