How to Tune Nginx for Over 900k Requests per Second on Linux

Part 2: Using Nginx for High‑Performance Servers

This article is the second part of the series "Building a 3‑Million‑Requests‑Per‑Second High‑Performance Server Cluster". It demonstrates how to configure any web server, choosing Nginx for its lightweight, reliable, and high‑performance characteristics.

A well‑tuned Nginx on Linux can normally handle 500‑600k requests per second; the configuration shown here consistently reaches 904k requests per second and remains stable under a 12‑hour load test.

Installation and Basic Setup

Install Nginx from the EPEL repository: yum -y install nginx Backup the original configuration and edit it as needed:

cp /etc/nginx/nginx.conf /etc/nginx/nginx.conf.orig

vim /etc/nginx/nginx.conf

Key Nginx Performance Directives

Insert the following settings into nginx.conf (adjust values to match your hardware): worker_processes 24; worker_rlimit_nofile 200000; error_log /var/log/nginx/error.log crit; worker_connections 4000; use epoll; multi_accept on; open_file_cache max=200000 inactive=20s; open_file_cache_valid 30s; open_file_cache_min_uses 2; open_file_cache_errors on; access_log off; sendfile on; tcp_nopush on; tcp_nodelay on; keepalive_timeout 30; keepalive_requests 100000; reset_timedout_connection on; client_body_timeout 10; send_timeout 2; gzip on; gzip_min_length 10240; gzip_proxied expired no-cache no-store private auth; gzip_types text/plain text/css text/xml application/javascript application/x-javascript; gzip_disable "MSIE [1-6].";

Start Nginx and enable it at boot:

service nginx start

chkconfig nginx on

Load Testing with Tsung

Configure Tsung (edit ~/.tsung/tsung.xml) to point to your web server and start the test: tsung start After the test finishes (about 10 minutes for a peak measurement), press Ctrl+C and view the report with the previously defined alias treport.

Web Server Tuning – Part 2: TCP Stack Optimization

The following kernel TCP settings improve network bandwidth for any web server. On a 10‑Gbps NIC they raised throughput from 8 Gbps to 9.3 Gbps.

Install Benchmark Tools

yum -y install netperf iperf

Modify sysctl Parameters

Edit /etc/sysctl.conf and add:

# Increase local port range
net.ipv4.ip_local_port_range = 2000 65000
# Enable TCP window scaling
net.ipv4.tcp_window_scaling = 1
# Increase SYN backlog
net.ipv4.tcp_max_syn_backlog = 3240000
# Increase listen backlog
net.core.somaxconn = 3240000
# Increase TIME_WAIT buckets
net.ipv4.tcp_max_tw_buckets = 1440000
# Increase socket buffers
net.core.rmem_default = 8388608
net.core.rmem_max = 16777216
net.core.wmem_max = 16777216
net.ipv4.tcp_rmem = 4096 87380 16777216
net.ipv4.tcp_wmem = 4096 65536 16777216
# Use cubic congestion control
net.ipv4.tcp_congestion_control = cubic

Apply the changes: sysctl -p /etc/sysctl.conf After each change, run a network benchmark (netperf, iperf, or a custom script) to measure its impact.