This rule triggers when PageSpeed Insights detects that your server response time is above 200 ms.
Server response time measures how long it takes to load the necessary HTML to begin rendering the page from your server, subtracting out the network latency between Google and your server. There may be variance from one run to the next, but the differences should not be too large. In fact, highly variable server response time may indicate an underlying performance issue.
You should reduce your server response time under 200ms. There are dozens of potential factors which may slow down the response of your server: slow application logic, slow database queries, slow routing, frameworks, libraries, resource CPU starvation, or memory starvation. You need to consider all of these factors to improve your server's response time. The first step to uncovering why server response time is high is to measure. Then, with data in hand, consult the appropriate guides for how to address the problem. Once the issues are resolved, you must continue measuring your server response times and address any future performance bottlenecks.
- Gather and inspect existing performance and data. If none is available, evaluate using an automated web application monitoring solution (there are hosted and open source versions available for most platforms), or add custom instrumentation.
- Identify and fix top performance bottlenecks. If you are using a popular web framework, or content management platform, consult the documentation for performance optimization best practices.
- Monitor and alert for any future performance regressions!