Master Nginx Performance: 20+ Proven Optimization Techniques

Nginx Process and Worker Settings

Set the Nginx worker process to run as a non‑root user and match the number of CPU cores. Use worker_processes auto; and worker_cpu_affinity auto; to bind workers to specific CPUs, reducing context switches.

# Example worker configuration
user nginx;
worker_processes auto;
worker_cpu_affinity auto;
worker_rlimit_nofile 65535;

Event Model and Connection Limits

Enable the epoll event model and configure the maximum connections per worker. Adjust worker_connections based on system file descriptor limits.

events {
    use epoll;
    worker_connections 10240;
    accept_mutex on;
}

HTTP Core Optimizations

Enable efficient file transmission with sendfile on; and tcp_nopush on;. Configure keep‑alive timeouts, client body size limits, and disable server version disclosure.

http {
    include mime.types;
    default_type application/octet-stream;
    sendfile on;
    tcp_nopush on;
    keepalive_timeout 65;
    client_max_body_size 200m;
    server_tokens off;
}

Gzip Compression

Compress text responses to save bandwidth. Set minimum length, compression level, and MIME types.

gzip on;
 gzip_min_length 1k;
 gzip_buffers 4 32k;
 gzip_comp_level 6;
 gzip_types text/plain text/css application/javascript application/xml;

FastCGI Tuning and Caching

Configure FastCGI timeouts, buffer sizes, and enable persistent connections with fastcgi_keep_conn on;. Set up FastCGI cache paths and validity periods.

fastcgi_connect_timeout 240;
fastcgi_send_timeout 240;
fastcgi_read_timeout 240;
fastcgi_buffer_size 64k;
fastcgi_cache_path /data/ngx_fcgi_cache levels=2:2 keys_zone=cache_fastcgi:128m inactive=1d max_size=10g;
fastcgi_cache cache_fastcgi;
fastcgi_cache_valid 200 302 1h;
fastcgi_cache_valid 301 1d;
fastcgi_cache_valid any 1m;

Expires Headers and Caching Static Assets

Set long expiration times for static resources to reduce repeat downloads.

location ~* \.(ico|jpe?g|png|gif|css|js)$ {
    expires 30d;
    access_log off;
    log_not_found off;
}

Anti‑Hotlink Configuration

Prevent other sites from directly linking to your media files using valid_referers and returning a 403 status for invalid requests.

location ~* \.(gif|jpg|png)$ {
    valid_referers none blocked *.example.com;
    if ($invalid_referer) { return 403; }
}

Kernel and System Parameter Optimizations

Adjust Linux kernel settings to improve network performance and increase the maximum number of open files.

# /etc/sysctl.conf examples
net.ipv4.tcp_syncookies = 1
net.core.somaxconn = 1024
net.ipv4.tcp_tw_reuse = 1
net.ipv4.tcp_fin_timeout = 10

Update /etc/security/limits.conf to raise nofile limits for all users and the Nginx user.

* soft nofile 65535
* hard nofile 65535

Common Pitfalls and Troubleshooting

Address issues such as character set problems, directory listings, and proper use of location modifiers. Use autoindex off; to hide directory indexes and set charset utf-8; where needed.