Creation and Expiration of Server Processes

Automatic housekeeping facilities within the Dispatcher control the creation of new and expiration of old or idle server processes. The basic options that control the Dispatcher's behavior are MIN_PROCS and MAX_PROCS. MIN_PROCS provides a guaranteed level of service by having a number of server processes ready and waiting for incoming connections. MAX_PROCS, on the other hand, sets an upper limit on how many server processes may be concurrently active for the given service.

It is possible that a currently running server process might not be able to accept any connections because it is already handling the maximum number of connections of which it is capable, or because the process has been scheduled for termination. The Dispatcher may create additional processes to assist with future connections.

The MIN_CONNS and MAX_CONNS options provide a mechanism to help you distribute the connections among your server processes. MIN_CONNS specifies the number of connections that flags a server process as “busy enough” while MAX_CONNS specifies the “busiest” that a server process can be.

In general, the Dispatcher creates a new server process when the current number of server processes is less than MIN_PROCS or when all existing server processes are “busy enough” (the number of currently active connections each has is at least MIN_CONNS).

If a server process is killed unexpectedly, for example, by the UNIX system kill command, the Dispatcher still creates new server processes as new connections come in.

For information about configuring the Dispatcher, see Dispatcher Configuration File