How to optimize and speed up your server by more than 20%?

Updated: 28 September 2026 · Applies to: Ubuntu 24.04, Debian 12, AlmaLinux 9 and Rocky Linux 9 and cPanel & WHM 138

Most server speed gains come from a few changes, checked in order. How much each helps depends on your site; measure before and after (for example with PageSpeed Insights and your server's load average).

1. Cache

• OPcache for PHP code: on by default in current PHP versions; give it enough memory (opcache.memory_consumption=256 on busy servers).
• Page cache: a caching plugin for WordPress, or NGINX/Varnish in front of the site, so most visits need no PHP or database work.
• Object cache: Redis or Valkey for repeated database queries (see "Redis cache for speeding up your WordPress site").

2. Use current software

• PHP 8.3 or newer is much faster than PHP 7; choose it in Software › MultiPHP Manager after testing your site.
• Keep the operating system, web server and database updated.

3. Tune PHP-FPM and the database

• Set PHP-FPM pm.max_children to what your RAM allows (RAM for PHP ÷ memory per PHP process).
• Give MariaDB enough innodb_buffer_pool_size and fix slow queries (see "MySQL tweaking, best practices and tips for SysAdmin").

4. Send less data

• Enable compression (Brotli or gzip) and HTTP/2.
• Resize and compress images (WebP or AVIF), and lazy-load images below the first screen.
• Use browser caching headers for static files, and a CDN for visitors far from your server.

5. Watch the server

• Check load, memory and disk with htop and monitoring (see "Monitoring Performance Of CentOS 8/7 Server Using Netdata").
• Look for heavy cron jobs, bots and large log files.

Tip: Ucartz managed plans include optimisation help from our engineers. On unmanaged servers you can hire an expert for a one-off performance review.