Managing multiple servers can be a daunting task, especially when striving for consistency and efficiency. To tackle this challenge, I developed a robust automation system using Ansible, GitHub Actions, and Vagrant. This setup not only streamlines server configuration but also ensures that deployments are repeatable and maintainable.
A Bit of History: How It All Started
This project began out of necessity. I was maintaining a handful of Ubuntu servers — one for email, another for a website, and a few for experiments — and I quickly realized that logging into each one to make manual changes was both tedious and error-prone. My first step toward automation was a collection of shell scripts. They worked, but as the infrastructure grew, they became hard to manage and lacked the modularity I needed.
That is when I discovered Ansible. I created the ansible-servers repository in early 2024 as a way to centralize and standardize my infrastructure automation. Initially, it only contained a basic playbook for setting up users and updating packages. But over time, it evolved to include multiple roles, structured inventories, and eventually CI/CD integration through GitHub Actions.
Every addition was born out of a real-world need. When I got tired of testing changes manually, I added Vagrant to simulate my environments locally. When I wanted to be sure my configurations stayed consistent after every push, I integrated GitHub Actions to automate deployments. When I noticed the repo growing, I introduced linting and security checks to maintain quality.
The repository has grown steadily and organically, each commit reflecting a small lesson learned or a new challenge overcome.
The Foundation: Ansible Playbooks
At the core of my automation strategy are Ansible playbooks, which define the desired state of my servers. These playbooks handle tasks such as installing necessary packages, configuring services, and setting up user accounts. By codifying these configurations, I can apply them consistently across different environments.
To manage these playbooks, I maintain a structured repository that includes:
Inventory Files: Located in the inventory directory, these YAML files specify the hosts and groups for deployment targets.
Roles: Under the roles directory, I define reusable components that encapsulate specific functionalities, such as setting up a web server or configuring a database.
Configuration File: The ansible.cfg file sets important defaults, like enabling fact caching and specifying the inventory path, to optimize Ansible’s behavior.
Seamless Deployments with GitHub Actions
To automate the deployment process, I leverage GitHub Actions. This integration allows me to trigger Ansible playbooks automatically upon code changes, ensuring that my servers are always up-to-date with the latest configurations.
One of the key workflows is Deploy to Production, which executes the main playbook against the production inventory. This workflow is defined in the ansible-deploy.yml file and is triggered on specific events, such as pushes to the main branch.
Additionally, I have set up other workflows to maintain code quality and security:
Super-Linter: Automatically checks the codebase for syntax errors and adherence to best practices.
Dependabot Updates: Keeps dependencies up-to-date by automatically creating pull requests for new versions.
Local Testing with Vagrant
Before deploying changes to production, it is crucial to test them in a controlled environment. For this purpose, I use Vagrant to spin up virtual machines that mirror my production servers.
This approach allows me to validate changes in a safe environment before applying them to live servers.
Embracing Open Source and Continuous Improvement
Transparency and collaboration are vital in the open-source community. By hosting my automation setup on GitHub, I invite others to review, suggest improvements, and adapt the configurations for their own use cases.
The repository is licensed under the MIT License, encouraging reuse and modification. Moreover, I actively monitor issues and welcome contributions to enhance the system further.
In summary, by combining Ansible, GitHub Actions, and Vagrant, I have created a powerful and flexible automation framework for managing my servers. This setup not only reduces manual effort but also increases reliability and scalability. I encourage others to explore this approach and adapt it to their own infrastructure needs. What began as a few basic scripts has now evolved into a reliable automation pipeline I rely on every day.
If you are managing servers and find yourself repeating the same configuration steps, I invite you to check out the ansible-servers repository on GitHub. Clone it, explore the structure, try it in your own environment — and if you have ideas or improvements, feel free to open a pull request or start a discussion. Automation has made a huge difference for me, and I hope it can do the same for you.
In my previous post, I shared the story of why I needed a new USB stick and how I used ChatGPT to write a benchmark script that could measure read performance across various methods. In this follow-up, I will dive into the technical details of how the script evolved—from a basic prototype into a robust and feature-rich tool—thanks to incremental refinements and some AI-assisted development.
