Trace database queries for your session

Enable module#mod_server_storage if the Development page says it is needed for database tracing. On the Development page, enable Trace all database queries for the current session.

Reproduce one page load or action in that session and inspect the trace output. Look for repeated queries, unexpectedly large result sets, and queries that dominate the request time. A trace from another session may not include your request.

Turn tracing off when finished. Use the evidence to choose a query to investigate; do not add indexes based on query count alone.