Hands‑on Nginx High‑Concurrency Tuning: Boost Performance Up to 10×

Nginx is a core component of large‑scale architectures, and achieving high concurrency requires careful configuration.

worker_processes controls how many worker processes Nginx spawns. The article shows a basic setting worker_processes 4;, then recommends using worker_processes auto; so each CPU core gets a dedicated worker, illustrated with an 8‑core server example.

worker_connections defines the maximum number of connections each worker can handle. An example configuration sets worker_connections 10240;, yielding a theoretical maximum of 8 × 10240 = 81920 concurrent connections.

The default Linux file‑descriptor limit ( ulimit -n) is 1024, which is far too low for high‑traffic Nginx. The guide advises editing /etc/security/limits.conf to increase both soft and hard limits to 65535 using lines like * soft nofile 65535 and * hard nofile 65535.

sendfile zero‑copy is explained as a way to avoid multiple data copies between user space and kernel space. By enabling sendfile on;, Nginx can transfer data directly from disk to the network interface, reducing CPU usage and copy operations. This optimization is especially beneficial for serving static assets such as images, videos, and other files.

Applying these configurations—auto‑scaled workers, high worker_connections, elevated file‑descriptor limits, and sendfile—provides a substantial performance boost, enabling Nginx to handle high‑concurrency workloads efficiently.