Optimize PHP-FPM performance with memory tuning and connection pooling for high-traffic websites

#!/usr/bin/env bash

set -euo pipefail

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

# Global variables
PHP_VERSION=""
PHP_INI_PATH=""
PHP_FPM_POOL_PATH=""
PHP_FPM_SERVICE=""
WEB_USER=""
WEB_GROUP=""
SOCKET_PATH=""

# Cleanup function
cleanup() {
    echo -e "${RED}Installation failed. Check logs above for details.${NC}"
    exit 1
}

trap cleanup ERR

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

# Auto-detect distribution
if [ -f /etc/os-release ]; then
    . /etc/os-release
    case "$ID" in
        ubuntu|debian) 
            PKG_MGR="apt"
            PKG_INSTALL="apt install -y"
            PKG_UPDATE="apt update && apt upgrade -y"
            PHP_VERSION="8.3"
            PHP_INI_PATH="/etc/php/8.3/fpm/php.ini"
            PHP_FPM_POOL_PATH="/etc/php/8.3/fpm/pool.d/www.conf"
            PHP_FPM_SERVICE="php8.3-fpm"
            WEB_USER="www-data"
            WEB_GROUP="www-data"
            SOCKET_PATH="/run/php/php8.3-fpm.sock"
            ;;
        almalinux|rocky|centos|rhel|ol|fedora) 
            PKG_MGR="dnf"
            PKG_INSTALL="dnf install -y"
            PKG_UPDATE="dnf update -y"
            PHP_VERSION=""
            PHP_INI_PATH="/etc/php.ini"
            PHP_FPM_POOL_PATH="/etc/php-fpm.d/www.conf"
            PHP_FPM_SERVICE="php-fpm"
            WEB_USER="nginx"
            WEB_GROUP="nginx"
            SOCKET_PATH="/run/php-fpm/www.sock"
            ;;
        amzn) 
            PKG_MGR="yum"
            PKG_INSTALL="yum install -y"
            PKG_UPDATE="yum update -y"
            PHP_VERSION=""
            PHP_INI_PATH="/etc/php.ini"
            PHP_FPM_POOL_PATH="/etc/php-fpm.d/www.conf"
            PHP_FPM_SERVICE="php-fpm"
            WEB_USER="nginx"
            WEB_GROUP="nginx"
            SOCKET_PATH="/run/php-fpm/www.sock"
            ;;
        *) 
            echo -e "${RED}Unsupported distro: $ID${NC}"
            exit 1
            ;;
    esac
else
    echo -e "${RED}Cannot detect OS distribution${NC}"
    exit 1
fi

echo -e "${GREEN}Starting PHP-FPM optimization for $PRETTY_NAME${NC}"

# Step 1: Update system packages
echo -e "${GREEN}[1/7] Updating system packages...${NC}"
$PKG_UPDATE

# Step 2: Install PHP-FPM and extensions
echo -e "${GREEN}[2/7] Installing PHP-FPM and extensions...${NC}"
case "$ID" in
    ubuntu|debian)
        $PKG_INSTALL php${PHP_VERSION}-fpm php${PHP_VERSION}-opcache php${PHP_VERSION}-mysql php${PHP_VERSION}-curl php${PHP_VERSION}-gd php${PHP_VERSION}-mbstring php${PHP_VERSION}-xml php${PHP_VERSION}-zip
        ;;
    *)
        $PKG_INSTALL php-fpm php-opcache php-mysqlnd php-curl php-gd php-mbstring php-xml php-zip
        ;;
esac

# Step 3: Configure PHP memory limits and execution settings
echo -e "${GREEN}[3/7] Configuring PHP memory limits and execution settings...${NC}"
cp "$PHP_INI_PATH" "$PHP_INI_PATH.backup"

cat >> "$PHP_INI_PATH" << 'EOF'

; Optimized memory and execution settings
memory_limit = 256M
max_execution_time = 60
max_input_time = 60
post_max_size = 64M
upload_max_filesize = 32M
max_file_uploads = 20
date.timezone = UTC
EOF

# Step 4: Enable and optimize OpCache
echo -e "${GREEN}[4/7] Configuring OpCache for bytecode caching...${NC}"
cat >> "$PHP_INI_PATH" << 'EOF'

; OpCache optimization settings
opcache.enable=1
opcache.memory_consumption=256
opcache.interned_strings_buffer=16
opcache.max_accelerated_files=10000
opcache.revalidate_freq=2
opcache.save_comments=1
opcache.enable_file_override=1
EOF

