Performance Optimization Guide

Maximizing server and application performance is crucial for delivering excellent user experiences and efficiently utilizing resources.

System-Level Optimization

CPU Optimization

Optimize CPU performance through:

Process Priority Management

# View process priorities
ps -eo pid,ppid,ni,comm

# Adjust process priority
nice -n -10 important_process
renice -10 -p process_id

CPU Affinity

# Set CPU affinity for a process
taskset -c 0,1 process_name
taskset -pc 0,1 process_id

# View current affinity
taskset -p process_id

Memory Optimization

Virtual Memory Tuning

# Optimize swappiness
echo 'vm.swappiness=10' >> /etc/sysctl.conf

# Adjust dirty ratios
echo 'vm.dirty_ratio=15' >> /etc/sysctl.conf
echo 'vm.dirty_background_ratio=5' >> /etc/sysctl.conf

# Apply changes
sysctl -p

Memory Monitoring

# Monitor memory usage
free -h
vmstat 1 10
sar -r 1 10

# Check for memory leaks
valgrind --leak-check=full ./your_program

Storage Optimization

I/O Scheduler Optimization

# Check current I/O scheduler
cat /sys/block/sda/queue/scheduler

# Set appropriate scheduler
echo deadline > /sys/block/sda/queue/scheduler  # For HDDs
echo noop > /sys/block/sda/queue/scheduler      # For SSDs

File System Tuning

# Mount options for performance
mount -o noatime,nodiratime /dev/sda1 /mount/point

# XFS tuning
mount -o noatime,largeio,inode64,swalloc /dev/sda1 /mount/point

# ext4 tuning
tune2fs -o journal_data_writeback /dev/sda1

Web Server Optimization

Nginx Performance Tuning

Basic Configuration

worker_processes auto;
worker_cpu_affinity auto;
worker_connections 1024;

# Enable gzip compression
gzip on;
gzip_vary on;
gzip_min_length 1024;
gzip_types text/plain text/css application/json application/javascript text/xml application/xml;

# Enable HTTP/2
listen 443 ssl http2;

# Optimize buffers
client_body_buffer_size 10K;
client_header_buffer_size 1k;
client_max_body_size 8m;
large_client_header_buffers 4 4k;

Caching Configuration

# Browser caching
location ~* \.(jpg|jpeg|png|gif|ico|css|js)$ {
    expires 1y;
    add_header Cache-Control "public, immutable";
}

# Proxy caching
proxy_cache_path /var/cache/nginx levels=1:2 keys_zone=app_cache:10m max_size=10g;

location / {
    proxy_cache app_cache;
    proxy_cache_valid 200 1h;
    proxy_cache_use_stale error timeout updating;
}

Apache Performance Tuning

MPM Configuration

# For high-traffic sites (Event MPM)
<IfModule mpm_event_module>
    StartServers 3
    MinSpareThreads 75
    MaxSpareThreads 250
    ThreadsPerChild 25
    MaxRequestWorkers 400
    MaxConnectionsPerChild 1000
</IfModule>

Module Optimization

# Enable compression
LoadModule deflate_module modules/mod_deflate.so
<Location />
    SetOutputFilter DEFLATE
    SetEnvIfNoCase Request_URI "\.(?:gif|jpe?g|png)$" no-gzip dont-vary
</Location>

# Enable caching
LoadModule expires_module modules/mod_expires.so
ExpiresActive On
ExpiresByType image/jpg "access plus 1 month"
ExpiresByType image/jpeg "access plus 1 month"
ExpiresByType image/gif "access plus 1 month"
ExpiresByType image/png "access plus 1 month"
ExpiresByType text/css "access plus 1 month"
ExpiresByType application/pdf "access plus 1 month"
ExpiresByType text/javascript "access plus 1 month"
ExpiresByType application/javascript "access plus 1 month"

Database Optimization

MySQL/MariaDB Tuning

Configuration Optimization

[mysqld]
# Buffer pool size (75% of available RAM)
innodb_buffer_pool_size = 6G
innodb_buffer_pool_instances = 6

# Log file optimization
innodb_log_file_size = 1G
innodb_log_buffer_size = 16M

# Connection optimization
max_connections = 500
max_connect_errors = 10000

# Query cache
query_cache_size = 256M
query_cache_type = 1

# Thread optimization
thread_cache_size = 50
table_open_cache = 4000

Query Optimization

-- Use EXPLAIN to analyze queries
EXPLAIN SELECT * FROM users WHERE email = 'user@example.com';

