To handle high volumes of inbound requests, you can write servers that perform multi-tasking (see Multi-Tasking Servers), or, if transaction program activity exceeds the capacity of a single server address space, you can start additional server address spaces to serve the same allocate queue. The initial server can use callable services to determine the transaction program load, and then start a new "copy" of itself if appropriate.

Figure 1 shows two server address spaces serving the same allocate queue:

Figure 1. Flow of Inbound Conversations to Multiple Server Address Spaces

Note that APPC/MVS does not attempt to balance the transaction program requests among address spaces.

Server address spaces must be started before they can serve any of the transaction programs they are to serve (that is, there is no demand scheduling of server address spaces).