Koha Performance Optimization: Essential Techniques for Speed

Note: This article was originally written in 2021 for Koha on Ubuntu 20.04. Some specific commands, package names, file paths, and configuration options may have changed in current Koha releases (25.05, 25.11). The general principles remain sound, but verify any specific commands against the Koha manual for your version before running them on a production system. KohaSupport customers on the managed platform do not need to apply these manually — performance configuration is handled as part of your hosted setup.

A slow library system frustrates staff and patrons alike. Before investing in expensive hardware upgrades, implement these performance optimization techniques to improve your Koha system’s speed through better configuration, caching, and delivery.

Why Koha Performance Optimization Matters

System performance directly impacts:

• Staff Productivity - Faster cataloging, circulation, and acquisitions workflows
• Patron Satisfaction - Quick OPAC searches and responsive checkouts
• System Reliability - Lower server load reduces timeouts and crashes
• Cost Efficiency - Maximize existing hardware before upgrading

Most performance issues stem from default configurations that don’t leverage available optimization tools. These four techniques address the most common bottlenecks.

1. Enable Memcached

Memcached is a high-performance, distributed memory caching system that can dramatically speed up your Koha installation.

Installation

# Install Memcached
sudo apt-get update
sudo apt-get install memcached libmemcached-tools

# Start the service
sudo systemctl start memcached
sudo systemctl enable memcached

Configure Koha to Use Memcached

Edit your Koha configuration file:

sudo nano /etc/koha/sites/library/koha-conf.xml

Add the following within the <config> section:

<memcached_servers>127.0.0.1:11211</memcached_servers>
<memcached_namespace>KOHA</memcached_namespace>

Restart Apache:

sudo systemctl restart apache2

Expected Result: Many libraries see noticeably faster page loads for searches and catalog displays after enabling caching correctly.

2. Enable Plack

Plack is a PSGI (Perl Web Server Gateway Interface) toolkit that keeps Koha’s Perl modules loaded in memory, eliminating startup time on each request.

Enable Plack

# Enable Plack for your Koha instance
sudo koha-plack --enable library
sudo koha-plack --start library

# Verify it's running
sudo koha-plack --status library

Configure Apache

# Restart Apache to apply changes
sudo systemctl restart apache2

Expected Result: Staff interface response times often improve when Plack is configured and running correctly.

3. Enable Apache Caching

Apache’s mod_cache can cache static resources and reduce server load.

Enable Required Modules

# Enable caching modules
sudo a2enmod cache
sudo a2enmod cache_disk
sudo a2enmod expires
sudo a2enmod headers

# Restart Apache
sudo systemctl restart apache2

Configure Caching

Edit your Koha Apache configuration:

sudo nano /etc/apache2/sites-available/library.conf

Add these directives:

# Enable caching
CacheEnable disk /
CacheRoot /var/cache/apache2/mod_cache_disk
CacheDefaultExpire 3600
CacheMaxExpire 86400

# Cache static assets
<FilesMatch "\.(jpg|jpeg|png|gif|css|js|ico|woff|woff2)$">
    ExpiresActive On
    ExpiresDefault "access plus 1 month"
    Header append Cache-Control "public"
</FilesMatch>

Create cache directory:

sudo mkdir -p /var/cache/apache2/mod_cache_disk
sudo chown www-data:www-data /var/cache/apache2/mod_cache_disk
sudo systemctl restart apache2

Expected Result: Static assets can load faster and origin-server bandwidth usage may drop when cache settings are working as intended.

4. Use a Content Delivery Network (CDN)

For libraries with remote users or multiple locations, a CDN can dramatically improve asset delivery speed.

Benefits of CDN

• Faster load times for geographically distributed users
• Reduced load on your origin server
• Better handling of traffic spikes
• Built-in DDoS protection

Implementation Options

Option 1: Cloudflare (Free Tier)

1. Sign up at Cloudflare
2. Point your domain’s nameservers to Cloudflare
3. Enable CDN and security features

Option 2: Amazon CloudFront (if already on AWS)

1. Create a CloudFront distribution
2. Point it to your Koha server
3. Update DNS records

Configure Koha for CDN

Update your koha-conf.xml to use CDN URLs for static assets:

<intranetcolorstylesheet>https://cdn.yourdomain.com/intranet.css</intranetcolorstylesheet>
<opaccolorstylesheet>https://cdn.yourdomain.com/opac.css</opaccolorstylesheet>

Expected Result: Remote users may see faster asset delivery when static files are served through a well-configured CDN.

Performance Testing

Before and after implementing these changes, test your performance:

# Test page load time
time curl -s http://your-koha-url/ > /dev/null

# Monitor Apache performance
sudo apachectl status

# Check Memcached stats
echo stats | nc localhost 11211

Combined Impact

When all four optimizations are implemented together:

Troubleshooting

Memcached Not Working

# Check if Memcached is running
sudo systemctl status memcached

# Test connection
telnet localhost 11211

Plack Issues

# Check Plack logs
sudo koha-plack --status library
sudo tail -f /var/log/koha/library/plack.log

Apache Cache Problems

# Clear Apache cache
sudo rm -rf /var/cache/apache2/mod_cache_disk/*
sudo systemctl restart apache2

Maintenance Tips

• Monitor regularly: Set up monitoring for Memcached and Plack services
• Clear cache periodically: After major Koha updates, clear caches
• Update regularly: Keep Koha, Apache, and related packages updated
• Backup before changes: Always backup configurations before modifying

Further Reading

• Enable Memcached on Koha
• Enable Plack on Koha
• Apache Caching Configuration
• CDN Setup for Koha

Need Professional Help?

Our team can help optimize your Koha installation for peak performance. Contact us for a performance audit and optimization service.