Determine the CPU & RAM specs required for your VPS

How to Size a VPS (Virtual Private Server) for Your Website

Sizing your virtual server incorrectly leads to two major issues: either you overpay for unused hardware (e.g. paying $80/mo for a 4-core node when you only use 5% of its capacity), or your server runs out of RAM during a traffic spike, returning "502 Bad Gateway" or "500 Internal Server Error" warnings.

The two most critical performance bottlenecks are **database lookups** and **active PHP threads**. When a user requests a page, the server spawns a PHP process that executes database queries.

The Power of Server-Side Caching:

If you use full page caching (Varnish, Nginx helper rules, or Redis caching), your server doesn't compile PHP or look up database queries for every visit. Instead, it serves a pre-compiled HTML page directly from memory, which reduces CPU load by up to **90%**. This caching allows a cheap **1 Core / 1GB RAM VPS** to easily serve millions of cached page views monthly.