SRXBK Back to Index page
 
Prolog 
Control Block Contents 
   SRXBK 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.


  SRXBK Prolog Top of page
 
 NAME       : HCPSRXBK
 DESCRIPTION: System Resource Management block extensions
 DSECT      : SRXBK
 FUNCTION   : HCPSRXBK contains original SRMBK fields which are
              duplicated for Mixed-Engine partitions.  These
              fields are used by the System Resource Manager
              (Scheduler) in the maintainance of user lists and
              calculation of various scheduling parameters.
 LOCATED BY : SRMXTBL table of SRXBK pointers by processor
              type
 CREATED BY : HCPIST during system initialization
 DELETED BY : Never deleted
 REFERENCES : None
 SERIALIZED : Scheduler lock (SRMSLOCK)
 RELOCATION CONSIDERATIONS : None
 COMPATIBILITY AND MIGRATION CONCERNS : An SRXBK exists for
              each processor type that is valid in a Mixed-Engines
              configuration.  Prior to Mixed-Engines support, these
              fields were global scheduler fields.  Now they must
              be viewed as valid for a particular processor type
              only.  For example, when processing the SRXBK for
              type zAAP, SRXMXSHR is the largest SHARE of system
              that can be delivered to a single VMDBK of type
              zAAP.
 
 
  SRXBK Control Block Content Top of page
 

 SRXBK DSECT Top of page
Hex Dec Type/Val Lng Label (dup) Comments ---- ---- --------- ---- -------------- -------- 0000 0 Structure SRXBK System Resource Management block extensions 0000 0 Signed 4 SRXDLSCN Dispatch list scan header. This is the point at which HCPSTK's LINKDS subroutine is to begin scanning the dispatch list for an insertion point whenever adding a user 0004 4 Address 4 SRXDLADD Pointer to the last VMDBK added to the D-list ahead of ATOD. Used to reduce scans in the list. Timing Parameters NOTES : The assembler construct 'FL8S12' is used to generate a fixed-point number which represents a time value (in microseconds) in TOD clock format or CPU timer format. 'FL8S12E6' is used when specifying a time value in seconds (rather than microseconds). 0008 8 Signed 8 SRXHIDSP Dispatching priority of the highest priority user on the dispatch list at the time of the last major reshuffle (HCPDSBRV) less an adjustment interval to allow for continuing transactions returning to the dispatch list. The highest priority user has the lowest value of VMDDPRTY. This field is the basis for computing field DSVPRIOR in the PLDV. DSVPRIOR = VMDDPRTY - SRXHIDSP. (at least 32 bits of the result). 0010 16 Signed 8 SRXATOD Artificial TOD. This TOD only advances at the rate the system is running user work. Updates serialized by SRMSLOCK exclusive or SRMSLOCK shared plus SRMATDLK exclusive. 0018 24 Signed 4 SRXTOTLS (0) An equate used as an index base to reference one of the next two fields, srmreldl and srmabsdl. Code depends on these two fields being fullwords and following IN THE GIVEN ORDER. 0018 24 Signed 4 SRXRELDL The sum of the relative shares of all RELATIVE share holders (excluding dedicated VMDBKs) currently in the dispatch list. This field is protected by the scheduler lock. 001C 28 Signed 4 SRXABSDL The sum of the absolute shares of all VMDBKs (excluding dedicated VMDBKs) currently in the dispatch list. This field is protected by the scheduler lock. 0020 32 Signed 4 SRXTOTDE (0) An equate used as an index base to reference one of the next two fields, srmrelde and srmabsde. Code depends on these two fields being fullwords and following in the given order. 0020 32 Signed 4 SRXRELDE The sum of the relative shares of all relative share holders currently in the eligible and dispatch list. This field is protected by the scheduler lock. 0024 36 Signed 4 SRXABSDE The sum of the absolute shares of all VMDBKs currently in the eligible and dispatch list. This field is protected by the scheduler lock. 0028 40 Signed 2 SRXNCPUA The number of CPUs available to schedule time on for non-dedicated users. This field is protected by the scheduler lock. 002A 42 Signed 2 SRXPKCNT The number of parked CPUs. 002C 44 Address 4 SRXLLIST Anchor for the limit-list. Contains address of 1st VMDBK in list, or zero if list is empty. VMDBKs are forward and backward chained via VMDLFPNT & VMDLBPNT. 