So far, we've explored some of the reasons why our site might be slow, and the consequences we face if we do not address performance issues. Although some of the issues we could face may not be easy to solve, we can still effect changes that help improve performance of our sites.
Analysis shows that if a page takes longer than 4–5 seconds to load, then customers will frequently vote with their feet (that is, walk away). Any delay of more than a second can equally lead to a poor user experience.
A great source that can help us understand where some of our issues are is that behemoth, Google. We may knock it for being omnipotent, but it clearly knows some useful tricks!
Google states that our page doesn't have to entirely load within 4–5 seconds, but should be usable within this time; any content that is of a lower priority can be put below the fold or loaded in the background.
At a basic level, Google recommends that our server response time should...