Common performance issues

# Misconfiguration

Configuration errors are among the most common causes of performance issues. These problems often stem from development settings being used in production, improper caching configurations, or conflicting plugins and extensions. What works fine during development can become a major bottleneck when deployed to a live environment with real traffic and data volumes.

• All assets are re-generated with each deployment or even page load
• The production environment is set to development
• A plugin creates a ton of load or conflicts with other config
• Slow MySQL queries

# External sources

Modern applications rarely exist in isolation - they depend on external APIs, CDNs, payment processors, and other third-party services. When these external dependencies experience issues, your application's performance suffers as a direct consequence. A single slow external service can create cascading delays throughout your entire application.

• A third party service is down or slow

# Data threshold reached

Applications that perform beautifully during development and testing can hit performance walls when they encounter real-world data volumes. What seems fast with a few hundred test records can become painfully slow with thousands of production records. This is one of the most surprising issues for developers.

• A MySQL query that is fast locally with little testing data, is slow in production

# Usage patterns changed

Maybe the number of visitors has increased, or how people and even bots are interacting with a project. User behavior and traffic patterns are constantly evolving, and applications that were designed for certain usage assumptions can struggle when those patterns change. Sudden traffic spikes, different user workflows, or unexpected bot activity can expose performance weaknesses that weren't apparent under normal conditions. These changes often happen gradually until they cross a critical threshold, making the performance degradation seem sudden.

• A website was linked from a popular blog and get's more visits
• A new user is uploading images of a larger size
• Bots are aggressively curling all pages