Use MAXPIPEUSER to set the maximum number of named or unnamed pipes that a user (that is, a UID) can open and use concurrently. By limiting the number of pipes that a user can open, you limit the amount of the pipe system resources that a user can use at one time.

The MAXPIPEUSER limit is a hard limit and applies to all non UID=0 users. The MAXPIPEUSER value cannot be changed on a user basis, and there is no resource limit (setrlimit) support to alter a soft or hard limit. For UID=0 users, the MAXPIPEUSER limit of 8,730 (the maximum allowable value) is always enforced.

The MAXPIPEUSER value can be changed dynamically using the SETOMVS command. For more information, see Dynamically changing the BPXPRMxx parameter values.