Performance Meters

PerformanceMeter is a collection of callbacks that the implementation could know when a request is sent, arrives or is is processed.

As shown above, T1-T5 identifies the following callbacks.

• T1: PerformanceMeter.requestStartAtClient (String, Execution, long)
• T2: PerformanceMeter.requestStartAtServer(String, Execution, long)
• T3: PerformanceMeter.requestCompleteAtServer(String, Execution, long)
• T4: PerformanceMeter.requestReceiveAtClient(String, Execution, long)
• T5: PerformanceMeter.requestCompleteAtClient(String, Execution, long)

Thus,

• Server Execution Time: T3 - T2
• Client Execution Time: T5 - T4
• Network Latency Time: (T4 - T3) + (T2 - T1)

Notice that, when we make a connection to load a page for the first time, only Server Execution Time is available. T4 and T5 will be saved on the client-side and sent back along with the next request.

Register as a Listener

Once implemented, you need to register it as a listener in WEB-INF/zk.xml (assume the class is called foo.MyMeter):

    <listener>
        <listener-class>foo.MyMeter</listener-class>
    </listener>