0030 48 Dbl-Word 8 SRXATODD A timestamp (TOD). The deadline for current ATOD-interval to end. Each CPU will copy this into its PFXATODD. But PFXATODD will often be an iteration behind SRXATODD. Updates are serialized by SRMATDLK exclusive. 0038 56 Dbl-Word 8 SRXCHKIN A timestamp (TOD). Time when the first-checker CPU last checked in (to start current ATOD-interval). Equals PFXCHKIN of first-checker. Updates are serialized by SRMATDLK exclusive. 0040 64 Dbl-Word 8 SRXCHKTW A timestamp (TOD). Time when the tracked-wait masks (SRXASKT1 and SRXASKT2) should next be checked. (Set to something like TOD+10ms.) Updates are serialized by SRMATDLK exclusive. 0048 72 Signed 8 SRXATOD2 Artificial TOD2. This TOD advances at the same rate as the TOD clock. It is updated each time SRXATOD is adjusted. This field is used to determine when a VMDBK should be dropped from the limit list. Updates serialized by SRMATDLK exclusive. 0050 80 Bitstring 64 SRXASKTW Mask has a bit for each logical CPU. Bit is on if the CPU is currently in "tracked-wait" mode. Updates serialized by SRMSLOCK exclusive or SRMSLOCK shared plus SRMATDLK exclusive. 0090 144 Bitstring 64 SRXASKT1 Mask has a bit for each logical CPU. Bit is on if CPU performed an ATOD-check-in since mask was last reset (as timed by SRMASKTM). Updates are serialized by SRMATDLK exclusive. 00D0 208 Bitstring 64 SRXASKT2 Mask has a bit for each logical CPU. Bit is on if CPU performed an ATOD-check-in during previous interval (as timed by SRMASKTM). Updates are serialized by SRMATDLK exclusive. 0110 272 Signed 4 SRXTRKCT Count of tracked-wait-mode CPUs. Updates serialized by SRMSLOCK exclusive or SRMSLOCK shared plus SRMATDLK exclusive. 0114 276 Address 4 * Reserved for IBM use SRXRTHRU is a table used in normalizing users' VMDRTHRUs. (VMDRTHRU is the user's "required throughput" i.e., his SHARE after it has been adjusted to compensate him for any delay in the eligible list.) 0118 280 Signed 4 SRXRTHRU (0) Start of array (table) of sums of VMDRTHRU values for all VMDBKs in the dispatch list. 0118 280 Signed 4 SRXRTHRN Total VMDRTHRU of VMDBKs in the dispatch list which are not cur- rently hitting their max-SHAREs. 011C 284 Signed 4 SRXRTHRL Total VMDRTHRU of VMDBKs in the dispatch list which are current- ly hitting their max-SHAREs. (LIMITed and hitting the limit.) 0120 288 Signed 4 SRXRTHRZ (0) End of array (table). 0120 288 Signed 4 * (2) Reserved for IBM use General Data Fields 0128 296 Signed 4 SRXMXSHR Largest SHARE of system that can be delivered to a single VMDBK. It is the reciprocal of SRXNCPUA. (E.g., 0.25 on a 4-way system.) 012C 300 Signed 4 SRXLLCNT Count of adds to the limit-list. This count is only approximate, it does not include adds result- from virtual-MP priority drop. 0130 304 Signed 4 SRXCONLL Count of users actually ON the Limit List. This count is serialized by the scheduler lock. 0134 308 Address 4 SRXDVLST Anchor into the linked list of PLDV's linked by DSVNXTDV. The following fields are bit masks for which each real processor has a corresponding unique bit. 0138 312 Bitstring 64 SRXLCPUA Mask containing the logical CPU ids (PFXLCPUA) of CPUs which are online, non-dedicated, and unparked. (The difference of SRXNCPUA and SRXPKCNT should tell how many bits are on in SRXLCPUA.) See also SYSLCPUA, which is similar, but also shows dedicated, parked and also offline CPUs whose prefix pages have not been freed. 0178 376 Bitstring 64 SRXPKMSK Mask containing the logical CPU ids (PFXLCPUA) of CPUs which are parked. (The counter SRXPKCNT indicates how many bits are on in SRXPKMSK.) See also SRMPKMSK, which is a mask for parked CPUs of all types. 01B8 440 Address 4 SRXTRQWT Points to TRQBK used to bring us out of wait state when it is time to dequeue VMDBKs from limit-list. 01BC 444 Bitstring 1 SRXFLAGS General flags 1... .... SRXSYSMP X'80' SRXSYSMP This CPU type can dispatch SYSTEMMP work (CP + IFL) 01BD 445 Bitstring 1 SRXEXUSE SRM EXCESSUSE field 00000010 SRXEXHGH 16 SRXEXHGH -Indicates the system should be aggressive in using unentitled CPU/core capacity. 00000008 SRXEXMED 8 SRXEXMED -Indicates the system should be moderately aggressive in using unentitled CPU/core capacity. 00000001 SRXEXLOW 1 SRXEXLOW -Indicates the system should not be aggressive in using unentitled CPU/core capacity. 