hard20 pts · first answer countskubernetesperformancetroubleshooting

Java Pod OOMKilled with free heap

A Java service with a 2Gi memory limit and -XX:MaxRAMPercentage=90 is OOMKilled, yet heap graphs never pass 1.6Gi. Why?

A.The JVM ignores container memory limits in every version, so it sizes for the host.B.Kubernetes counts heap memory twice when the kubelet compares the container usage with its memory limit.C.Heap is only part of JVM memory; metaspace, threads, code cache and buffers push it over.D.MaxRAMPercentage only takes effect on Windows containers, so the heap is unbounded here.

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