Caching is one of the most effective ways to reduce the amount of work your server needs to perform, particularly when large numbers of visitors are requesting the same content.
Without an effective caching strategy, your application might repeatedly execute PHP code, query the database and generate HTML for pages that haven’t meaningfully changed between requests. During periods of increased traffic, that unnecessary processing can consume a significant amount of server capacity.
Full-page caching allows a previously generated HTML response to be served without executing the application again. This can work particularly well for public-facing content such as promotional landing pages, blog articles and certain product or category pages. However, the suitability of full-page caching depends on how your website handles customer sessions, pricing, stock availability and personalised content.
Shopping baskets, account pages and checkout processes generally require more careful handling because the information displayed is specific to an individual customer. Incorrect caching rules can result in outdated information being displayed or, in more serious cases, customer-specific content being served to the wrong visitor.
Reducing origin server requests with Cloudflare
Cloudflare can provide an additional caching layer by serving eligible content from its distributed network rather than forwarding every request to your origin server. Static assets such as images, stylesheets, JavaScript files and fonts are obvious candidates for edge caching, as they can typically be reused across many visitors. Depending on the website’s architecture, Cloudflare can also cache generated HTML responses, potentially reducing the number of requests that reach the application.
For a busy eCommerce website, this can make a substantial difference. If thousands of visitors are accessing the same promotional landing page, serving that content from Cloudflare’s cache means your origin server doesn’t need to generate the page for every request.
However, Cloudflare isn’t a solution to every performance problem. Requests involving customer sessions, checkout functionality, personalised pricing or other dynamic operations may still need to reach the origin server. If those requests are responsible for the majority of your server load, adding a CDN alone might have a relatively limited impact.
Caching also needs to be configured with appropriate expiration and invalidation rules. A promotional page that displays outdated pricing or availability can cause problems, while overly aggressive cache expiration can lead to unnecessary requests reaching your origin.
Another consideration is what happens when a popular cached page expires. If hundreds of requests arrive simultaneously and all trigger regeneration of the same content, the resulting spike in origin traffic can create what’s known as a cache stampede. Techniques such as serving stale content while a fresh response is generated, request coalescing and cache warming can help, depending on the platform and caching solution.
Object caching with Redis
For applications that rely heavily on database queries, object caching can provide another useful optimisation. Redis is commonly used to store frequently accessed data in memory, reducing the need to retrieve or calculate the same information repeatedly. This might include application configuration, frequently requested product information or the results of expensive database queries.
Both WordPress and Laravel applications can benefit from Redis when it’s implemented appropriately, although simply installing Redis won’t automatically improve every website. You need to understand which operations are expensive, what data can safely be cached and how that cache should be invalidated when information changes.
For eCommerce applications, particular care is needed around stock levels, prices and other information that changes frequently. Caching can reduce database load, but it shouldn’t compromise the accuracy of business-critical data.