It is obviously very important to generate events when there is some sort of problem. It is also important to limit the number of events generated to prevent an excessive load on your network and your event management system.
For example, if your utilization on a link rapidly changes, it may cross a threshold many times and generate lots of events. Similarly, if a WAN link is changing from up to down and back rapidly (flapping), many events will be generated by a threshold on this interface.
You can control the rate at which events are generated in the following ways:
Lengthening the sample rate
The following three sections cover these techniques in detail.
Throttling events ...