Starting Simple: The First Version
The initial idea was simple: read a file using dd and measure the speed.
No cache flushing, leading to inflated results when repeating the measurement
With ChatGPT’s help, I started addressing each of these issues one by one.
Tools check
On a default Ubuntu installation, some tools are available by default, while others (especially benchmarking tools) usually need to be installed separately.
Tools used in the script:
Tool
Installed by default?
Needs require?
hdparm
❌ Not installed
✅ Yes
dd
✅ Yes
❌ No
pv
❌ Not installed
✅ Yes
cat
✅ Yes
❌ No
ioping
❌ Not installed
✅ Yes
fio
❌ Not installed
✅ Yes
lsblk
✅ Yes (in util-linux)
❌ No
awk
✅ Yes (in gawk)
❌ No
grep
✅ Yes
❌ No
basename
✅ Yes (in coreutils)
❌ No
find
✅ Yes
❌ No
sort
✅ Yes
❌ No
stat
✅ Yes
❌ No
This function ensures the system has all tools needed for benchmarking. It exits early if any tool is missing.
This was the initial version:
check_required_tools() {
local required_tools=(dd pv hdparm fio ioping awk grep sed tr bc stat lsblk find sort)
for tool in "${required_tools[@]}"; do
if ! command -v "$tool" &>/dev/null; then
echo "❌ Required tool '$tool' is not installed."
exit 1
fi
done
}
That’s already nice, but maybe I just want to run the script anyway if some of the tools are missing.
This is a more advanced version:
ALL_TOOLS=(hdparm dd pv ioping fio lsblk stat grep awk find sort basename column gnuplot)
MISSING_TOOLS=()
require() {
if ! command -v "$1" >/dev/null; then
return 1
fi
return 0
}
check_required_tools() {
echo "🔍 Checking required tools..."
for tool in "${ALL_TOOLS[@]}"; do
if ! require "$tool"; then
MISSING_TOOLS+=("$tool")
fi
done
if [[ ${#MISSING_TOOLS[@]} -gt 0 ]]; then
echo "⚠️ The following tools are missing: ${MISSING_TOOLS[*]}"
echo "You can install them using: sudo apt install ${MISSING_TOOLS[*]}"
if [[ -z "$FORCE_YES" ]]; then
read -rp "Do you want to continue and skip tests that require them? (y/N): " yn
case $yn in
[Yy]*)
echo "Continuing with limited tests..."
;;
*)
echo "Aborting. Please install the required tools."
exit 1
;;
esac
else
echo "Continuing with limited tests (auto-confirmed)..."
fi
else
echo "✅ All required tools are available."
fi
}
Device Auto-Detection
One early challenge was identifying which device was the USB stick. I wanted the script to automatically detect a mounted USB device. My first version was clunky and error-prone.
detect_usb() {
USB_DEVICE=$(lsblk -o NAME,TRAN,MOUNTPOINT -J | jq -r '.blockdevices[] | select(.tran=="usb") | .name' | head -n1)
if [[ -z "$USB_DEVICE" ]]; then
echo "❌ No USB device detected."
exit 1
fi
USB_PATH="/dev/$USB_DEVICE"
MOUNT_PATH=$(lsblk -no MOUNTPOINT "$USB_PATH" | head -n1)
if [[ -z "$MOUNT_PATH" ]]; then
echo "❌ USB device is not mounted."
exit 1
fi
echo "✅ Using USB device: $USB_PATH"
echo "✅ Mounted at: $MOUNT_PATH"
}
After a few iterations, we (ChatGPT and I) settled on parsing lsblk with filters on tran=usb and hotplug=1, and selecting the first mounted partition.
We also added a fallback prompt in case auto-detection failed.
detect_usb() {
if [[ -n "$USB_DEVICE" ]]; then
echo "📎 Using provided USB device: $USB_DEVICE"
MOUNT_PATH=$(lsblk -no MOUNTPOINT "$USB_DEVICE")
return
fi
echo "🔍 Detecting USB device..."
