How to Diagnose High CPU Usage on Linux: A Step‑by‑Step Guide
This guide walks you through checking CPU utilization, system load, process resource consumption, tracing problematic processes, reviewing logs, and using performance tools to pinpoint and resolve high CPU usage on a Linux server.
1. Check CPU Utilization
Run top or htop to view per‑process CPU usage; if overall CPU usage exceeds 80 %, further investigation is required.
2. Check System Load
Execute uptime to see the load average. If the load is more than twice the number of CPU cores, the system is considered overloaded.
3. Inspect Process Resource Consumption
Identify the offending process and examine its resource usage with pidstat -p <pid> 1, which reports CPU, memory, and other metrics each second.
4. Trace the Problematic Process
Use strace -p <pid> to capture all system calls and return values of the process, helping locate the exact cause of high resource usage.
5. Review System Logs
Check the log files /var/log/messages and /var/log/syslog. For real‑time monitoring you can run tail -f /var/log/messages /var/log/syslog to see the latest entries.
6. Identify System Bottlenecks
Use performance analysis tools such as perf top to display functions that consume the most CPU time in real time, revealing underlying bottlenecks.
Signed-in readers can open the original source through BestHub's protected redirect.
This article has been distilled and summarized from source material, then republished for learning and reference. If you believe it infringes your rights, please contactand we will review it promptly.
Liangxu Linux
Liangxu, a self‑taught IT professional now working as a Linux development engineer at a Fortune 500 multinational, shares extensive Linux knowledge—fundamentals, applications, tools, plus Git, databases, Raspberry Pi, etc. (Reply “Linux” to receive essential resources.)
How this landed with the community
Was this worth your time?
0 Comments
Thoughtful readers leave field notes, pushback, and hard-won operational detail here.