In the XCF Activity Report - Path Statistics, shown in Figure 3, the column labeled “RETRY” counts the number of times the signaling path was restarted and indicates the number of failures the signaling path has had. When this count is nonzero, it indicates that several attempts were made to send one or more messages. A message that cannot be sent on the first attempt suffers performance degradation. Even if all the messages were successfully sent before the path restart occurs (that is, all messages were sent on the first attempt), there may still be degraded performance for the signaling service because a path is not available for message transfer while it is being restarted. Thus, a path restart represents a loss of signaling capacity that may cause the message traffic to be distributed among fewer signaling paths, thereby degrading signaling performance.

Restarts can occur as systems enter and leave the sysplex, or as signaling paths in the sysplex are stopped and started. Barring these kinds of configuration changes, a high restart count suggests that signaling performance suffered because the path was not always operational. XCF automatically stops using a signaling path if path restarts occur so frequently that the device appears to be unusable.