Knowledge Base

Why Does My E-commerce Website Slow Down When Many Visitors Arrive at the Same Time?

Total visitor count does not accurately describe application load

For e-commerce sizing, concurrent dynamic requests are much more important than total daily visitors.

Ten thousand visitors distributed throughout the day may generate a moderate workload, while a few hundred customers arriving within minutes during a campaign or promotion may create significantly higher demand.

Why is e-commerce different from a static website?

Product searches, filters, pricing, inventory, carts, authentication, checkout and customer accounts often require PHP execution and database queries.

PHP worker saturation

As concurrency increases, all available PHP-FPM workers may become busy. New requests then wait in a queue and response times progressively increase.

Database concurrency

Each PHP process may generate multiple queries. Increasing PHP workers without considering the database may simply move the bottleneck to MySQL or MariaDB.

Memory usage

Every worker consumes memory. Excessive worker counts can exhaust RAM and cause swap usage, which may severely reduce performance.

Caching

Caching reduces workload for public pages and catalog content, while carts, checkout and personalized areas require different handling.

How KWEB approaches traffic peaks

The environment is sized according to concurrency, process memory consumption, database behavior, caching and actual application workload.