USB_DEVICE=""
while read -r dev tran hotplug type _; do
if [[ "$tran" == "usb" && "$hotplug" == "1" && "$type" == "disk" ]]; then
base="/dev/$dev"
part=$(lsblk -nr -o NAME,MOUNTPOINT "$base" | awk '$2 != "" {print "/dev/"$1; exit}')
if [[ -n "$part" ]]; then
USB_DEVICE="$part"
break
fi
fi
done < <(lsblk -o NAME,TRAN,HOTPLUG,TYPE,MOUNTPOINT -nr)
if [ -z "$USB_DEVICE" ]; then
echo "❌ No mounted USB partition found on any USB disk."
lsblk -o NAME,TRAN,HOTPLUG,TYPE,SIZE,MOUNTPOINT -nr | grep part
read -rp "Enter the USB device path manually (e.g., /dev/sdc1): " USB_DEVICE
fi
MOUNT_PATH=$(lsblk -no MOUNTPOINT "$USB_DEVICE")
if [ -z "$MOUNT_PATH" ]; then
echo "❌ USB device is not mounted."
exit 1
fi
echo "✅ Using USB device: $USB_DEVICE"
echo "✅ Mounted at: $MOUNT_PATH"
}
Finding the Test File
To avoid hardcoding filenames, we implemented logic to search for the latest Ubuntu ISO on the USB stick.
find_ubuntu_iso() {
# Function to find an Ubuntu ISO on the USB device
find "$MOUNT_PATH" -type f -regextype posix-extended \
-regex ".*/ubuntu-[0-9]{2}\.[0-9]{2}-desktop-amd64\\.iso" | sort -V | tail -n1
}
Later, we enhanced it to accept a user-provided file, and even verify that the file was located on the USB stick. If it was not, the script would gracefully fall back to the Ubuntu ISO search.
find_test_file() {
if [[ -n "$TEST_FILE" ]]; then
echo "📎 Using provided test file: $(basename "$TEST_FILE")"
# Check if the provided test file is on the USB device
TEST_FILE_MOUNT_PATH=$(realpath "$TEST_FILE" | grep -oP "^$MOUNT_PATH")
if [[ -z "$TEST_FILE_MOUNT_PATH" ]]; then
echo "❌ The provided test file is not located on the USB device."
# Look for an Ubuntu ISO if it's not on the USB
TEST_FILE=$(find_ubuntu_iso)
fi
else
TEST_FILE=$(find_ubuntu_iso)
fi
if [ -z "$TEST_FILE" ]; then
echo "❌ No valid test file found."
exit 1
fi
if [[ "$TEST_FILE" =~ ubuntu-[0-9]{2}\.[0-9]{2}-desktop-amd64\.iso ]]; then
UBUNTU_VERSION=$(basename "$TEST_FILE" | grep -oP 'ubuntu-\d{2}\.\d{2}')
echo "🧪 Selected Ubuntu version: $UBUNTU_VERSION"
else
echo "📎 Selected test file: $(basename "$TEST_FILE")"
fi
}
Read Methods and Speed Extraction
To get a comprehensive view, we added multiple methods:
Parsing their outputs proved tricky. For example, pv outputs speed with or without spaces, and with different units. We created a robust extract_speed function with regex, and a speed_to_mb function that could handle both MB/s and MiB/s, with or without a space between value and unit.
