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WordPress Performance Optimization

Caching constants, database cleanup SQL, plugin stack, and wp-config settings to achieve Lighthouse 90+ on WordPress sites.

performancecachingspeedwp-rocket
Agent trigger phrases: wordpress slow · speed up wordpress · wordpress performance · wp rocket setup · wordpress caching

Target: Lighthouse 90+ across all categories. LCP <2.5s mobile, CLS <0.1.

wp-config.php Caching Constants

define('WP_CACHE', true);
define('COMPRESS_CSS', true);
define('COMPRESS_SCRIPTS', true);
define('CONCATENATE_SCRIPTS', false); // false = better compatibility
define('ENFORCE_GZIP', true);

Plugin Stack (Preferred)

| Function | Plugin | |---------|--------| | Caching | WP Rocket | | Image optimization | ShortPixel (WebP conversion) | | CDN | Cloudflare | | Database cleanup | WP-Optimize | | Script management | Perfmatters |

Database Cleanup SQL

Run in phpMyAdmin or via WP-CLI:

-- Remove post revisions
DELETE FROM wp_posts WHERE post_type = 'revision';

-- Remove spam comments
DELETE FROM wp_comments WHERE comment_approved = 'spam';

-- Remove auto-draft posts
DELETE FROM wp_posts WHERE post_status = 'auto-draft';

-- Optimize tables
OPTIMIZE TABLE wp_posts, wp_postmeta, wp_options, wp_comments;

Or via WP-CLI: wp db optimize

WP Rocket Key Settings

  • Cache: Enable page caching, cache for mobile
  • File Optimization: Minify CSS + JS, combine CSS, defer JS
  • Media: LazyLoad images and iframes
  • Preload: Preload cache on publish, sitemap-based preloading
  • CDN: Connect Cloudflare zone

Image Optimization

  • Convert all images to WebP (ShortPixel or Imagify)
  • Set LCP hero image with fetchpriority="high" and a preload link tag
  • Never lazy-load above-the-fold images

Elementor Performance Settings

| Setting | Value | |---------|-------| | CSS Print Method | External File | | Improved Asset Loading | Enabled | | Font Display | Swap | | Google Fonts | Disable (use local fonts) | | Font Awesome | Load used icons only |