In Part I of this Session Tracing Series we learned how to set the CLIENT_IDENTIFIER session variable and how we could query it from the V$SESSION view. We also looked at how to look at the resources consumed in real-time for that CLIENT_IDENTIFER so that we could determine if large amounts of resources were attributed to a unique or group of client connections. If you remember from Part I, we invoked a logon trigger whenever a session connected and then queried the V$SESSION view. This gave us output similar to that of Listing 1. From this output you can see a CLIENT_IDENTIFIER that is being set, I changed the logon trigger to put in host name instead of IP address in this example, and you can see that the module name did get populated for the applications I used to connect from (SQL*Plus and Oracle Administrative Assistant). Also note that the action field is blank. Also notice that the there are two connections using SQL*Plus from host FINE-ALE and one connection from host PAULANER.

Read more at: Oracle Session Tracing Part II