Benchmark and optimize Linux disk I/O performance with fio testing

#!/usr/bin/env bash

set -euo pipefail

# Colors for output
RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[1;33m'
NC='\033[0m'

# Global variables
TEST_DIR="/tmp/fio-test"
RESULTS_DIR="/tmp/fio-results"
COMPREHENSIVE_JOB_FILE="$TEST_DIR/comprehensive-test.fio"

# Print colored output
print_status() {
    local color=$1
    local message=$2
    echo -e "${color}${message}${NC}"
}

# Usage message
usage() {
    echo "Usage: $0 [OPTIONS]"
    echo "Options:"
    echo "  -d, --test-dir DIR    Test directory (default: /tmp/fio-test)"
    echo "  -r, --results-dir DIR Results directory (default: /tmp/fio-results)"
    echo "  -h, --help           Show this help message"
    exit 1
}

# Parse command line arguments
while [[ $# -gt 0 ]]; do
    case $1 in
        -d|--test-dir)
            TEST_DIR="$2"
            shift 2
            ;;
        -r|--results-dir)
            RESULTS_DIR="$2"
            shift 2
            ;;
        -h|--help)
            usage
            ;;
        *)
            print_status "$RED" "Unknown option: $1"
            usage
            ;;
    esac
done

# Cleanup function for error handling
cleanup() {
    print_status "$YELLOW" "Cleaning up temporary files..."
    rm -rf "$TEST_DIR" 2>/dev/null || true
}

# Set up error trap
trap cleanup ERR

# Check if running as root or with sudo
check_privileges() {
    if [[ $EUID -ne 0 ]]; then
        print_status "$RED" "This script must be run as root or with sudo"
        exit 1
    fi
}

# Detect distribution and package manager
detect_distro() {
    print_status "$YELLOW" "[1/8] Detecting Linux distribution..."
    
    if [ -f /etc/os-release ]; then
        . /etc/os-release
        case "$ID" in
            ubuntu|debian)
                PKG_MGR="apt"
                PKG_INSTALL="apt install -y"
                UPDATE_CMD="apt update && apt upgrade -y"
                ;;
            almalinux|rocky|centos|rhel|ol|fedora)
                PKG_MGR="dnf"
                PKG_INSTALL="dnf install -y"
                UPDATE_CMD="dnf update -y"
                ;;
            amzn)
                PKG_MGR="yum"
                PKG_INSTALL="yum install -y"
                UPDATE_CMD="yum update -y"
                ;;
            *)
                print_status "$RED" "Unsupported distribution: $ID"
                exit 1
                ;;
        esac
        print_status "$GREEN" "Detected: $PRETTY_NAME (Package manager: $PKG_MGR)"
    else
        print_status "$RED" "Cannot detect Linux distribution"
        exit 1
    fi
}

# Update system packages
update_system() {
    print_status "$YELLOW" "[2/8] Updating system packages..."
    eval "$UPDATE_CMD"
    print_status "$GREEN" "System packages updated successfully"
}

# Install fio and related tools
install_fio() {
    print_status "$YELLOW" "[3/8] Installing fio and related tools..."
    $PKG_INSTALL fio iotop hdparm
    print_status "$GREEN" "fio and related tools installed successfully"
}

# Verify fio installation
verify_installation() {
    print_status "$YELLOW" "[4/8] Verifying fio installation..."
    
    if ! command -v fio &> /dev/null; then
        print_status "$RED" "fio installation failed"
        exit 1
    fi
    
    local fio_version=$(fio --version 2>/dev/null || echo "unknown")
    local fio_path=$(which fio)
    
    print_status "$GREEN" "fio installed successfully:"
    echo "  Version: $fio_version"
    echo "  Path: $fio_path"
}

# Create test directories
setup_test_environment() {
    print_status "$YELLOW" "[5/8] Setting up test environment..."
    
    # Create test and results directories
    mkdir -p "$TEST_DIR"
    mkdir -p "$RESULTS_DIR"
    
    # Set proper permissions
    chmod 755 "$TEST_DIR"
    chmod 755 "$RESULTS_DIR"
    
    print_status "$GREEN" "Test environment created:"
    echo "  Test directory: $TEST_DIR"
    echo "  Results directory: $RESULTS_DIR"
}

# Create comprehensive benchmark job file
create_job_file() {
    print_status "$YELLOW" "[6/8] Creating comprehensive benchmark job file..."
    
