What is an Adaptive Session in AppDynamics?

An Adaptive Session (sometimes called a Diagnostic Session) is a temporary, more aggressive data-collection mode AppDynamics switches a Business Transaction into when it detects a recurring or worsening performance pattern, rather than relying on the normal, lighter sampling used during healthy operation.

During an adaptive session, the agent lowers its snapshot-capture thresholds and increases capture frequency for the affected Business Transaction, which means it gathers a denser set of call graphs, thread dumps, and diagnostic data specifically while the problem is actively occurring — exactly the window where troubleshooting data is most valuable and hardest to get after the fact.

This matters because always collecting maximum diagnostic detail for every transaction would create unsustainable overhead and storage costs; adaptive sessions let AppDynamics apply that heavier collection only when a real anomaly justifies the extra cost, then automatically taper back to normal sampling once the transaction returns to baseline health.