UCloud Tech

Sep 20, 2018 · Operations

Why CPU Monitoring Shows 0% or 100% Spikes and How Hot Patches Fixed It

The article investigates intermittent CPU usage spikes on Linux servers caused by a kernel cputime bug, explains the root‑cause analysis, describes a cold patch applied to newer kernels, and details a hot‑patch solution that safely resolves the issue across thousands of production machines.