WPSIZE - Sizes of Natural Work Pools

This Natural profile parameter specifies the sizes of the Natural work pools below and above the 16 MB line for one Natural session.

Possible settings See Syntax Description.
Default setting (32,128,2097151,2097151)  
Dynamic specification yes  
Specification within session no  

Notes:

  1. Natural uses work pools below and above the 16 MB line. In these work pools, all temporary buffers physical storage requests are satisfied.
  2. Natural uses physical storage in special situations only, for example, for passing parameter areas outside the thread (while the thread is released) during the execution of the CALL statement with the "call by value option" indicated by a SET CONTROL 'P=V' statement under CICS.
  3. The advantage of work pools is that, if there are many requests for physical storage, Natural can satisfy these requests by itself rather than by passing it to the operating system.

Syntax Description

The WPSIZE parameter is specified as follows:

WPSIZE=(size-below,size-above,maximum-below,maximum-above)

Where:

Syntax Element Explanation
size-below size-below (0-1024) is the size of one work pool in KB below the 16 MB line. The value 0 means that no work pool is allocated, i.e. all requests for physical storage below 16 MB are passed directly to the operating system.
size-above size-above (0-16384) is the size of one work pool in KB above the 16 MB line. The value 0 means that no work pool is allocated, that is, all requests for physical storage above 16 MB are passed directly to the operating system.
maximum-below maximum-below (0-2097151) limits the total physical storage in KB which can be allocated below the 16 MB line. The value 0 means no physical storage can be allocated below the 16 MB line.
maximum-above maximum-above (0-2097151) limits the total physical storage in KB which can be allocated above the 16 MB line. The value 0 means no physical storage can be allocated above the 16 MB line.

Notes:

  1. If a work pool is exhausted, another work pool of the specified work pool size is allocated.
  2. If the size of the requested physical storage is larger than the specified work pool size, a GETMAIN request for that larger size is made.
  3. Subparameters not to be changed can be omitted; for example, you can specify WPSIZE=(,1000) if you want to set the work pool size only above 16 MB to 1000 KB.
  4. Natural allocates the work pools outside the Natural storage thread according to the specified settings. A work pool is allocated during the first request for physical storage and is released during the next terminal I/O.
  5. For non-thread environments (for example, batch, TSO), the recommended setting is WPSIZE=(0,0). This may save virtual storage. Exception: This recommendation does not apply if the zIIP Enabler for Natural is installed and active.
  6. If the zIIP Enabler for Natural is installed and active (z/OS batch and TSO only), an appropriate setting of WPSIZE can reduce the number of switches into TCB mode, because of the reduced number of physical GETMAINs. The same applies if the profile parameter THSIZE is used.