Defining a private buffer pool using the DFSVSMxx IMS.PROCLIB member

You define a private buffer pool by specifying the DEDB statement in the DFSVSMxx member of the IMS.PROCLIB data set.

For example, the following two statements define two private buffer pools:

DEDB=(POOL1,512,400,50,800,LKASID)
DEDB=(POOL2,8196,100,20,400,NOLKASID)

The first statement defines a pool that has a buffer size of 512, with an initial allocation of 400 buffers, increasing by 50, as needed, to a maximum of 800. This pool is used as a local cache, and buffer lookaside is performed for areas that share this pool.

The second statement defines a pool that has a buffer size of 8K, with an initial allocation of 100 buffers, increasing by 20, as needed, to a maximum of 400. This pool is used in the same fashion as the common buffer pool. There will be no lookaside performed.

If the customer does not define a private buffer pool, the parameters and default parameter values in the following statement are used: 
DEDB=(poolname,XXX,64,16,512)
In the above statement:
  • Poolname is the CI size of the area to be opened in character format.
  • XXX is the CI size of the area to be opened.
  • The initial buffer allocation is 64.
  • The secondary allocation is 16.
  • The maximum number of buffers for the pool is 512.
  • The LKASID option is specified if it is specified in DBRC for the area.