To better understand the use of the Agent Auto-trim feature, consider a scenario involving a broker serving a client/server application running in stateless mode. Assume that the following property values are set:

When the broker starts, it starts 10 agents. This also marks the start of the first Agent/Server Auto-trim Interval. Assume that the broker is idle for 30 minutes (it is just before people arrive for work, for instance). At the end of the 30-minute interval, the highest number of agents that were busy at the same time would be zero. (Since there were no requests made of any of the agents, none of the agents was busy.) However, since zero is less than the Minimum Agent/Servers Instances value of 10, no automatic trimming takes place. This marks the start of the second interval.

As the second interval starts, employees begin their workday. There is a sudden demand for agents; in fact, the broker receives so many requests that it must start 20 additional agents. Assume that the high volume of workload, and demand on the agents, continues through the second interval. At the interval's end, the maximum number of busy agents is 30, which is the number the broker scaled up to in response to high demand. Thirty agents are running, and the maximum busy level is 30. No trimming occurs.

During the next interval, the request load diminishes somewhat. At the end of the interval, only 20 agents are concurrently busy. The maximum number of busy agents for the interval remains at 30, since 30 were busy at the start of the interval. Thirty agents are running, and the maximum busy level is 30. No trimming occurs.

Assume that all employees have to attend a company-wide meeting that begins midway through the interval. The highest number of agents busy at that same time was 20. At the end of the interval, there are 30 agents running, with zero agents currently busy. Since the maximum busy level is 20 (at the start of the interval), and the number of running agents is 30 (all are available since everyone is at the company meeting), the broker attempts to trim back the number of agents to 20.

Assume that the company meeting ran for another half-hour, and the entire next interval elapsed without any requests. The maximum busy agents would be zero, with 20 currently running. Since the Minimum Agent/Server Instances property value is set to 10, the broker attempts to trim back to 10 agents.

Keep in mind that the lower you set the Agent/Server Auto-trim Interval value, the more quickly the broker reacts to a drop in the workload. Under a reasonably steady work load, the broker should trim the number of running agents to the number needed. However, if the workload fluctuates a great deal and the Agent/Server Auto-trim Interval is set too low, the broker may trim agents that it must then restart. As stated earlier, repetitive trimming and restarting causes the system to waste resources on unnecessary process management.