Performance Optimization

CPU Optimization

Nginx Worker Optimization

# /etc/nginx/nginx.conf
# Set workers to CPU core count
worker_processes auto;

# Optimize worker connections
events {
    worker_connections 1024;
    use epoll;
}

# Enable multi-threading
worker_rlimit_nofile 65535;

Memory Optimization

Enable Swap (with caution)

# Create 2GB swap file
fallocate -l 2G /swapfile
chmod 600 /swapfile
mkswap /swapfile
swapon /swapfile

# Make permanent
echo '/swapfile none swap sw 0 0' >> /etc/fstab

# Optimize swap usage (lower swappiness)
sysctl vm.swappiness=10
echo 'vm.swappiness=10' >> /etc/sysctl.conf

MySQL Memory Tuning

# /etc/mysql/my.cnf
[mysqld]
# For 2GB RAM instance
innodb_buffer_pool_size = 1G
key_buffer_size = 256M
max_connections = 150
query_cache_size = 64M

Disk I/O Optimization

Enable noatime

# Edit /etc/fstab
# Change 'defaults' to 'defaults,noatime'
UUID=xxx / ext4 defaults,noatime 0 1

# Remount
mount -o remount /

Network Optimization

TCP Tuning

# /etc/sysctl.conf
# Increase TCP buffer sizes
net.core.rmem_max = 16777216
net.core.wmem_max = 16777216
net.ipv4.tcp_rmem = 4096 87380 16777216
net.ipv4.tcp_wmem = 4096 65536 16777216

# Enable TCP window scaling
net.ipv4.tcp_window_scaling = 1

# Increase connection backlog
net.core.somaxconn = 65535

# Apply changes
sysctl -p

Enable HTTP/2 and Compression

# Nginx configuration
server {
    listen 443 ssl http2;
    
    # Enable gzip compression
    gzip on;
    gzip_vary on;
    gzip_min_length 1024;
    gzip_types text/plain text/css text/xml text/javascript 
               application/x-javascript application/xml+rss 
               application/json application/javascript;
}

Caching Strategies

Web Server Caching

# Nginx static file caching
location ~* \.(jpg|jpeg|png|gif|ico|css|js|svg|woff|woff2)$ {
    expires 30d;
    add_header Cache-Control "public, immutable";
}

Redis Setup

# Install Redis
apt install redis-server

# Configure Redis memory limit
# /etc/redis/redis.conf
maxmemory 256mb
maxmemory-policy allkeys-lru

systemctl restart redis-server

OPcache for PHP

# /etc/php/*/fpm/php.ini
opcache.enable=1
opcache.memory_consumption=128
opcache.interned_strings_buffer=8
opcache.max_accelerated_files=10000
opcache.revalidate_freq=60

Database Optimization

Index Optimization

# Find slow queries (MySQL)
SET GLOBAL slow_query_log = 'ON';
SET GLOBAL long_query_time = 1;

# Analyze slow queries
mysqldumpslow /var/log/mysql/mysql-slow.log

# Add indexes to frequently queried columns
CREATE INDEX idx_user_email ON users(email);
CREATE INDEX idx_posts_created ON posts(created_at);

Query Optimization Tips

• Use EXPLAIN to analyze queries
• Avoid SELECT * - specify needed columns
• Use LIMIT for pagination
• Cache frequent queries

CDN Integration

Offload static content to a CDN for better global performance:

Quick Wins Checklist