How to improve website maintainability through PHP cache development

How to improve the maintainability of the website through PHP cache development

PHP is a de facto and widely used Web development language, and its flexibility is its One of the advantages, but it may also cause some performance problems. One of them is the slowdown caused by the need to recalculate the content on every access. In order to improve the performance of the website, we can use caching to reduce calculation time. This article will introduce how to use PHP to develop cache to improve the maintainability of the website, and provide specific code examples.

1. What is cache?

Caching means that on some occasions, in order to speed up data access, a part of the data is taken out in advance and stored in temporary memory. When the data needs to be accessed, it can be read directly from the temporary memory. data, thereby increasing access speed.

2. Why do you need to use cache?

In a web application, some operations need to be performed to generate a response after each user request. This may include reading data from a database, performing calculations, generating HTML code, and more. These operations require a certain amount of time and resources to complete. If we can temporarily cache these responses, we can reduce the calculation time and CPU usage required for these operations, thus improving the performance of the website.

3. Where do you need to use caching in PHP?

First, we need to analyze the content that needs to be cached and determine which content needs to be cached. Secondly, we need to choose a suitable caching technology, such as Memcached or Redis, for caching. Finally, we need to decide when and how to update the cache to ensure our cache is up to date and valid.

4. How to implement PHP caching?

There are many ways to implement PHP caching, including the following three common ways.

1. File caching

File caching is caching data into a file for future reading. When it's time to read, we can check the file's modification date and, if the file has expired, recreate the file and write new data. Typically, we can use file caching for content that needs to be read quickly but changes infrequently, such as blog posts or announcements for website pages.

The following is a sample code for file caching:

function get_data_from_cache($key, $filename, $time_to_expired = 60) {
    $data = '';
    $path = __DIR__ . '/' . $filename;
    if(file_exists($path) && (time() - filemtime($path)) < $time_to_expired) {
        $data = file_get_contents($path);
    } else {
        $data = get_data_from_database($key);
        file_put_contents($path, $data);
    }
    return $data;
}

2. Memcached caching

Memcached caching is implemented by installing a Memcached server. Data is stored in the Memcached server in the form of key-value pairs. Every time we need to cache data, we can store it in the Memcached server and set an expiration time. When reading data, we can get the data from the Memcached server by key name. If the data has expired, the data needs to be regenerated and stored in the Memcached server.

The following is a sample code for Memcached cache:

$memcache = new Memcached();
$memcache->addServer('localhost', 11211);

function get_data_from_cache($key) {
    global $memcache;
    $data = $memcache->get($key);
    if($data === false) {
        $data = get_data_from_database($key);
        $memcache->add($key, $data, 60);
    }
    return $data;
}

3. Redis cache

Redis cache is implemented by installing a Redis server. Data is stored in the Redis server in the form of key-value pairs. Every time we need to cache data, we can store it in the Redis server and set an expiration time. When reading data, we can get the data from the Redis server by key name. If the data has expired, the data needs to be regenerated and stored in the Redis server.

The following is a sample code for Redis cache:

$redis = new Redis();
$redis->connect('localhost', 6379);

function get_data_from_cache($key) {
    global $redis;
    $data = $redis->get($key);
    if($data === false) {
        $data = get_data_from_database($key);
        $redis->setex($key, 60, $data);
    }
    return $data;
}

5. How to determine the cache expiration time?

The cache expiration time depends on the type of cached data and the update frequency. If the cached data rarely changes, then a longer expiration time can be used. Conversely, if the data changes frequently, a shorter expiration time should be used to ensure that the cached data is up to date.

6. Conclusion

By developing cache in PHP, we can greatly improve the performance of the website and reduce the usage of resources. More importantly, we can also improve the user experience. This article discusses the advantages of caching with PHP and sample code to help web developers optimize their PHP applications and improve their maintainability.

The above is the detailed content of How to improve website maintainability through PHP cache development. For more information, please follow other related articles on the PHP Chinese website!