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Prolog 
Control Block Contents 
   Threshold 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.

 
  THRESHOL Control Block Content Top of page
  




 Threshold DSECT
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Hex   Dec Type/Val   Lng Label (dup)    Comments
---- ---- --------- ---- -------------- --------
0000    0 Structure      Threshold      RSM common area mapping
0000    0 Signed       4 ThreshPT       Protect threshold.
0004    4 Signed       4 ThreshHT       High threshold.
0008    8 Signed       4 ThreshLT       Low threshold.
000C   12 Signed       4 ThreshISG      Initial value set by ALUSR.
0010   16 Signed       4 ThreshFLWM     Fuzzy low water mark.
0014   20 Signed       4 ThreshIncZ     Times incremented, hit zero.
0018   24 Signed       4 ThreshIncCnt   Times Incremented, too close to
                                        0.
001C   28 Signed       4 ThreshDecCnt   Times Decremented.
0020   32 Signed       4 ThreshGood     Times Good.
0024   36 Bitstring    1 ThreshEfgO     Efficiency flag. Observations.
                                        Flag used for adjustment of
                                        thresholds. Serialization note:
                                        There is no serialization for
                                        this byte. OI/NI are used to turn
                                        bits on and off, MVIy is used to
                                        reset the byte. A progressive
                                        system is used such that a missed
                                        update will not matter.
          1... ....      PTTransA       X'80' Set when at/above PT
                                        observed.
          .1.. ....      PTTransD       X'40' Set when below PT observed.
          ..1. ....      HTTransA       X'20' Set when at/above HT
                                        observed.
          ...1 ....      LTTransA       X'10' Set when at/above LT
                                        observed.
          .... 1...      LTTransD       X'08' Set when below LT observed.
0025   37 Bitstring    1 ThreshEFgS     Efficiency flag. Seen Flag used
                                        for adjustment of thresholds.
                                        Serialization note: There is no
                                        serialization for this byte.
                                        OI/NI are used to turn bits on
                                        and off, MVIy is used to reset
                                        the byte. A progressive system is
                                        used such that a missed update
                                        will not matter.
          ...1 ....      PTSeenA        X'10' HCPALU:CheckLT has seen
                                        PTTransA
          .... 1...      PTSeenD        X'08' HCPALU:CheckLT has seen
                                        PTTransD
          .... .1..      HTSeenA        X'04' HCPALU:CheckLT has seen
                                        HTTransA
          .... ..1.      LTSeenD        X'02' HCPALU:CheckLT has seen
                                        LTTransD
          .... ...1      RepESeen       X'01' HCPALU:CheckLT has seen rep
                                        end.
0026   38 Bitstring    1 ThreshAFg      Action flag.
          1... ....      ThreshPTRaised X'80' ThreshPTRaised The PT has
                                        been raised recentl
          .1.. ....      ThreshHTRaised X'40' ThreshHTRaised The HT has
                                        been raised recentl
          ..1. ....      ThreshLTRaised X'20' ThreshLTRaised The LT has
                                        been raised recentl
          .... 1...      ThreshPTLowered
                                        X'08' ThreshPTLowered The PT has
                                        been raised recent
          .... .1..      ThreshHTLowered
                                        X'04' ThreshHTLowered The HT has
                                        been raised recent
          .... ..1.      ThreshLTLowered
                                        X'02' ThreshLTLowered The LT has
                                        been raised recent
0027   39 Bitstring    1 *              Reserved
0028   40 Signed       4 ThreshStamp    For RSATACThresh the following 2
                                        values are for AvlTACPT For
                                        RSAT2TThresh the following 2
                                        values are for AvlT2SPT
002C   44 Signed       4 ThreshTargetB2G
                                        Local value for <2G zones.
0030   48 Signed       4 ThreshTargetA2G
                                        Local value for >2G zones.
0034   52 Signed       4 ThreshTargetLT System target value.
     | Define a local DSECT that maps the first 3 fields of     |
     | the many system execution space queues.
 
 
  THRESHOL Storage Layout Top of page
  
          
*** Threshold - RSM common area mapping
*
*     +---------------------------+---------------------------+
*   0 |         THRESHPT          |         THRESHHT          |
*     +---------------------------+---------------------------+
*   8 |         THRESHLT          |        THRESHISG          |
*     +---------------------------+---------------------------+
*  10 |        THRESHFLWM         |        THRESHINCZ         |
*     +---------------------------+---------------------------+
*  18 |       THRESHINCCNT        |       THRESHDECCNT        |
*     +---------------------------+------+------+------+------+
*  20 |        THRESHGOOD         |(024) |(025) |(026) |//////|
*     +---------------------------+------+------+------+------+
*  28 |       THRESHSTAMP         |     THRESHTARGETB2G       |
*     +---------------------------+---------------------------+
*  30 |     THRESHTARGETA2G       |      THRESHTARGETLT       |
*     +---------------------------+---------------------------+
*  38
*
*** Threshold - RSM common area mapping
 
 
  THRESHOL Cross Reference Top of page
  
 
Symbol         Dspl Value
-------------- ---- -----
HTSeenA        0025 04
HTTransA       0024 20
LTSeenD        0025 02
LTTransA       0024 10
LTTransD       0024 08
PTSeenA        0025 10
PTSeenD        0025 08
PTTransA       0024 80
PTTransD       0024 40
RepESeen       0025 01
ThreshAFg      0026
ThreshDecCnt   001C
ThreshEfgO     0024
ThreshEFgS     0025
ThreshFLWM     0010
ThreshGood     0020
ThreshHT       0004
ThreshHTLowered
               0026 04
ThreshHTRaised
               0026 40
ThreshIncCnt   0018
ThreshIncZ     0014
ThreshISG      000C
ThreshLT       0008
ThreshLTLowered
               0026 02
ThreshLTRaised
               0026 20
ThreshPT       0000
ThreshPTLowered
               0026 08
ThreshPTRaised
               0026 80
ThreshStamp    0028
ThreshTargetA2G
               0030
ThreshTargetB2G
               002C
ThreshTargetLT
               0034
 
This information is based on z/VM 7.3.0 Last updated on 22 Jun 2022 at 15:54:37 EDT.
Copyright IBM Corporation, 1990, 2022