00000002 SRXEXNON 2 SRXEXNON -Indicates the system should not use unentitled CPU/core capacity. 01BE 446 Bitstring 1 SRXWRKCI Workload confidence interval - integer between 50 and 99, specifying the percentage confidence level 01BF 447 Bitstring 1 SRXTVCNF T/V ratio confidence percentage - integer between 50 and 99, specifying the confidence level of the T/V ratio ceiling projection. 01C0 448 Signed 4 SRXCPPAD SRM CPUPAD value, a scaled number where X'00010000' represents one CPU/core 01C4 452 Signed 2 SRXPMAX Maximum number of CPUS that can be parked in an interval 01C6 454 Bitstring 2 * Reserved for IBM use 01C8 456 Address 4 SRXLASDV HL address of the last DSVBK to which a VMDBK was assigned during the round-robin phase of rebalance which is used when all capacity of a given type is depleted. Reset at the start of each rebalance 01CC 460 Signed 4 SRXENTVM This is a scaled number between X'00000001' and X'00010000' representing the portion of a real CPU to which vertical medium CPUs are entitled. Serialized by Vary Proc lock. 01D0 464 Signed 4 SRXNOTVH Capacity assigned to all CPUs/cores other than vertical high CPUs/cores. 01D4 468 Bitstring 4 * Reserved for IBM use. 01D8 472 Dbl-Word 8 SRXNICPF (10) Circular array of Next Interval Capacity Factors. RCCTOPDX is to be used as an index to find the most recent element. Each element is a factor to be used to adjust the remaining capacity during the next interval. This value is stored in floating point format. 0228 552 Dbl-Word 8 SRXNIPAD (10) Circular array of Next Interval Tolerance Padding values. RCCTOPDX is to be used as an index to find the most recent element. Stored in floating point format. 0278 632 Signed 4 SRXLIUSG (10) Circular array of Total CPU usage of this type during the last interval. RCCTOPDX is to be used as an index to find the most recent element. This value is scaled such that x'10000' equals one full CPU. 02A0 672 Signed 4 SRXVMDCT (10) Circular array of counts of the number of VMDBKs on the global cyclic list with this dispatch CPU type when gathering informa- tion to be used for dispatch vector rebalance. RCCTOPDX is to be used as an index to find the most recent element. 02C8 712 Signed 4 SRXACGUS (10) Circular array of the average CPU usage of the VMDBKs of this type in the last interval. RCCTOPDX is to be used as an index to find the most recent element. This value is scaled such that x'10000' equals one full CPU. 02F0 752 Signed 4 SRXMCF Maximum Capacity Factor for this CPU type. MCF=1 when MT is not enabled or RCCACMNT=1 for the CPU type corresponding to this SRXBK. Scaled by HisMT_Entry_kMetricFactor or by shifting the value using HisMT_Entry_kMetricShift Updated only by a singleton task in HCPMTCMC. 02F4 756 Signed 4 SRXCORCT Count of cores of this CPU type with online non-dedicated parked and unparked processors. Serialized by the Scheduler lock. 00000020 SRXHISTSZ 32 Number of entries in scheduling history array 00000008 SRXNumInts 8 Number of entries in the scheduling history array that are actually used to track scheduling history 02F8 760 Dbl-Word 8 SRXATODHIST (32) History of ATOD values by scheduling interval 03F8 1016 Dbl-Word 8 SRXSCHEDINT Current scheduling interval number .... 1.1. SRXSCHEDINTLN 10 SRXSCHEDINTLN Length (in number of first-checker intervals) of a scheduling interval 0400 1024 Signed 4 SRXNXTINT Count of first-checks left until we start a new scheduling interval 0404 1028 Signed 4 * Reserved for IBM use 0408 1032 Signed 4 SRXTOTLG (0) Sum of shares for all logged on users. 0408 1032 Signed 4 SRXRELLG Sum of relative shares for all logged on VMDBKs. (excluding dedicated VMDBKs) 040C 1036 Signed 4 SRXABSLG Sum of absolute shares for all logged on VMDBKs. (excluding dedicated VMDBKs) 0410 1040 Signed 2 SRXNUMVH Count of VH CPUs/Cores of this CPU type reported for our partition by Diag x'204'. 0412 1042 Signed 2 SRXNUMVM Count of VM CPUs/Cores of this CPU type reported for our partition by Diag x'204'. 0414 1044 Signed 2 SRXNUMVL Count of VL CPUs/Cores of this CPU type reported for our partition by Diag x'204'. 0416 1046 Signed 2 * Reserved for IBM use. 00000083 SRXSIZE (*-SRXBK+7)/8 size in double words 00000418 SRXBSIZE SRXSIZE*8 size in bytes 00000005 SRXCSIZE (SRXBSIZE+255)/256 size in cache lines
 
