User Manual: Understanding Cache

Note: This article content is applicable to PB series website solutions (based on PHP architecture)

The Importance of Website Access Speed

Website access speed is closely related to user experience and search engine optimization (SEO). Utilizing caching technology can significantly improve website loading speed, thus enhancing user experience. When users visit a fast-loading website, they are more likely to stay longer, browse more pages, which lowers bounce rates and increases conversion rates.

For SEO, Google search engine considers website loading speed as one of the ranking factors. A fast-loading website can attain higher search rankings because Google believes that fast-loading websites provide better user experience. Additionally, caching technology can reduce server load, improve website response time, which also helps search engine crawlers to more effectively fetch and index website content.

In summary, leveraging caching technology to optimize website access speed not only enhances user experience but also improves website SEO performance.

Configuration of Cache Policy

Reasonable use of caching technology enables the website to achieve performance experience. However, using this technology also requires setting up different caching mechanisms to deal with the complex usage scenarios of the website, including:

1. The cache expiration period for different types of pages. For example, the homepage of the website, main pages of sections, etc., need to have a shorter cache expiration period based on their update frequency, while pages such as articles, products, services, etc., with lower update frequency, require a longer cache expiration period.
2. Special HTTP request methods, URL parameters, cookies, and access paths that do not require caching. This could be POST requests or background access directories, for example.
3. Timely cleaning of corresponding cache data when data is updated, such as when you modify the content of a page in the backend or when a user adds a comment to content.

You can easily manage cache times and cleaning methods for various pages via the system dashboard (developer account required). The system also supports unified cache management.

When your website is deployed, we will configure cache strategy items for you. Feel free to contact us if you need assistance.

What You Need to Know

1. The caching system mainly targets users visiting your website. Once you have successfully logged into your account in the system, you can preview the website content in real-time. Except for the database cache, all other caching mechanisms stop working. This is done to allow you to better manage and preview your website content.
2. Pages with enabled caching are cached only after the first request is made for the related page data. When the page is requested again within the cache expiration period, it receives a cached data request, significantly improving access speed.
3. Once the cache time for a page expires, new requests will automatically generate new cache data.
4. URLs, HTTP requests, and directories with special parameters will not trigger caching according to the rules set.

Several Built-in Caching Systems

Markup Cache

Cache for code snippets or data, file storage location: /site/assets/cache/MarkupCache/

Take website settings as an example. Every time we save system parameters, all configuration items are saved in JSON format in "sysConfigs". The parameters can be retrieved from the cache file when needed.

Similarly, some complex and voluminous data may also be stored in MarkupCache, greatly improving system performance.

Page Cache

Cache for page data accessed by users, file storage location: /site/assets/cache/Page/

When a user visits a page of your website, the system needs to process all the data to be displayed, such as the top menu, main content, sidebar, footer, etc. All the required data is stored in the database, and when a user accesses a page, the system retrieves the necessary data from the database. This is how the system operates. When a large number of users flood the site and it becomes busy, server load also increases. If your server's computing power is not sufficient, your site may become slow or even crash.

The purpose of page caching (PageCache) is to store page data on the server disk, avoiding repeated queries to the database and thus significantly reducing server load.

Through a developer account in the website backend, you can easily set the caching time and triggering mechanism for target pages.

Front-end File Cache (CSS/JS)

Merges and compresses frontend JS/CSS files to generate new cache files, file storage location: /site/assets/aiom/

Merging Files

When a browser loads a webpage, each file resource needs to be retrieved through HTTP requests. Merging multiple JS/CSS files can reduce network requests and thus reduce page loading time.

File Compression

The purpose of compressing JS and CSS files is to reduce their size by removing unnecessary spaces, comments, line breaks, etc., which can significantly reduce file size and speed up file download.

Reducing file size and HTTP request count can speed up webpage loading. This is very important for user experience and search engine optimization (SEO) as page loading speed is one of the key indicators for evaluating website performance.

Note: If this item does not appear in your system, it is because it is merged into the page cache.

Database Cache

Cache for complex database queries, cached in the caches table of the database

Take a real estate website as an example. Users may perform complex conditional combined queries for property information, such as location, property type, price, number of rooms, bedrooms, bathrooms, environment, facilities, floor, etc.

As data grows, the time required for queries also increases. Therefore, correct use of caching technology becomes crucial.

Note: It is possible that this setting item may not appear in your backend, depending on the circumstances.

FastCache

Accelerates pages to HTML static pages, file storage location: /site/assets/fastCache/

phpFastCache is a high-performance backend caching system. It aims to speed up dynamic web applications by reducing database load, almost to zero, thus providing users with faster page loading times and better resource utilization.

Thanks to phpFastCache, once this feature is enabled, requests to your website will be served from the cache, avoiding passing through the framework entry and achieving page loading speeds close to those of static HTML pages.

When users first access a page, it is dynamically generated and stored in the cache. Then, if other users access the same page, its content will be directly retrieved from the cache without the need for regeneration, thus improving page loading speed and performance.