extract_speed() {
grep -oP '(?i)[\d.,]+\s*[KMG]i?B/s' | tail -1 | sed 's/,/./'
}
speed_to_mb() {
if [[ "$1" =~ ([0-9.,]+)[[:space:]]*([a-zA-Z/]+) ]]; then
value="${BASH_REMATCH[1]}"
unit=$(echo "${BASH_REMATCH[2]}" | tr '[:upper:]' '[:lower:]')
else
echo "0"
return
fi
case "$unit" in
kb/s) awk -v v="$value" 'BEGIN { printf "%.2f", v / 1000 }' ;;
mb/s) awk -v v="$value" 'BEGIN { printf "%.2f", v }' ;;
gb/s) awk -v v="$value" 'BEGIN { printf "%.2f", v * 1000 }' ;;
kib/s) awk -v v="$value" 'BEGIN { printf "%.2f", v / 1024 }' ;;
mib/s) awk -v v="$value" 'BEGIN { printf "%.2f", v }' ;;
gib/s) awk -v v="$value" 'BEGIN { printf "%.2f", v * 1024 }' ;;
*) echo "0" ;;
esac
}
Dropping Caches for Accurate Results
To prevent cached reads from skewing the results, each test run begins by dropping system caches using:
sync && echo 3 | sudo tee /proc/sys/vm/drop_caches
What it does:
Command
Purpose
sync
Flushes all dirty (pending write) pages to disk
echo 3 > /proc/sys/vm/drop_caches
Clears page cache, dentries, and inodes from RAM
We wrapped this in a helper function and used it consistently.
Multiple Runs and Averaging
We made the script repeat each test N times (default: 3), collect results, compute averages, and display a summary at the end.
echo "📊 Read-only USB benchmark started ($RUNS run(s))"
echo "==================================="
declare -A TEST_NAMES=(
[1]="hdparm"
[2]="dd"
[3]="dd + pv"
[4]="cat + pv"
[5]="ioping"
[6]="fio"
)
declare -A TOTAL_MB
for i in {1..6}; do TOTAL_MB[$i]=0; done
CSVFILE="usb-benchmark-$(date +%Y%m%d-%H%M%S).csv"
echo "Test,Run,Speed (MB/s)" > "$CSVFILE"
for ((run=1; run<=RUNS; run++)); do
echo "▶ Run $run"
idx=1
### tests run here
echo "📄 Summary of average results for $UBUNTU_VERSION:"
echo "==================================="
SUMMARY_TABLE=""
for i in {1..6}; do
if [[ ${TOTAL_MB[$i]} != 0 ]]; then
avg=$(echo "scale=2; ${TOTAL_MB[$i]} / $RUNS" | bc)
echo "${TEST_NAMES[$i]} average: $avg MB/s"
RESULTS+=("${TEST_NAMES[$i]} average: $avg MB/s")
SUMMARY_TABLE+="${TEST_NAMES[$i]},$avg\n"
fi
done
Output Formats
To make the results user-friendly, we added:
A clean table view
CSV export for spreadsheets
Log file for later reference
if [[ "$VISUAL" == "table" || "$VISUAL" == "both" ]]; then
echo -e "📋 Table view:"
echo -e "Test Method,Average MB/s\n$SUMMARY_TABLE" | column -t -s ','
fi
if [[ "$VISUAL" == "bar" || "$VISUAL" == "both" ]]; then
if require gnuplot; then
echo -e "$SUMMARY_TABLE" | awk -F',' '{print $1" "$2}' | \
gnuplot -p -e "
set terminal dumb;
set title 'USB Read Benchmark Results ($UBUNTU_VERSION)';
set xlabel 'Test Method';
set ylabel 'MB/s';
plot '-' using 2:xtic(1) with boxes notitle
"
fi
fi
LOGFILE="usb-benchmark-$(date +%Y%m%d-%H%M%S).log"
{
echo "Benchmark for USB device: $USB_DEVICE"
echo "Mounted at: $MOUNT_PATH"
echo "Ubuntu version: $UBUNTU_VERSION"
echo "Test file: $TEST_FILE"
echo "Timestamp: $(date)"
echo "Number of runs: $RUNS"
echo ""
echo "Read speed averages:"
for line in "${RESULTS[@]}"; do
echo "$line"
done
} > "$LOGFILE"
echo "📝 Results saved to: $LOGFILE"
echo "📈 CSV exported to: $CSVFILE"
echo "==================================="
The Full Script
Here is the complete version of the script used to benchmark the read performance of a USB drive:
#!/bin/bash
# ==========================
# CONFIGURATION
# ==========================
RESULTS=()
USB_DEVICE=""
TEST_FILE=""
RUNS=1
VISUAL="none"
SUMMARY=0
# (Consider grouping related configuration into a config file or associative array if script expands)
# ==========================
# ARGUMENT PARSING
# ==========================
while [[ $# -gt 0 ]]; do
case $1 in
--device)
USB_DEVICE="$2"
shift 2
;;
--file)
TEST_FILE="$2"
shift 2
;;
--runs)
RUNS="$2"
shift 2
;;
--visual)
VISUAL="$2"
shift 2
;;
--summary)
SUMMARY=1
shift
;;
--yes|--force)
FORCE_YES=1
shift
;;
*)
echo "Unknown option: $1"
exit 1
;;
esac
done
# ==========================
# TOOL CHECK
# ==========================
ALL_TOOLS=(hdparm dd pv ioping fio lsblk stat grep awk find sort basename column gnuplot)
MISSING_TOOLS=()
require() {
if ! command -v "$1" >/dev/null; then
return 1
fi
return 0
}
check_required_tools() {
echo "🔍 Checking required tools..."