 
  SRXBK Storage Layout Top of page
 
          
*** SRXBK - System Resource Management block extensions
*
*     +---------------------------+---------------------------+
*   0 |         SRXDLSCN          |         SRXDLADD          |
*     +---------------------------+---------------------------+
*   8 |                       SRXHIDSP                        |
*     +-------------------------------------------------------+
*  10 |                       SRXATOD                         |
*     +---------------------------+---------------------------+
*  18 |         SRXRELDL          |         SRXABSDL          |
*     +---------------------------+---------------------------+
*  20 |         SRXRELDE          |         SRXABSDE          |
*     +-------------+-------------+---------------------------+
*  28 |  SRXNCPUA   |  SRXPKCNT   |         SRXLLIST          |
*     +-------------+-------------+---------------------------+
*  30 |                       SRXATODD                        |
*     +-------------------------------------------------------+
*  38 |                       SRXCHKIN                        |
*     +-------------------------------------------------------+
*  40 |                       SRXCHKTW                        |
*     +-------------------------------------------------------+
*  48 |                       SRXATOD2                        |
*     +-------------------------------------------------------+
*  50 |                                                       |
*     =                       SRXASKTW                        =
*     |                                                       |
*     +-------------------------------------------------------+
*  90 |                                                       |
*     =                       SRXASKT1                        =
*     |                                                       |
*     +-------------------------------------------------------+
*  D0 |                                                       |
*     =                       SRXASKT2                        =
*     |                                                       |
*     +---------------------------+---------------------------+
* 110 |         SRXTRKCT          |///////////////////////////|
*     +---------------------------+---------------------------+
* 118 |         SRXRTHRN          |         SRXRTHRL          |
*     +---------------------------+---------------------------+
* 120 |///////////////////////////////////////////////////////|
*     +---------------------------+---------------------------+
* 128 |         SRXMXSHR          |         SRXLLCNT          |
*     +---------------------------+---------------------------+
* 130 |         SRXCONLL          |         SRXDVLST          |
*     +---------------------------+---------------------------+
* 138 |                                                       |
*     =                       SRXLCPUA                        =
*     |                                                       |
*     +-------------------------------------------------------+
* 178 |                                                       |
*     =                       SRXPKMSK                        =
*     |                                                       |
*     +---------------------------+------+------+------+------+
* 1B8 |         SRXTRQWT          |:FLAGS|:EXUSE|:WRKCI|:TVCNF|
*     +---------------------------+------+------+------+------+
* 1C0 |         SRXCPPAD          |  SRXPMAX    |/////////////|
*     +---------------------------+-------------+-------------+
* 1C8 |         SRXLASDV          |         SRXENTVM          |
*     +---------------------------+---------------------------+
* 1D0 |         SRXNOTVH          |///////////////////////////|
*     +---------------------------+---------------------------+
* 1D8 |                                                       |
*     =                       SRXNICPF                        =
*     |                                                       |
*     +-------------------------------------------------------+
* 228 |                                                       |
*     =                       SRXNIPAD                        =
*     |                                                       |
*     +-------------------------------------------------------+
* 278 |                                                       |
*     =                       SRXLIUSG                        =
*     |                                                       |
*     +-------------------------------------------------------+
* 2A0 |                                                       |
*     =                       SRXVMDCT                        =
*     |                                                       |
*     +-------------------------------------------------------+
* 2C8 |                                                       |
*     =                       SRXACGUS                        =
*     |                                                       |
*     +---------------------------+---------------------------+
* 2F0 |          SRXMCF           |         SRXCORCT          |
*     +---------------------------+---------------------------+
* 2F8 |                                                       |
*     =                     SRXATODHIST                       =
*     |                                                       |
*     +-------------------------------------------------------+
* 3F8 |                     SRXSCHEDINT                       |
*     +---------------------------+---------------------------+
* 400 |        SRXNXTINT          |///////////////////////////|
*     +---------------------------+---------------------------+
* 408 |         SRXRELLG          |         SRXABSLG          |
*     +-------------+-------------+-------------+-------------+
* 410 |  SRXNUMVH   |  SRXNUMVM   |  SRXNUMVL   |/////////////|
*     +-------------+-------------+-------------+-------------+
* 418
*
*** SRXBK - System Resource Management block extensions
 
