Answer by Mike Bentley
There is no built-in limit to the number of users PRPC can handle. The practical limit depends on the amount of resources available to your system. Every requestor occupies a portion of memory (clipboard). At some point after numerous requestors have logged in, the server will run out of JVM memory. To estimate this number, you need to know the average size of a user's clipboard and the number of users. You can use the PAL (Performance) tool to learn the size in bytes of an operator's clipboard.

Requestors and the clipboard are discussed at varying detail in many Pegasystems courses. You can also get more information about the clipboard and requestors by reviewing Basics of clipboard structure and management.