# Step 5: Configure PHP-FPM process pool settings
echo -e "${GREEN}[5/7] Configuring PHP-FPM process pool settings...${NC}"
cp "$PHP_FPM_POOL_PATH" "$PHP_FPM_POOL_PATH.backup"

cat > "$PHP_FPM_POOL_PATH" << EOF
[www]
user = $WEB_USER
group = $WEB_GROUP
listen = $SOCKET_PATH
listen.owner = $WEB_USER
listen.group = $WEB_GROUP
listen.mode = 0660

pm = dynamic
pm.max_children = 50
pm.start_servers = 5
pm.min_spare_servers = 5
pm.max_spare_servers = 15
pm.max_requests = 1000

request_terminate_timeout = 120
rlimit_files = 4096
rlimit_core = 0

catch_workers_output = yes
decorate_workers_output = no
clear_env = no

env[HOSTNAME] = \$HOSTNAME
env[PATH] = /usr/local/bin:/usr/bin:/bin
env[TMP] = /tmp
env[TMPDIR] = /tmp
env[TEMP] = /tmp
EOF

# Step 6: Configure global PHP-FPM settings
echo -e "${GREEN}[6/7] Configuring global PHP-FPM settings...${NC}"
case "$ID" in
    ubuntu|debian)
        FPM_CONF="/etc/php/8.3/fpm/php-fpm.conf"
        ;;
    *)
        FPM_CONF="/etc/php-fpm.conf"
        ;;
esac

if [ -f "$FPM_CONF" ]; then
    cp "$FPM_CONF" "$FPM_CONF.backup"
    
    # Set global parameters
    sed -i 's/^;emergency_restart_threshold.*/emergency_restart_threshold = 10/' "$FPM_CONF"
    sed -i 's/^;emergency_restart_interval.*/emergency_restart_interval = 1m/' "$FPM_CONF"
    sed -i 's/^;process_control_timeout.*/process_control_timeout = 10s/' "$FPM_CONF"
fi

# Create necessary directories and set permissions
mkdir -p $(dirname "$SOCKET_PATH")
chown -R $WEB_USER:$WEB_GROUP $(dirname "$SOCKET_PATH")

# Step 7: Start and enable PHP-FPM service
echo -e "${GREEN}[7/7] Starting and enabling PHP-FPM service...${NC}"
systemctl enable $PHP_FPM_SERVICE
systemctl restart $PHP_FPM_SERVICE

# Verification checks
echo -e "${GREEN}Performing verification checks...${NC}"

# Check if PHP-FPM is running
if systemctl is-active --quiet $PHP_FPM_SERVICE; then
    echo -e "${GREEN}✓ PHP-FPM service is running${NC}"
else
    echo -e "${RED}✗ PHP-FPM service failed to start${NC}"
    systemctl status $PHP_FPM_SERVICE
    exit 1
fi

# Check if socket exists
if [ -S "$SOCKET_PATH" ]; then
    echo -e "${GREEN}✓ PHP-FPM socket created successfully${NC}"
else
    echo -e "${RED}✗ PHP-FPM socket not found${NC}"
    exit 1
fi

# Check PHP configuration
php --version > /dev/null 2>&1 && echo -e "${GREEN}✓ PHP is working correctly${NC}" || echo -e "${RED}✗ PHP configuration error${NC}"

# Check OpCache status
php -m | grep -q "Zend OPcache" && echo -e "${GREEN}✓ OpCache is enabled${NC}" || echo -e "${YELLOW}⚠ OpCache not detected${NC}"

echo -e "${GREEN}PHP-FPM optimization completed successfully!${NC}"
echo -e "${YELLOW}Configuration summary:${NC}"
echo "- PHP-FPM service: $PHP_FPM_SERVICE"
echo "- Socket path: $SOCKET_PATH"
echo "- Process pool: Dynamic (5-50 workers)"
echo "- Memory limit: 256M per process"
echo "- OpCache: 256M allocated"
echo "- Max requests per worker: 1000"
echo ""
echo -e "${YELLOW}Next steps:${NC}"
echo "1. Configure your web server (Nginx/Apache) to use PHP-FPM"
echo "2. Monitor performance with: systemctl status $PHP_FPM_SERVICE"
echo "3. Adjust pm.max_children based on your server's RAM"
echo "4. Review logs: journalctl -u $PHP_FPM_SERVICE"