Valid values are between 20 and 100. You should change the value only at the direction of Informatica Global Customer Support. Decreasing the value to 20 might allow more tasks to start before the Listener suspends incoming connections. However, the lower value increases the possibility of memory-related S878 abends. Increasing the value to 100 reduces the risk of S878 abends but also reduces the number of tasks that can be accepted before the Listener suspends incoming connections. The optimal setting should allow the PowerExchange Listener to handle at least 140 tasks without memory abends.