If more memory is available at night, you can increase buffer pool sizes for that time to take advantage of the extra CPU available. For both of these examples, dynamic tuning makes it easier to take advantage of opportunities to improve MQSeries performance without affecting MQSeries availability itself. But with MQSeries as it is now, you cannot simply cancel the thread without affecting an underlying application or MQSeries. Or canceling an IMS thread means taking down the IMS message region. In many cases, even if problem threads are affecting MQSeries, it is not possible to shut down CICS or IMS immediately.
Users have to live with the poor performance until the problem can be addressed.
Dynamic tuning lets you resolve these resource-contention problems by giving you the ability to release just the resource causing the problem. For example, performance may be slow if you have MQSeries active logs on DASD with other data sets that have a lot of contention. Through dynamic tuning you can add new active logs on DASD that is not as busy. Performance improves and log files remain safe and available. Operations Issues Operations issues deal with giving you more control, or greater ability to make and effect decisions about MQSeries in real time.