for tool in "${ALL_TOOLS[@]}"; do
if ! require "$tool"; then
MISSING_TOOLS+=("$tool")
fi
done
if [[ ${#MISSING_TOOLS[@]} -gt 0 ]]; then
echo "⚠️ The following tools are missing: ${MISSING_TOOLS[*]}"
echo "You can install them using: sudo apt install ${MISSING_TOOLS[*]}"
if [[ -z "$FORCE_YES" ]]; then
read -rp "Do you want to continue and skip tests that require them? (y/N): " yn
case $yn in
[Yy]*)
echo "Continuing with limited tests..."
;;
*)
echo "Aborting. Please install the required tools."
exit 1
;;
esac
else
echo "Continuing with limited tests (auto-confirmed)..."
fi
else
echo "✅ All required tools are available."
fi
}
# ==========================
# AUTO-DETECT USB DEVICE
# ==========================
detect_usb() {
if [[ -n "$USB_DEVICE" ]]; then
echo "📎 Using provided USB device: $USB_DEVICE"
MOUNT_PATH=$(lsblk -no MOUNTPOINT "$USB_DEVICE")
return
fi
echo "🔍 Detecting USB device..."
USB_DEVICE=""
while read -r dev tran hotplug type _; do
if [[ "$tran" == "usb" && "$hotplug" == "1" && "$type" == "disk" ]]; then
base="/dev/$dev"
part=$(lsblk -nr -o NAME,MOUNTPOINT "$base" | awk '$2 != "" {print "/dev/"$1; exit}')
if [[ -n "$part" ]]; then
USB_DEVICE="$part"
break
fi
fi
done < <(lsblk -o NAME,TRAN,HOTPLUG,TYPE,MOUNTPOINT -nr)
if [ -z "$USB_DEVICE" ]; then
echo "❌ No mounted USB partition found on any USB disk."
lsblk -o NAME,TRAN,HOTPLUG,TYPE,SIZE,MOUNTPOINT -nr | grep part
read -rp "Enter the USB device path manually (e.g., /dev/sdc1): " USB_DEVICE
fi
MOUNT_PATH=$(lsblk -no MOUNTPOINT "$USB_DEVICE")
if [ -z "$MOUNT_PATH" ]; then
echo "❌ USB device is not mounted."
exit 1
fi
echo "✅ Using USB device: $USB_DEVICE"
echo "✅ Mounted at: $MOUNT_PATH"
}
# ==========================
# FIND TEST FILE
# ==========================
find_ubuntu_iso() {
# Function to find an Ubuntu ISO on the USB device
find "$MOUNT_PATH" -type f -regextype posix-extended \
-regex ".*/ubuntu-[0-9]{2}\.[0-9]{2}-desktop-amd64\\.iso" | sort -V | tail -n1
}
find_test_file() {
if [[ -n "$TEST_FILE" ]]; then
echo "📎 Using provided test file: $(basename "$TEST_FILE")"
# Check if the provided test file is on the USB device
TEST_FILE_MOUNT_PATH=$(realpath "$TEST_FILE" | grep -oP "^$MOUNT_PATH")
if [[ -z "$TEST_FILE_MOUNT_PATH" ]]; then
echo "❌ The provided test file is not located on the USB device."
