Memory Leak Caused by Unremoved ThreadLocal Variables in Thread Pools

In my web app, I use ThreadLocal to store request metadata per thread. Over time, memory use steadily grows—even though threads finish processing. What's wrong?

With thread pooling, ThreadLocal values persist across requests until explicitly removed. If not cleared, these references accumulate, leading to memory leaks and eventually OutOfMemoryError ([turn0search5]turn0search13]turn0search1]). Fixes: • Always call .remove() in a finally block after request handling. • Avoid storing large objects per request in ThreadLocal. • Use request-scoped or dependency injection for per-request state instead.