There are multiple ways to determine the cause of problems occurring in a web application.
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You can use:
Builder call timing tracing
To track down bugs in a model or application. The Debug Tracing builder allows you to trace variables and actions. This builder writes trace information to a log file allowing you review the logged trace output after you have run a model.
By default this log file is given the following name:
You can analyze the time that builder calls take during regeneration. Use the builderCallTiming property in the log4j.properties file. Diagnostic tracing
If your application has memory problems during development, set diagnostic trace properties to determine whether you have too much data in the session. Diagnostic tracing is typically not used in production environments. Designer Task view
To review errors and warnings that result from the builder generation code.Application Server console