# Look for an Ubuntu ISO if it's not on the USB
TEST_FILE=$(find_ubuntu_iso)
fi
else
TEST_FILE=$(find_ubuntu_iso)
fi
if [ -z "$TEST_FILE" ]; then
echo "❌ No valid test file found."
exit 1
fi
if [[ "$TEST_FILE" =~ ubuntu-[0-9]{2}\.[0-9]{2}-desktop-amd64\.iso ]]; then
UBUNTU_VERSION=$(basename "$TEST_FILE" | grep -oP 'ubuntu-\d{2}\.\d{2}')
echo "🧪 Selected Ubuntu version: $UBUNTU_VERSION"
else
echo "📎 Selected test file: $(basename "$TEST_FILE")"
fi
}
# ==========================
# SPEED EXTRACTION
# ==========================
extract_speed() {
grep -oP '(?i)[\d.,]+\s*[KMG]i?B/s' | tail -1 | sed 's/,/./'
}
speed_to_mb() {
if [[ "$1" =~ ([0-9.,]+)[[:space:]]*([a-zA-Z/]+) ]]; then
value="${BASH_REMATCH[1]}"
unit=$(echo "${BASH_REMATCH[2]}" | tr '[:upper:]' '[:lower:]')
else
echo "0"
return
fi
case "$unit" in
kb/s) awk -v v="$value" 'BEGIN { printf "%.2f", v / 1000 }' ;;
mb/s) awk -v v="$value" 'BEGIN { printf "%.2f", v }' ;;
gb/s) awk -v v="$value" 'BEGIN { printf "%.2f", v * 1000 }' ;;
kib/s) awk -v v="$value" 'BEGIN { printf "%.2f", v / 1024 }' ;;
mib/s) awk -v v="$value" 'BEGIN { printf "%.2f", v }' ;;
gib/s) awk -v v="$value" 'BEGIN { printf "%.2f", v * 1024 }' ;;
*) echo "0" ;;
esac
}
drop_caches() {
echo "🧹 Dropping system caches..."
if [[ $EUID -ne 0 ]]; then
echo " (requires sudo)"
fi
sudo sh -c "sync && echo 3 > /proc/sys/vm/drop_caches"
}
# ==========================
# RUN BENCHMARKS
# ==========================
run_benchmarks() {
echo "📊 Read-only USB benchmark started ($RUNS run(s))"
echo "==================================="
declare -A TEST_NAMES=(
[1]="hdparm"
[2]="dd"
[3]="dd + pv"
[4]="cat + pv"
[5]="ioping"
[6]="fio"
)
declare -A TOTAL_MB
for i in {1..6}; do TOTAL_MB[$i]=0; done
CSVFILE="usb-benchmark-$(date +%Y%m%d-%H%M%S).csv"
echo "Test,Run,Speed (MB/s)" > "$CSVFILE"
for ((run=1; run<=RUNS; run++)); do
echo "▶ Run $run"
idx=1
if require hdparm; then
drop_caches
speed=$(sudo hdparm -t --direct "$USB_DEVICE" 2>/dev/null | extract_speed)
mb=$(speed_to_mb "$speed")
echo "${idx}. ${TEST_NAMES[$idx]}: $speed"
TOTAL_MB[$idx]=$(echo "${TOTAL_MB[$idx]} + $mb" | bc)
echo "${TEST_NAMES[$idx]},$run,$mb" >> "$CSVFILE"
fi
((idx++))
drop_caches
speed=$(dd if="$TEST_FILE" of=/dev/null bs=8k 2>&1 |& extract_speed)
mb=$(speed_to_mb "$speed")
echo "${idx}. ${TEST_NAMES[$idx]}: $speed"
TOTAL_MB[$idx]=$(echo "${TOTAL_MB[$idx]} + $mb" | bc)
echo "${TEST_NAMES[$idx]},$run,$mb" >> "$CSVFILE"
((idx++))
if require pv; then
drop_caches
FILESIZE=$(stat -c%s "$TEST_FILE")
speed=$(dd if="$TEST_FILE" bs=8k status=none | pv -s "$FILESIZE" -f -X 2>&1 | extract_speed)
mb=$(speed_to_mb "$speed")
echo "${idx}. ${TEST_NAMES[$idx]}: $speed"
