Adding Specific Selection Criteria

Sample Control Streams › Adding Specific Selection Criteria

Adding Specific Selection Criteria

In this example, notice that the control statements are free form. Some of the constraint controls are specified on the same line or on the same logical record as their owning level selector. Others are specified on separate lines. Some have a single constraint per line; others have multiple constraints on the same line. All of these specifications are valid.

SYSTEM * begin defaults

	MAXBUFSP=100K		*  maximum  per  file

	MAXBUFND=12		*  maximum  per  file

	MAXBUFNI=8		*  maximum  per  file

CUSHION=100K * leave this much after OPEN

	DEFAULTMODE=INCLUDE	*  all    included

* unless excluded

CLUSTER=PAY+

	MAXBUFSP=100K    MAXBUFND=22	***  override defaults

PROGRAM=PAYBACK    MAXBUFSP=100K

	CUSHION=150K

	DDNAME=INMSTR  MAXBUFND=40

JOB=P56673

	MAXBUFSP=32K    MAXBUFND=5

CLUSTER=PAYROLL.MASTER.FILE

	MAXBUFNI=12

MODE=EXCLUDE		*  the   following are

* exempt from buffering

	JOB=A2276

	PROGRAM=DFH+

In addition, notice that the JOB, CLUSTER, and PROGRAM level selectors are specified in whatever order is convenient for you. The order that the constraints are checked is determined by the defined hierarchy of the LEVEL SELECTORS, not by the order in which you specify the selectors. You can group all CLUSTER levels together, or group all levels pertaining to a particular application system together. The composite constraint table is the same in either case.

Moreover, since the LEVEL SELECTORS are independent entities, the CLUSTER=PAYROLL.MASTER.FILE level selector constraints apply to any job or program that opens this cluster (assuming that no explicit EXCLUDE is coded); not just to JOB=P56683.

This control stream specifies the same defaults as the previous example. However, the clusters, jobs, and programs that are listed before the MODE=EXCLUDE card are dynamically buffered (unless accessed by job A2276 or programs that start with DFH, which are the only EXCLUDE MODE selectors). The overrides specified with the selectors will override the default constraint values when matched at OPEN time.

If cluster PAYROLL.MASTER.FILE is opened by job X33876 which executes program H55667, MAXBUFNI is 12 (override), MAXBUFSP is 60K (default), and MAXBUFND is 12 (default). These are the limits honored by CA Hyper-Buf at OPEN time.

In another example, assume that job A2276 or program DFHSIP OPEN this same file. In this case, no dynamic buffering occurs. Both the job and program names match an EXCLUDE mode control group entry, which takes precedence over all other controls.

Finally, if job P56673, program PAYBACK, OPENs PAYROLL.MASTER.FILE on the INMSTR DD card, the following occurs:

The composite constraint table is initialized with the system default values
MAXBUFSP=100K, MAXBUFND=12, MAXBUFNI=8, CUSHION=100K.
Cluster selectors are compared against the cluster name. A match occurs, so any specified constraints are overridden. Result: MAXBUFSP=100K, MAXBUFND=12, MAXBUFNI=12, CUSHION=100K.
JOB selectors are compared against the job name. Again, a match. Result: MAXBUFSP=32K, MAXBUFND=5, MAXBUFNI=12, CUSHION=100K.
The PROGRAM selectors are compared against the program name. Again, a match. Result: MAXBUFSP=100K, MAXBUFND=5, MAXBUFNI=12, CUSHION=150K.
The DDNAME selectors are compared against the ddname. Result: MAXBUFSP=100K, MAXBUFND=40, MAXBUFNI=12, CUSHION=150K.

The above example is not intended to demonstrate numbers that you might want to use in your controls. These numbers were chosen to demonstrate the process that CA Hyper-Buf uses to set the limits that are in effect for any particular OPEN. You can specify any values that you choose for any of the jobs, programs, and clusters in your shop.