-- Create appropriate indexes
CREATE INDEX idx_users_email ON users(email);
CREATE INDEX idx_orders_user_date ON orders(user_id, created_at);

-- Optimize slow queries
SELECT * FROM mysql.slow_log WHERE query_time > 2;

PostgreSQL Tuning

Configuration Optimization

# Memory settings
shared_buffers = 2GB
effective_cache_size = 6GB
work_mem = 64MB
maintenance_work_mem = 512MB

# Write-ahead log
wal_buffers = 16MB
checkpoint_completion_target = 0.7
wal_writer_delay = 200ms

# Connection settings
max_connections = 200

Application-Level Optimization

PHP Performance

OPcache Configuration

; Enable OPcache
opcache.enable=1
opcache.memory_consumption=256
opcache.interned_strings_buffer=8
opcache.max_accelerated_files=4000
opcache.revalidate_freq=60
opcache.fast_shutdown=1

PHP-FPM Tuning

[www]
pm = dynamic
pm.max_children = 50
pm.start_servers = 5
pm.min_spare_servers = 5
pm.max_spare_servers = 35
pm.max_requests = 1000

; Process manager settings
pm.status_path = /status
ping.path = /ping

Node.js Performance

Cluster Mode

const cluster = require('cluster');
const numCPUs = require('os').cpus().length;

if (cluster.isMaster) {
  for (let i = 0; i < numCPUs; i++) {
    cluster.fork();
  }
  
  cluster.on('exit', (worker) => {
    console.log(`Worker ${worker.process.pid} died`);
    cluster.fork();
  });
} else {
  require('./app.js');
}

Memory Management

// Garbage collection optimization
node --max-old-space-size=4096 app.js

// Memory leak detection
const memwatch = require('memwatch-next');
memwatch.on('leak', (info) => {
  console.error('Memory leak detected:', info);
});

Network Optimization

TCP Tuning

Kernel Parameters

# Increase network buffers
echo 'net.core.rmem_max = 16777216' >> /etc/sysctl.conf
echo 'net.core.wmem_max = 16777216' >> /etc/sysctl.conf
echo 'net.ipv4.tcp_rmem = 4096 16384 16777216' >> /etc/sysctl.conf
echo 'net.ipv4.tcp_wmem = 4096 16384 16777216' >> /etc/sysctl.conf

# TCP congestion control
echo 'net.ipv4.tcp_congestion_control = bbr' >> /etc/sysctl.conf

# Connection tracking
echo 'net.netfilter.nf_conntrack_max = 1000000' >> /etc/sysctl.conf

CDN Implementation

Cloudflare Configuration

// Next.js with Cloudflare optimization
const nextConfig = {
  async headers() {
    return [
      {
        source: '/(.*)',
        headers: [
          {
            key: 'Cache-Control',
            value: 'public, max-age=31536000, immutable',
          },
        ],
      },
    ];
  },
};

Monitoring and Profiling

Performance Monitoring Tools

System Monitoring

# Real-time monitoring
htop
iotop
nethogs

# Historical monitoring
sar -u 1 60    # CPU usage
sar -r 1 60    # Memory usage
sar -d 1 60    # Disk I/O

Application Profiling

# PHP profiling with Xdebug
php -dxdebug.profiler_enable=1 -dxdebug.profiler_output_dir=/tmp script.php

# Node.js profiling
node --prof app.js
node --prof-process isolate-*.log > processed.txt

Performance Benchmarking

Web Server Benchmarking

# Apache Bench
ab -n 10000 -c 100 http://example.com/

# Siege
siege -c 100 -t 60s http://example.com/

# wrk
wrk -t12 -c400 -d30s http://example.com/

Database Benchmarking

# MySQL benchmark
sysbench oltp_read_write --table-size=1000000 --mysql-db=test --mysql-user=root prepare
sysbench oltp_read_write --table-size=1000000 --mysql-db=test --mysql-user=root --threads=16 run

Optimization Checklist

Server Optimization

• Configure appropriate swappiness
• Optimize I/O scheduler
• Tune TCP parameters
• Enable compression
• Configure caching

Application Optimization

• Enable OPcache/bytecode caching
• Optimize database queries
• Implement connection pooling
• Use CDN for static assets
• Minify CSS/JS files

Monitoring Setup

• Set up performance monitoring
• Configure alerting
• Regular performance testing
• Capacity planning

Remember: Performance optimization is an iterative process. Monitor, test, optimize, and repeat to achieve the best results.