TOTAL_MB[$idx]=$(echo "${TOTAL_MB[$idx]} + $mb" | bc)
echo "${TEST_NAMES[$idx]},$run,$mb" >> "$CSVFILE"
fi
((idx++))
if require pv; then
drop_caches
speed=$(cat "$TEST_FILE" | pv -f -X 2>&1 | extract_speed)
mb=$(speed_to_mb "$speed")
echo "${idx}. ${TEST_NAMES[$idx]}: $speed"
TOTAL_MB[$idx]=$(echo "${TOTAL_MB[$idx]} + $mb" | bc)
echo "${TEST_NAMES[$idx]},$run,$mb" >> "$CSVFILE"
fi
((idx++))
if require ioping; then
drop_caches
speed=$(ioping -c 10 -A "$USB_DEVICE" 2>/dev/null | grep 'read' | extract_speed)
mb=$(speed_to_mb "$speed")
echo "${idx}. ${TEST_NAMES[$idx]}: $speed"
TOTAL_MB[$idx]=$(echo "${TOTAL_MB[$idx]} + $mb" | bc)
echo "${TEST_NAMES[$idx]},$run,$mb" >> "$CSVFILE"
fi
((idx++))
if require fio; then
drop_caches
speed=$(fio --name=readtest --filename="$TEST_FILE" --direct=1 --rw=read --bs=8k \
--size=100M --ioengine=libaio --iodepth=16 --runtime=5s --time_based --readonly \
--minimal 2>/dev/null | awk -F';' '{print $6" KB/s"}' | extract_speed)
mb=$(speed_to_mb "$speed")
echo "${idx}. ${TEST_NAMES[$idx]}: $speed"
TOTAL_MB[$idx]=$(echo "${TOTAL_MB[$idx]} + $mb" | bc)
echo "${TEST_NAMES[$idx]},$run,$mb" >> "$CSVFILE"
fi
done
echo "📄 Summary of average results for $UBUNTU_VERSION:"
echo "==================================="
SUMMARY_TABLE=""
for i in {1..6}; do
if [[ ${TOTAL_MB[$i]} != 0 ]]; then
avg=$(echo "scale=2; ${TOTAL_MB[$i]} / $RUNS" | bc)
echo "${TEST_NAMES[$i]} average: $avg MB/s"
RESULTS+=("${TEST_NAMES[$i]} average: $avg MB/s")
SUMMARY_TABLE+="${TEST_NAMES[$i]},$avg\n"
fi
done
if [[ "$VISUAL" == "table" || "$VISUAL" == "both" ]]; then
echo -e "📋 Table view:"
echo -e "Test Method,Average MB/s\n$SUMMARY_TABLE" | column -t -s ','
fi
if [[ "$VISUAL" == "bar" || "$VISUAL" == "both" ]]; then
if require gnuplot; then
echo -e "$SUMMARY_TABLE" | awk -F',' '{print $1" "$2}' | \
gnuplot -p -e "
set terminal dumb;
set title 'USB Read Benchmark Results ($UBUNTU_VERSION)';
set xlabel 'Test Method';
set ylabel 'MB/s';
plot '-' using 2:xtic(1) with boxes notitle
"
fi
fi
LOGFILE="usb-benchmark-$(date +%Y%m%d-%H%M%S).log"
{
echo "Benchmark for USB device: $USB_DEVICE"
echo "Mounted at: $MOUNT_PATH"
echo "Ubuntu version: $UBUNTU_VERSION"
echo "Test file: $TEST_FILE"
echo "Timestamp: $(date)"
echo "Number of runs: $RUNS"
echo ""
echo "Read speed averages:"
for line in "${RESULTS[@]}"; do
echo "$line"
done
} > "$LOGFILE"
echo "📝 Results saved to: $LOGFILE"
echo "📈 CSV exported to: $CSVFILE"
echo "==================================="
}
# ==========================
# MAIN
# ==========================
check_required_tools
detect_usb
find_test_file
run_benchmarks
You van also find the latest revision of this script as a GitHub Gist.
