top Troubleshooting High CPU in Linux¶
Introduction¶
Advanced top usage helps when the basic form is not enough. This article focuses on realistic command patterns that are useful during administration and troubleshooting.
When You Need Advanced Usage¶
Use top when you need a live view of CPU, memory, load average, and busy processes. It is available on almost every Linux server. Advanced usage is most useful when you need to narrow scope, work on multiple targets, or diagnose why the first command did not answer the question.
Practical Examples¶
Inspect first:
uptime
Run a focused command:
top -u apache
Use a real-world pattern:
top -b -n 1 | head
Troubleshooting¶
If top does not give the expected result, verify the target first with uptime. Then check permissions, paths, service state, network reachability, package repositories, or process state depending on what the command manages.
Example output:
10:00:00 up 5 days, 2:13, 2 users, load average: 0.22, 0.31, 0.28
Common Mistakes¶
- Killing a process based on one short CPU spike.
- Reading load average without considering CPU count.
- Ignoring memory pressure and focusing only on CPU.
Safety Notes¶
Use a preview, backup, dry run, read-only command, or smaller test target before applying broad, recursive, destructive, or remote operations.
Related Guides¶
Summary¶
Advanced top usage should still be controlled. Build the command step by step and verify the result separately.