Why Did My JVM Show 900% CPU? Uncovering Container Limit Misconfigurations

An 8‑year ops veteran investigates a night‑time alert showing 900% CPU usage, discovers that a JVM inside a Kubernetes pod misreads host cores while the container is limited to two CPUs, and outlines how improper thread‑pool settings and monitoring metrics caused massive throttling before presenting concrete fixes.

CPU throttlingJVMKubernetes

0 likes · 10 min read

Why Did My JVM Show 900% CPU? Uncovering Container Limit Misconfigurations

Liangxu Linux

Feb 7, 2024 · Cloud Native

How Docker Uses cgroups to Isolate CPU Resources

Docker leverages Linux cgroups to limit and schedule CPU usage per container, allowing you to set an upper bound on cores with the --cpus flag while keeping the actual cores dynamically allocated and leaving other system processes free to use the remaining CPUs.

Resource Managementcgroupscontainer limits

0 likes · 7 min read

How Docker Uses cgroups to Isolate CPU Resources

58 Tech

Sep 4, 2019 · Cloud Computing

Designing a Solution to Limit Container Thread Count in a Private Cloud Platform Using cgroup pids and inotify

This article analyzes the lack of thread‑count limits in a Kubernetes‑based private cloud platform, reproduces the issue with a Python multiprocessing script, and proposes a solution that combines the cgroup pids subsystem with inotify to enforce per‑container thread limits and provide real‑time alerts.

Kubernetescgroupcloud platform

0 likes · 8 min read

Designing a Solution to Limit Container Thread Count in a Private Cloud Platform Using cgroup pids and inotify