Lessons Learned
This script has grown from a simple one-liner into a reliable tool to test USB read performance. Working with ChatGPT sped up development significantly, especially for bash edge cases and regex. But more importantly, it helped guide the evolution of the script in a structured way, with clean modular functions and consistent formatting.
Conclusion
This has been a fun and educational project. Whether you are benchmarking your own USB drives or just want to learn more about shell scripting, I hope this walkthrough is helpful.
Next up? Maybe a graphical version, or write benchmarking on a RAM disk to avoid damaging flash storage.
Stay tuned—and let me know if you use this script or improve it!
When I upgraded from an old 8GB USB stick to a shiny new 256GB one, I expected faster speeds and more convenience—especially for carrying around multiple bootable ISO files using Ventoy. With modern Linux distributions often exceeding 4GB per ISO, my old drive could barely hold a single image. But I quickly realized that storage space was only half the story—performance matters too.
Curious about how much of an upgrade I had actually made, I decided to benchmark the read speed of both USB sticks. Instead of hunting down benchmarking tools or manually comparing outputs, I turned to ChatGPT to help me craft a reliable, repeatable shell script that could automate the entire process. In this post, I’ll share how ChatGPT helped me go from an idea to a functional USB benchmark script, and what I learned along the way.
The Goal
I wanted to answer a few simple but important questions:
How much faster is my new USB stick compared to the old one?
Do different USB ports affect read speeds?
How can I automate these tests and compare the results?
But I also wanted a reusable script that would:
Detect the USB device automatically
Find or use a test file on the USB stick
Run several types of read benchmarks
Present the results clearly, with support for summary and CSV export
Getting Help from ChatGPT
I asked ChatGPT to help me write a shell script with these requirements. It guided me through:
Handling different cases for user-provided test files or Ubuntu ISOs
Parsing and converting human-readable speed outputs
Displaying results in human-friendly tables and optional CSV export
We iterated over the script, addressing edge cases like:
USB devices not mounted
Multiple USB partitions
pv not showing output unless stderr was correctly handled
Formatting output consistently across tools
ChatGPT even helped optimize the code for readability, reduce duplication, and handle both space-separated and non-space-separated speed values like “18.6 MB/s” and “18.6MB/s”.
Benchmark Results
With the script ready, I ran tests on three configurations:
The old USB stick is not only limited in capacity but also very slow. It barely breaks 20 MB/s in most tests.
The new USB stick, when plugged into a fast USB 3.0 port, is significantly faster—over 10x the speed in most benchmarks.
Plugging the same new stick into a slower port dramatically reduces its performance—a good reminder to check where you plug it in.
Tools like hdparm, dd, and cat + pv give relatively consistent results. However, ioping and fio behave differently due to the way they access data—random access or block size differences can impact results.
Also worth noting: the metal casing of the new USB stick gets warm after a few test runs, unlike the old plastic one.
Conclusion
Using ChatGPT to develop this benchmark script was like pair-programming with an always-available assistant. It accelerated development, helped troubleshoot weird edge cases, and made the script more polished than if I had done it alone.
If you want to test your own USB drives—or ensure you’re using the best port for speed—this benchmark script is a great tool to have in your kit. And if you’re looking to learn shell scripting, pairing with ChatGPT is an excellent way to level up.
Want the script? I’ll share the full version of the script and instructions on how to use it in a follow-up post. Stay tuned!
