Capture Performance Logs With nmon

Record system metrics to a CSV for offline analysis.

LinuxProcessesmonitoringperformanceLow risk

Run nmon -f -s 1 -c 60 -m /tmp to log once per second for 60 samples.

01Command

Command

$ nmon -f -s 1 -c 60 -m /tmp

02What it does

nmon samples CPU, memory, disk and network and can write a delimiter-separated file that its analyzer or a spreadsheet reads, which is ideal for long unattended captures on a server. Interactive monitors cannot run headless this way.

03Risk

RiskLow risk

Requirementssudo apt install nmon

!Warning: Some metrics require root to read; ensure the capture runs with the privileges it needs and rotate old logs.

04Undo

✓No undo needed — this command does not change persistent state.

05Sources

nmon.1.en.html manual page (Debian bookworm)
Debian · technical · 2026-09-20
Evidence: Documents nmon and its -f file mode and -s/-c sampling options.

Last verified: 2026-10-13 · Category: System & Settings

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Check RAM Usage with free -h

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Use free -h to see used, free, and available memory plus swap in GB/MiB instead of raw kilobytes.

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Watch live CPU and memory usage per process with htop

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Launch an interactive process viewer with color meters for CPU cores, memory, and swap, plus search, sort, and kill controls.

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