Central storage

Control use of central storage space by carefully specifying the value for the TRKCELL parameter on the SPOOLDEF initialization statement. The following notes should assist you, if you experience central storage constraints.

Two copies of the checkpoint data set reside in virtual storage.
If your installation has a 3800-1 printer operated by JES2 and track-cell despooling and double buffering are in effect, the number of central storage frames is two times the value of TRKCELL during printing activity. (If you set the BUFSIZE= parameter on the SPOOLDEF statement to its lower limit, 1944, you only need TRKCELL= number of frames.)

Also, note that as your installation adds printers to its configuration, JES2 central storage requirements increase proportionally.

JES2 obtains the buffer storage requirements for printers operated by a functional subsystem from the functional subsystem address space private area and page-fixes the storage. Therefore, these buffers do not affect JES2 virtual storage usage, but they increase the use of central storage.