    cat > "$COMPREHENSIVE_JOB_FILE" << 'EOF'
[global]
ioengine=libaio
direct=1
size=1G
runtime=30
time_based=1
group_reporting=1

[seq-read]
rw=read
bs=1M
numjobs=1
stonewall

[seq-write]
rw=write
bs=1M
numjobs=1
fsync=1
stonewall

[rand-read-4k]
rw=randread
bs=4k
numjobs=4
iodepth=32
stonewall

[rand-write-4k]
rw=randwrite
bs=4k
numjobs=4
iodepth=32
fsync=1
stonewall

[mixed-workload]
rw=randrw
rwmixread=70
bs=4k
numjobs=4
iodepth=16
stonewall
EOF

    chmod 644 "$COMPREHENSIVE_JOB_FILE"
    print_status "$GREEN" "Comprehensive benchmark job file created: $COMPREHENSIVE_JOB_FILE"
}

# Run basic performance tests
run_basic_tests() {
    print_status "$YELLOW" "[7/8] Running basic disk performance tests..."
    
    cd "$TEST_DIR"
    
    print_status "$YELLOW" "Running sequential read test..."
    fio --name=sequential-read --ioengine=libaio --rw=read --bs=1M --size=1G \
        --numjobs=1 --time_based --runtime=30 --group_reporting \
        > "$RESULTS_DIR/sequential-read.txt" 2>&1
    
    print_status "$YELLOW" "Running sequential write test..."
    fio --name=sequential-write --ioengine=libaio --rw=write --bs=1M --size=1G \
        --numjobs=1 --time_based --runtime=30 --group_reporting --fsync=1 \
        > "$RESULTS_DIR/sequential-write.txt" 2>&1
    
    print_status "$YELLOW" "Running random read test..."
    fio --name=random-read --ioengine=libaio --rw=randread --bs=4k --size=1G \
        --numjobs=4 --time_based --runtime=30 --group_reporting --iodepth=32 \
        > "$RESULTS_DIR/random-read.txt" 2>&1
    
    print_status "$YELLOW" "Running random write test..."
    fio --name=random-write --ioengine=libaio --rw=randwrite --bs=4k --size=1G \
        --numjobs=4 --time_based --runtime=30 --group_reporting --iodepth=32 --fsync=1 \
        > "$RESULTS_DIR/random-write.txt" 2>&1
    
    print_status "$GREEN" "Basic performance tests completed"
}

# Run comprehensive benchmark suite
run_comprehensive_tests() {
    print_status "$YELLOW" "[8/8] Running comprehensive benchmark suite..."
    
    cd "$TEST_DIR"
    
    # Run comprehensive test with text output
    fio "$COMPREHENSIVE_JOB_FILE" --output="$RESULTS_DIR/comprehensive-results.txt" 2>&1
    
    # Run comprehensive test with JSON output
    fio "$COMPREHENSIVE_JOB_FILE" --output-format=json --output="$RESULTS_DIR/comprehensive-results.json" 2>&1
    
    # Set proper permissions for results
    chmod 644 "$RESULTS_DIR"/*.txt "$RESULTS_DIR"/*.json
    
    print_status "$GREEN" "Comprehensive benchmark suite completed"
}

# Verify results and display summary
verify_results() {
    print_status "$YELLOW" "Verifying benchmark results..."
    
    local results_count=$(find "$RESULTS_DIR" -name "*.txt" -o -name "*.json" | wc -l)
    
    if [[ $results_count -gt 0 ]]; then
        print_status "$GREEN" "✓ Benchmark results generated successfully"
        echo ""
        print_status "$GREEN" "Results location: $RESULTS_DIR"
        echo "Available result files:"
        ls -la "$RESULTS_DIR"
        echo ""
        print_status "$YELLOW" "Next steps:"
        echo "1. Review results in: $RESULTS_DIR"
        echo "2. Analyze performance bottlenecks"
        echo "3. Run specific device tests if needed (see fio documentation)"
        echo "4. Clean up test files when done: rm -rf $TEST_DIR"
    else
        print_status "$RED" "✗ No benchmark results found"
        exit 1
    fi
}

# Main execution
main() {
    print_status "$GREEN" "=== FIO Disk Performance Benchmarking Setup ==="
    
    check_privileges
    detect_distro
    update_system
    install_fio
    verify_installation
    setup_test_environment
    create_job_file
    run_basic_tests
    run_comprehensive_tests
    verify_results
    
    print_status "$GREEN" "=== FIO installation and benchmarking completed successfully ==="
}

# Execute main function
main "$@"