Natural uses work pools below and above the 16 MB line. In these
work pools, all temporary buffers physical storage requests are
satisfied.
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.
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.
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:
If a work pool is exhausted, another work pool of the specified work
pool size is allocated.
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.
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.
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.
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.
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.