MAXASSIZE is the maximum region size (in bytes) for an address space that was created by rlogind, telnetd, and other daemons. You can set a system-wide limit in BPXPRMxx and then set higher limits for individual processes. Use the RACF® ADDUSER or ALTUSER command to specify the ASSIZEMAX limit on a per-process basis as follows:

ALTUSER userid OMVS(ASSIZEMAX(nnnn)