What Is The Cache Hit Ratio and The Most 3 Quick Tips to Increase It?

The cache hit ratio is calculated by dividing the number of cache hits by the total number of cache requests (the sum of the number of cache hits and the number of cache misses). Finally, that result is multiplied by 100 to get the percentage.

Hit Ratio

The cache hit ratio is one of the metrics in the cache memories, used to determine the cache’s efficiency. A Content Delivery Network (CDN) stores your website’s content in the proxy/ edge server for fast delivery to your users worldwide. 

By measuring the cache hit ratio, we can measure how many content requests your cache can effectively deliver. Here, we will explain what the hit ratio is and how to measure it. We will also look at three quick tips to increase the cache hit ratio. 

What is Cache and How Does it Work?

Before discussing the cache hit ratio, you need to understand what a cache is and the importance of using a caching mechanism on your website & how cache works.

A cache is a temporary memory that stores your website’s data or static content so that when a user visits your webpage, that content will render much faster. By using a cache you can boost your website’s load time for a better user experience.

The resources you need to cache include:

  • HTML files
  • CSS stylesheets
  • JavaScript files
  • Media files (images, videos, and others)

Let’s understand the cache mechanism in simple words. When a user visits your website for the first time, the browser loads the static resources and stores them in the browser cache. The next time that user revisits your website, the stored resources are served from the browser cache.

If the requested content is not available in the browser cache, then the HTTP request will go to the CDN cache. If that requested content is present in the CDN cache, then it will be served from there.

Finally, that HTTP request will go to the origin server. If the content is present in server memory, it will be served from the server cache. Otherwise, it will be served from the hard disk or storage

Let us understand this cache mechanism with an example.

  • A visitor opens the cache vs cookies blog on RabbitLoader.com.
  • If images are present in the cache, it will serve from the cache in RabbitLoader, increasing the cache hit ratio.
Image Cached
  • Otherwise, it will serve from the origin server (Hostinger). This is known as a cache miss.

What is the Cache Hit and Hit Ratio?

A cache hit happens when a user requests data or content from a cache and that cache is able to fulfill that HTTP request, indicating the data/ content is successfully served from the cache. 

Cache Hit, hit ratio,

The cache hit ratio is an important metric for CDNs that tells how efficiently a CDN can serve the content that is stored in the cache. It’s measured as the number of cache hits divided by the total HTTP request (cache hit and cache miss).

What is the Cache Miss and Miss Ratio?

A cache miss ratio occurs when the requested content or data is not available in the CDN cache. Thus, the requested content will serve from the origin server instead of the CDN cache.

cache miss

The cache miss ratio is calculated as a percentage of the number of cache misses and the total number of cache hits and cache misses. 

The Example of Cache Hit and Cache Miss

Now you have a brief knowledge of cache hit and cache miss. Now, you will understand with an example. 

RabbitLoader publishes a new blog on its website, and you are the first visitor to this blog for an edge location. So, when your browser sends an HTTP request for the content of this blog, the content will be sent from the origin server and loaded in the CDN server. Because the content is not available in CDN, a cache miss occurs in CDN.

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The next time anyone opens this blog, the content can be served from the nearest edge server instead of the origin server. This can be described as a cache hit.

How to Calculate the Cache Hit Ratio and Cache Miss Ratio?

As mentioned earlier, you can calculate the hit rate by dividing the number of cache hits by the total number of cache requests (the sum of the number of cache hits and the number of cache misses). Finally, that result is multiplied by 100 to get the percentage.

Hit Ratio, cache hit ratio,

The easiest way to calculate hit ratios is by using the below formula: 

Cache hit rate (the number of cache hits/ Total cache requests)*100

To calculate the cache miss ratio, you need to divide the number of cache misses by the total number of HTTP requests and then multiply by 100.

missratio, miss ratio, hit ratio

Cache miss rate= (the number of cache misses/ (Total cache requests)*100

Let’s understand with an example. Let’s say the total number of cache requests is 50, and the cache hits are 26. 

