Advanced Program-to-Program Communication/MVS (APPC/MVS) is the MVS™ support for cooperative processing. For example, an APPC/MVS administrator defines a host program to process user requests. A user of a PS/2 can run a PS/2 program to interact with this host program. APPC/MVS allows the PS/2 user to access host system (MVS) data without having to log on to the MVS system directly. This data can reside on more than one system, and can be maintained in distributed databases.
The host and PS/2 programs communicate using APPC/MVS services, and are called transaction programs (TPs). The interaction between the PS/2 TP and the host TP is called a conversation. After the conversation is established, each “partner” in the conversation can send data to, or receive data from, the other partner. Each partner in a conversation is identified by its logical unit name (LU name) which is the VTAM® “port” on the system, through which communication flows.
APPC/MVS work consists of inbound and outbound conversations. From an MVS point of view, an inbound conversation originates from a TP that requests service of an MVS TP. The requesting TP may be external to MVS (remote — such as a PS/2 program) or internal to MVS (local — such as TSO/E users or batch jobs). An outbound conversation originates from an MVS TP to another TP. See Recording SMF Information for APPC/MVS Work for information that SMF collects for inbound and outbound conversations.
SMF accounts for each TP scheduled by the APPC/MVS transaction scheduler (ASCH) as a single accountable entity, in the same way that batch jobs or TSO/E sessions are accountable entities. Your installation can collect, sort, and report on TP resources by using methods similar to those used for other work.
SMF also accounts for each conversation (inbound or outbound) in the system as a single accountable entity. Conversation-level accounting is particularly useful when your installation uses an APPC/MVS server application to process multiple conversations concurrently. Conversation level accounting allows your installation to collect information for each conversation in the server address space.
Note!
SMF does not produce records 4, 5, 20, 34, 35 for TPs.
To use APPC conversation information and APPC/MVS transaction records, your installation must customize any accounting packages that read the SMF records.