Your MyPressable Control Panel (MPCP) includes advanced site metrics to help you monitor performance and identify trends. One of the most important, yet often misunderstood, metrics is cache efficiency.
You can find this data by navigating to your MyPressable Control Panel → Sites → select your site → Metrics.
This guide explains what the cache efficiency chart means, how our caching system works, and why a “low” efficiency score is often normal.
What is cache efficiency?
The cache efficiency chart shows the percentage of page requests that were served directly from our server-level page cache. A higher percentage indicates that more of your site’s traffic is being delivered from this fast cache, which reduces server load and improves page load times for your visitors.
In the chart, you will see two categories:
- Cached requests (blue): This is the percentage of requests served directly from the cache. These are pages that have been visited more than once within the cache’s time limit.
- Non-cached requests (grey): This is the percentage of requests that required the server to generate a fresh version of the page.
It is important to understand that the grey “non-cached” area does not mean caching is broken. In most cases, it simply reflects your site’s traffic patterns.
How Pressable’s page caching works
Our platform uses a powerful page caching system, batcache, to serve your site as quickly as possible. By default, a cached version of a page is stored for five minutes (this is the cache TTL, or “time to live”). Learn more about batcache here.
For a page to be served from the cache, a specific sequence must happen:
- The first visit: When a visitor loads a page for the first time (or the first time after the cache has expired), our system generates the page fresh. It then stores a copy of that page in the cache. This first visit is counted as a “non-cached request.”
- The second visit (and subsequent visits): If another visitor (or the same one) loads that same page within the five-minute window, they will be served the fast, stored copy directly from the cache. This visit is counted as a “cached request.”
If a page only receives one visit every five minutes, it will constantly be served fresh and will not contribute to your “cached requests” percentage.
Why your cache efficiency might seem low
Even on very busy websites, the cache efficiency percentage can appear low. This is completely normal and is usually caused by one of the following factors:
- Traffic patterns: If your site has many different pages (like a large blog or an e-commerce store with thousands of products), traffic is spread out. Many of your pages may not get the required two visits within five minutes to be served from the cache.
- Dynamic content: Certain parts of a website should not be cached. This includes shopping carts, checkout pages, or content personalized for logged-in users. These requests intentionally bypass the cache to ensure the information is always up to date, and they are counted as “non-cached requests.”
- Single-visit URLs: Many visitors may come to your site from search engines or social media, view a single article or product, and then leave. These single visits within the five-minute window will always be “non-cached requests.”
How to improve cache efficiency
While a low efficiency score is often normal, you can take steps to improve it, especially for your site’s most popular pages:
- Extend your cache duration: For pages that do not change often (like your homepage or “About Us” page), you can increase the cache duration beyond the five-minute default. A longer duration gives a page more time to receive multiple visits and be served from the cache. You can learn how to do this with our Pressable Cache Management plugin guide.
- Identify and fix cache bypassing issues: Sometimes, plugins or themes can add cookies or query strings to URLs that unintentionally prevent pages from being cached. A common example involves tracking features in e-commerce plugins. You can read about a specific case in our article on WooCommerce order attribution tracking cookies.
- Conflict test on a staging site: In rare cases, third-party code (plugins, themes) may conflict with and break our caching. If you believe this to be the case, you can run a conflict test on a staging clone of your site to identify which plugin is responsible. (As this testing involves disabling plugins and potentially your theme, we strongly recommend against doing it on a live site.)
Key takeaway
The cache efficiency metric does not measure if caching is working; it measures how often a cached version of a page is served to a visitor. A low percentage is typically a reflection of your site’s traffic patterns and user behavior, not a problem with the caching system itself.