Cache hit rate= (26/50)*100

                      = 52%

Cache miss rate= (100-52)%

                          = 48%

What is the Ideal Cache Hit Ratio?

By getting the cache metrics: cache hit rate and cache miss rate, you can determine the CDN performance. If your website is made up of lots of static content, then your cache hit rate should be greater than 95 %

Cache hit ratioRemarks
Greater than 95%Ideal cache hit rate
90% – 95%High cache hit rate
Below 90%Low cache hit rate

You need to keep in mind that if your website has a lot of dynamic content, it may have a lower cache hit ratio.

3 Ways to Increase Cache Hit Ratio for Your Website 

As you can see, the cache hit rate determines the cache performance for your website. Therefore, If the cache hit rate is low for your website, you need to increase it to boost your website’s performance. Let’s list the 3 most common ways to increase this hit rate:

  • Set up a cache-control header based on your website’s requirements
  • Increase the cache size and optimize the cache usage
  • Cache invalidation

Set Up a Cache-Control Header Based on Your Website’s Requirements

cache control max age

By cache-control header, you can set the caching rules for optimizing your website’s data/ content serving. Here we will explore some cache-control header rules that include:

  • no-cache indicates that though the requested content is available in the edge cache server, the HTTP response needs to be validated from the origin server before serving it.  
  • max-age indicates the amount of time that the cache can store your website’s content. It can be measured in seconds.
  • private tells your resources can be only stored in a private cache.
cache control

Optimize the Cache Size and Cache Usage

Optimizing the cache size and selecting the content to cache properly can increase your cache hit ratio. You need to ensure that the frequently accessed resources are stored in the cache by prioritizing high-demand resources. 

Cache Invalidation 

To increase the hit ratio, you need to ensure that your cached content remains up-to-date. To avoid stale content, you must invalidate or refresh your cache by setting up the cache control:max-age

How RabbitLoader Will Help You to Increase Your Cache Hit Ratio?

As you can see, the above ways are time-consuming. Being from a non-tech background, these strategies can look impossible to implement. But don’t panic. RabbitLoader has the solution. Let’s explore how RabbitLoader works to improve your cache hit ratio.

  • You can easily install Rabbitloader to optimize your website’s performance, it will cache your website’s assets such as CSS sheets, Scripts, images, and HTML files for the right amount of time. Therefore, by storing your website’s assets, RabbitLoader will increase your website’s cache hit ratio and reduce the load on your origin server.
  • RabbitLoader has a premium Content Delivery Network (CDN) with 300+ PoPs worldwide. By using RabbitLoader, you can ensure that your content is up-to-date (stale-free). It will also help you reduce your network latency with its 300+ PoPs.
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Improve Your Website’s Performance and SEO Ranking with Web Caching

In the modern internet era, websites have become an essential part of our daily lives. The internet provides a platform for users to connect, communicate, and consume information, which makes the web browser an essential tool. However, with the rise of complex web applications and dynamic content, web browsing can become slow, which affects the user experience. 

To combat this, Web Caching has become an essential tool to increase the speed and efficiency of web browsing.

In this blog post, we will discuss Web Caching, its importance, and best practices to optimize caching behavior. We will also cover the different types of web caches, how they work, and the impact of caching on web browsing.

What is Web Caching?

Web Caching is the process of storing web content, such as HTML pages, images, and other objects, in a cache server. When a user requests a web page, the caching server checks if the page is already cached. If the page is cached, the caching server returns the page from its cache, which reduces the number of requests to the origin server, making web browsing faster.

          Web Caching can occur at various levels of the web architecture, including web browsers, proxy servers, and content delivery networks (CDNs). Web Caching is crucial for large-scale websites, where the same content is accessed by multiple users. By caching content, web servers can reduce the load on their servers, and improve the user experience.

Web caching

FAQs:

Why is Web Caching important?

Web Caching is important because it increases the speed and efficiency of web browsing, reduces the load on servers, and improves the user experience.

