Performance Tuning

Performance settings help optimize Chamilo for faster page loads and better resource utilization, especially on platforms with many concurrent users.

Additional reference: Your Chamilo installation includes an extended optimization guide. Open /documentation/optimization.html in a browser (e.g. https://your-chamilo-site/documentation/optimization.html) for server-level recommendations specific to your version.

Symfony Cache

Chamilo 3.0 is built on Symfony, which uses a compiled cache for routing, dependency injection, and templates. Managing this cache is essential for performance.

Clearing the Cache

After configuration changes, deployment, or upgrades, clear the Symfony cache:

# Clear cache for the current environment
php bin/console cache:clear

# For production environments specifically
php bin/console cache:clear --env=prod

In production, always ensure APP_ENV=prod is set in your .env.local file. The development environment (APP_ENV=dev) includes extensive debugging overhead and should never be used in production.

Cache Warmup

After clearing cache, warm it up to pre-compile templates and configuration:

php bin/console cache:warmup --env=prod

Caching Strategies

Strategy	Description
OPcache	PHP's built-in opcode cache. Ensure it is enabled in your php.ini with adequate memory (opcache.memory_consumption=256). This is the single most impactful performance optimization.
APCu	An in-memory key-value cache used by Symfony for storing metadata. Install the APCu PHP extension and configure it in your Symfony cache configuration.
Redis / Memcached	For high-traffic platforms, configure an external cache backend. Set the cache adapter in config/packages/cache.yaml.

Recommended OPcache Settings

opcache.enable=1
opcache.memory_consumption=256
opcache.max_accelerated_files=20000
opcache.validate_timestamps=0   ; Set to 0 in production for best performance
opcache.revalidate_freq=0

When validate_timestamps is set to 0, you must clear OPcache after deploying new code (restart PHP-FPM or call opcache_reset()).

Lazy Loading

Setting	Description
Lazy-load images	Enables the loading="lazy" attribute on images so that off-screen images load only when scrolled into view. Reduces initial page load time.
Deferred JavaScript loading	Load non-critical JavaScript files asynchronously to avoid blocking page rendering.

CDN (Content Delivery Network)

For platforms serving users across multiple geographic regions, a CDN can significantly improve load times for static assets (CSS, JavaScript, images).

To configure a CDN:

1. Set up a CDN distribution (e.g., CloudFront, Cloudflare, or another provider) pointing to your Chamilo server.

2. Configure the asset base URL in your environment or Symfony configuration so that static assets are served through the CDN.

3. Set appropriate cache headers for static files (long expiry for versioned assets).

Database Optimization

Action	Description
Use database connection pooling	For high-concurrency platforms, configure connection pooling to reduce overhead of establishing database connections.
Optimize queries	Chamilo includes database indexes for common queries. Run ANALYZE TABLE periodically on MySQL/MariaDB to keep query planner statistics current.
Separate database server	For large installations, run the database on a dedicated server rather than sharing resources with the web server.

Web Server Configuration

Optimization	Description
Enable gzip/brotli compression	Compress HTML, CSS, and JavaScript responses. Most web servers support this natively.
Static file caching	Set long Cache-Control and Expires headers for static assets.
PHP-FPM tuning	Adjust pm.max_children, pm.start_servers, and pm.max_requests based on available RAM and expected concurrency.
HTTP/2	Enable HTTP/2 in your web server for multiplexed connections and header compression.

Tips

• OPcache is the single biggest win -- Ensure it is enabled and properly sized before pursuing other optimizations.

• Never run production with APP_ENV=dev -- The debug toolbar and profiler add significant overhead to every request.

• Monitor before tuning -- Use tools like New Relic, Blackfire, or Symfony's built-in profiler (in dev mode) to identify actual bottlenecks rather than guessing.

• Warm the cache after every deployment to avoid the first user hitting a slow uncached request.