Hostilla.pl IT glossary
What is Varnish?
Varnish is an HTTP caching layer used to speed up website responses.
Definition
Varnish is an HTTP caching layer used to speed up website responses.
What does it mean in practice?
For websites and online services, Varnish affects response time, reliability, resource usage and the quality of the network path.
A practical Hostilla.pl example
Measure the same URL from a repeatable location before and after a change. Varnish should be correlated with server response time, application logs, resource use, caching and the network path rather than judged from one browser refresh.
What should you check?
- the exact URL, device, location and test time
- a baseline for response time and page metrics
- PHP, database, disk, cache and resource usage
- one controlled change followed by the same test