Types of Web Caches

Web Caching can occur in various forms, depending on the caching layer. The most common types of web caches are:

Browser Cache

Proxy Cache

CDN Cache

  1. Browser Cache: 

The browser cache is a cache that stores web content on the user’s computer. When a user visits a website, the browser stores the content in its cache. When the user revisits the website, the browser can retrieve the content from the cache, reducing the number of requests to the origin server.

Browser caching has a significant impact on web browsing speed. When the user revisits a website, the browser only needs to retrieve new or updated content, which reduces the amount of data transferred and reduces the load on the web server.

  1. Proxy Cache:

A proxy cache is a cache server that sits between the client and the origin server. When a user requests a web page, the request is sent to the proxy cache instead of the origin server. If the page is already cached, the proxy cache returns the content from its cache. If the page is not cached, the proxy cache requests the content from the origin server and caches it for future requests.

Proxy caching can significantly reduce the load on the origin server, and improve the user experience. Proxy caching is commonly used in enterprise networks to reduce the load on the internet connection and filter content.

  1. CDN Cache:

CDN caching is a cache server that sits between the origin server and the client. CDNs cache content at multiple locations around the world, which reduces the distance between the client and the origin server. 

When a user requests a web page, the request is sent to the CDN server closest to the user. If the page is already cached, the CDN server returns the content from its cache. If the page is not cached, the CDN server requests the content from the origin server and caches it for future requests.

CDN caching can significantly reduce the latency and improve the user experience. CDNs are commonly used for large-scale websites and web applications that serve users from different parts of the world.

How Web Caching Works?

Web Caching works by storing web content in a cache server, and checking if the content is already cached before sending a request to the origin server. The caching server keeps track of the cached content and its expiration time, and deletes expired content to make room for new content. When a user requests a web page, the caching server checks if the content is already cached. If the content is cached and has not expired, the caching server returns the content from its cache. If the content is not cached, the caching server requests the content from the origin server and caches it for future requests.

Web Caching works by storing frequently accessed web content in a cache server and serving that content to clients directly from the cache, instead of retrieving it from the original server every time.

When a user requests a web page, the caching server checks if the page is already cached. If it is, the caching server returns the page from its cache to the user’s browser, saving the time and resources required to retrieve the page from the origin server. 

If the page is not cached, the caching server requests it from the origin server and caches it for future requests.

To ensure that the cached content is up-to-date, Web Caching servers also set expiration times. These expiration times indicate how long the content should remain in the cache before it is removed or refreshed.

When a user requests a page that is not cached, the caching server retrieves it from the origin server and stores a copy in the cache for future requests. The next time the user requests the same page, the caching server will return the cached copy, provided it has not expired. 

If the cached copy has expired, the caching server will request a fresh copy from the origin server and replace the expired content in the cache with the new content.

Web Caching can occur at different levels of the web architecture, including the browser, proxy servers, and content delivery networks. Browser caching stores content on the user’s computer, while proxy caching stores content on a server between the client and the origin server. 

CDN caching is a specialized type of caching that distributes content to multiple servers located around the world to reduce latency and improve performance for users in different regions.

In addition to improving website performance, Web Caching also reduces the load on origin servers by reducing the number of requests they receive. This helps improve the scalability and reliability of web applications and reduces the risk of downtime or performance degradation during periods of high traffic.

Caching servers use cache-control headers and ETag headers to manage cached content. Cache-control headers define how long the content should be cached and under what conditions the content should be revalidated. ETag headers are used to identify cached content and compare it to the current version of the content on the origin server.

Check out: Guide to Resource Loading

FAQs:

What is the Impact of Web Caching on Website Performance?

Web Caching can significantly reduce latency and improve website performance by reducing the number of requests to the origin server and decreasing the amount of data transferred.

Importance of Web Caching

Web Caching is critical for improving the speed and efficiency of web browsing, which is essential for modern web applications and websites. The importance of Web Caching can be explained in the following ways:

  1. Faster Web Browsing: 

Web Caching reduces the number of requests to the origin server, making web browsing faster.

