server-performance-stats

Lightweight shell script to report basic server performance statistics.

Features

• Total CPU usage
• Total memory usage (Used vs Free + percentage)
• Total disk usage (Used vs Free + percentage)
• Top 5 processes by CPU usage
• Top 5 processes by memory usage

The script is Linux-first (reads /proc) but includes fallbacks for macOS (Darwin). It aims to be dependency-light and usable on most servers.

Requirements

• POSIX-compatible shell (bash recommended)
• Common system utilities: ps, df, awk, sed, top, vm_stat (macOS), sysctl (macOS)
• numfmt (optional) improves human-readable memory/disk formatting; the script falls back to simple units if numfmt is missing.

Quick start

1. Make the script executable:

chmod +x server-stats.sh

2. Run it:

./server-stats.sh

Example output (trimmed):

========== Server Performance Summary (OS: Linux) ==========
Total CPU usage: 7.2%

========== Memory ==========
Total: 15.56 GiB
Used:  3.12 GiB (20.0%)
Free:  12.44 GiB

========== Disk (aggregated/primary) ==========
Total: 250.00 GiB
Used:  30.50 GiB (12%)
Free:  219.50 GiB

========== Top 5 processes by CPU ==========
PID  %CPU %MEM USER  COMM
... (top 5 rows) ...

Notes and troubleshooting

• Linux systems: the script reads /proc/stat and /proc/meminfo for accurate CPU and memory metrics.
• macOS: the script parses top, vm_stat, and sysctl. macOS top output formats can vary across versions and locales — if CPU% appears incorrect on macOS, inspect top -l 2 -s 0.5 | grep "CPU usage" to see how your system prints CPU usage.
• Containers/minimal images: some minimal containers may lack ps, df, or /proc entries; the script will print N/A or fall back to available tools when that happens.

Testing within a Linux image:

# Build docker image
docker build --debug --no-cache --tag debian-server:latest .

# Run docker container
docker run -it --name debian-server debian-server:latest /bin/bash

# Run script
./server-stats.sh