System logs ===> tomcat/

===> perflogs/

Tomcat / Application Server Logs (tomcat-stdOut.log):

1. Capture unexpected application-server errors.
2. Useful for troubleshooting Java exceptions and stack traces.
3. Can contain issues related to application startup and plug-ins.
4. For example, Appian documents errors such as a work poller being unable to obtain required threads.

Example:

If an Appian plug-in fails to load or the application server encounters a Java exception, the Tomcat logs can provide details about the error and its stack trace.

Performance Logs (APPIAN_HOME/logs/perflogs):

1. Used to analyze system performance and resource usage.
2. Engine performance logs provide metrics such as CPU idle time and foreground processing time.
3. Process execution logs help identify processes/models consuming significant resources.
4. Data store performance logs show database operations and their Prepare, Execute, and Transform times, including slow operations.
5. Appian also has interface performance logs for measuring interface interactions and evaluation times.

Example:

If a process model is taking longer than expected, performance logs can help identify whether the issue is related to process execution, database operations, or another Appian component.