Server connection management

A client CICS region establishes a cross-memory connection to a server the first time that a request refers to the pool for that server. A single connection is established to each server, regardless of the number of tables, queues, or counters that are accessed in the pool.

For coupling facility data table and temporary storage queue servers, a multi-threaded asynchronous connection is established. This connection allows requests to be overlapped up to a fixed maximum number of concurrent requests. Requests that exceed this maximum number are queued within the CICS region until a request thread becomes available.

For named counters, requests are processed synchronously, so only one request can be active at a time for a given client region TCB.

For information about managing failures in coupling facility connectivity, see the section about coupling facility connectivity recovery in z/OS Parallel Sysplex Recovery.