Using CA Hyper-Buf › Dynamic Buffering Control Statements › Processing Constraints

Processing Constraints

You control the CA Hyper-Buf dynamic buffering using CNTLFILE control statements supplied to GVBDBFON when you initialize the system, or to GVBREFR after CA Hyper-Buf is initialized on your system. The general format of the control file is as follows:

SYSTEM_DEFAULTS
  (list of  system  default constraints)
  . . .
  . . .
MODE=(   INCLUDE  | EXCLUDE  )
  CLUSTER=ABC
  (list of  cluster ABC  constraints)
  JOB=PAY+
  (list of  constraints for job  names beginning with  'PAY')
  (other  mode control group  constraints)
  . . .
  . . .
MODE=(   EXCLUDE  | INCLUDE  )
  (other  mode control group  constraints)
  . . .

Indentation of the various control statements is optional. Controls are indented in these examples to facilitate visual perception of the hierarchy of the rules. The indentation does not affect the hierarchy. The hierarchy is fixed by CA Hyper-Buf.

There are two modes available, INCLUDE and EXCLUDE. EXCLUDE mode specifies levels which are exempt from CA Hyper-Buf control and follows normal VSAM buffer selection. INCLUDE specifies levels eligible for buffer modification by CA Hyper-Buf.

Within these two modes, you can specify LEVEL selectors. These allowable level selectors are shown below:

• CLUSTER=name
• SMSclass=name
• JOB=name
• PROGRAM=name
• DDNAME=name

The name fields represent constraint variables that are matched to the corresponding OPEN variables for each VSAM OPEN. For example, the JOBNAME of the job that is issuing the OPEN is compared to all of the JOB= level selectors by the CA Hyper-Buf OPEN intercept routine. Any constraints that are specified at a matching level affect the CA Hyper-Buf buffer calculations.

Within each of the levels you can specify buffering CONSTRAINTS. Constraints include maximum allowable BUFFERSPACE, BUFNI, and BUFND and corresponding minimum allowable values for BUFFERSPACE, BUFNI, and BUFND, as well as other tunable values. The constraints associated with each matched level selector are merged into a composite constraint table by the CA Hyper-Buf OPEN intercept routine.

All controls can be specified in free form. Only positions 1-72 of each control record are scanned for control information. Numeric fields, when required, can be suffixed by the letter K to indicate multiplication by 1024. For example, specifying 60K is equivalent to specifying 61440.

You must specify command/operand pairs on the same record. You cannot specify MAXBUFSP on one record, followed by 60K on the next record, and expect MAXBUFSP to be set to 60K. Both fields of the control must be on the same logical record of the control file. You can specify as many records as required to contain all of your controls.