  1. Reduced Server Load:

 By caching content, web servers can reduce the load on their servers, which improves server performance and reduces the risk of server crashes.

CDN caching
  1. Improved Performance and User Experience:

Web Caching can significantly improve the performance and user experience of websites and web applications. By caching web content, the load on the origin server is reduced, which reduces the time it takes for a web page to load. 

When a user visits a website, the browser or proxy cache can retrieve the cached content, which can be displayed almost instantly, resulting in a faster browsing experience. 

This can be especially beneficial for large websites with heavy traffic and complex web applications, where the number of requests to the origin server can be substantial.

  1. Reduced Bandwidth and Network Traffic:

Web Caching can significantly reduce the bandwidth and network traffic required for web browsing. When web content is cached, it can be retrieved locally, reducing the amount of data that needs to be transferred over the internet. 

This reduces the load on the network infrastructure, especially for websites and web applications that generate a lot of traffic. By reducing the amount of data transferred, Web Caching can also help lower the costs associated with bandwidth usage and network infrastructure.

Web Caching
  1. Improved Scalability and Availability:

Web Caching can significantly improve the scalability and availability of websites and web applications. By reducing the load on the origin server, Web Caching can help improve the scalability of web applications, making them more capable of handling large numbers of users.

 Additionally, Web Caching can help improve the availability of web content by reducing the risk of server overload and downtime. In case of server downtime, users can still access the cached content, ensuring a smooth browsing experience.

  1. Better Search Engine Rankings:

Web Caching can also improve search engine rankings. Search engines, such as Google, rank websites based on the loading speed, which can be influenced by Web Caching. Websites that load faster due to Web Caching may rank higher in search engine results, resulting in more traffic and better visibility.

Web Caching

In conclusion, Web Caching is a critical tool for improving the performance, scalability, and availability of websites and web applications. By reducing the load on the origin server, Web Caching can significantly improve the speed and efficiency of web browsing, resulting in a better user experience. Additionally, web Caching can reduce the amount of bandwidth and network traffic required, making web browsing more cost-effective. Therefore, it is essential to implement Web Caching effectively to improve the overall performance and user experience of websites and web applications.

FAQs:

How Does Web Caching Affect SEO Ranking?

Web Caching can indirectly affect SEO ranking by improving website performance, which is a factor in search engine rankings. Faster-loading websites with better user experience are generally favoured by search engines.

Check also: Lazy Load Background Images

Best Practices for Web Caching

To optimize the caching behavior, it is essential to follow best practices for Web Caching. Some of the best practices for Web Caching are:

  1. Set Appropriate Cache-Control Headers: 

Set appropriate cache-control headers for each resource to define how long the content should be cached and under what conditions the content should be revalidated.

  1. Use ETag Headers:

 Use ETag headers to identify cached content and compare it to the current version of the content on the origin server.

  1. Cache Static Content: 

Cache static content, such as images and stylesheets, as it rarely changes and can significantly improve the web browsing speed.

  1. Cache Dynamic Content Selectively:

 Cache dynamic content selectively, as it changes frequently, and caching it may not be effective.

Regularly monitor the caching behavior: Regularly monitor the caching behavior to ensure that the content is being cached correctly and to identify any issues with the caching behavior.

Conclusion:

In conclusion, Web Caching is an essential tool for improving the speed and efficiency of web browsing. It reduces the number of requests to the origin server, which reduces latency and improves the user experience. Web Caching can occur at various levels of the web architecture, including web browsers, proxy servers, and CDNs.

Web Caching is particularly important for large-scale websites and web applications that serve a significant number of users. Caching content reduces the load on the web server, which improves the server’s response time and reduces the risk of server overload.

To optimize the caching behavior, it is essential to follow best practices such as setting appropriate cache headers, caching frequently accessed content, and avoiding caching sensitive information. By following these best practices, web developers can ensure that caching provides the best possible performance benefits.

In today’s world, where web browsing is an integral part of our daily lives, Web Caching has become more critical than ever. Using Web Caching can make web browsing faster, more efficient, and more enjoyable for users.