 
  SRXBK Cross Reference Top of page
 
 
Symbol         Dspl Value
-------------- ---- -----
SRXABSDE       0024
SRXABSDL       001C
SRXABSLG       040C
SRXACGUS       02C8
SRXASKTW       0050
SRXASKT1       0090
SRXASKT2       00D0
SRXATOD        0010
SRXATODD       0030
SRXATODHIST    02F8
SRXATOD2       0048
SRXBSIZE       0416 00000418
SRXCHKIN       0038
SRXCHKTW       0040
SRXCONLL       0130
SRXCORCT       02F4
SRXCPPAD       01C0
SRXCSIZE       0416 00000005
SRXDLADD       0004
SRXDLSCN       0000
SRXDVLST       0134
SRXENTVM       01CC
SRXEXHGH       01BD 00000010
SRXEXLOW       01BD 00000001
SRXEXMED       01BD 00000008
SRXEXNON       01BD 00000002
SRXEXUSE       01BD
SRXFLAGS       01BC
SRXHIDSP       0008
SRXHISTSZ      02F4 00000020
SRXLASDV       01C8
SRXLCPUA       0138
SRXLIUSG       0278
SRXLLCNT       012C
SRXLLIST       002C
SRXMCF         02F0
SRXMXSHR       0128
SRXNumInts     02F4 00000008
SRXNCPUA       0028
SRXNICPF       01D8
SRXNIPAD       0228
SRXNOTVH       01D0
SRXNUMVH       0410
SRXNUMVL       0414
SRXNUMVM       0412
SRXNXTINT      0400
SRXPKCNT       002A
SRXPKMSK       0178
SRXPMAX        01C4
SRXRELDE       0020
SRXRELDL       0018
SRXRELLG       0408
SRXRTHRL       011C
SRXRTHRN       0118
SRXRTHRU       0118
SRXRTHRZ       0120
SRXSCHEDINT    03F8
SRXSCHEDINTLN  03F8 0A
SRXSIZE        0416 00000083
SRXSYSMP       01BC 80
SRXTOTDE       0020
SRXTOTLG       0408
SRXTOTLS       0018
SRXTRKCT       0110
SRXTRQWT       01B8
SRXTVCNF       01BF
SRXVMDCT       02A0
SRXWRKCI       01BE
 
This information is based on z/VM 7.3.0 Last updated on 22 Jun 2022 at 15:56:25 EDT.
Copyright IBM Corporation, 1990, 2022