For rising memory, take a heap dump (jcmd <pid> GC.heap_dump) and analyze in Eclipse MAT to find dominators. For high CPU, take repeated thread dumps (jstack) or use async-profiler to produce a flame graph showing hot methods. Enable GC logging to distinguish a leak from GC thrash.

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Interview Tip

Name the tools: jcmd/jmap, MAT, async-profiler.

jvmheap-dumpprofiling

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