Tomcat Large Number of Suspended Threads Incident.

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In software engineering, a large number of suspended threads in Tomcat is an incident type that occurs when a high number of threads are created but are blocked from executing. This can happen due to a variety of reasons, such as slow database queries, network latency, or resource contention. When this occurs, the system may become unresponsive or slow, causing a degradation in performance or even a complete system failure. It is important to investigate and resolve this issue as quickly as possible to ensure the system can continue to function properly.



Next Step

Identify the PID of the Tomcat process

Check the number of threads blocked in the JVM

Check the number of threads waiting on a monitor lock

Check the number of threads in the "TIMED_WAITING" state

Check the number of threads in the "RUNNABLE" state

Check the current heap usage of the Tomcat JVM

Check the current CPU usage for the Tomcat process


Tune the thread pool settings in Tomcat to prevent the creation of too many threads and limit the amount of time a thread is allowed to remain suspended.

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