PFCDEFAULT

   On Alpha and Integrity servers during execution of programs,
   PFCDEFAULT controls the number of image pagelets read from
   disk per I/O operation when a page fault occurs. The PFCDEFAULT
   maximum default value is 2032 512-byte pagelets (127 8192-byte
   Alpha and Integrity server pages).

   The read I/O operations can take place from an image file or
   from the page file. The actual size of the cluster can be less
   than PFCDEFAULT, depending on the size of image sections and the
   pattern of page references.

   The value should not be greater than one-fourth the default size
   of the average working set to prevent a single page fault from
   displacing a major portion of a working set. Too large a value
   for PFCDEFAULT can hurt system performance. PFCDEFAULT can be
   overridden on an image-by-image basis with the CLUSTER option of
   the OpenVMS linker.

   PFCDEFAULT has the AUTOGEN and DYNAMIC attributes.