Use Memcached caching to improve PHP application performance

Memcached is an open source, high-performance distributed memory object caching system that can be used to reduce database load and speed up the response speed of Internet applications. For PHP applications, the use of Memcached cache can improve program performance and reduce server load.

1. Why caching is needed

In Internet applications, data access is usually very frequent, and database read and write operations are also very time-consuming. And as the number of users increases, the amount of data access will become larger and larger, and the load on the database will become heavier and heavier. In order to reduce the database load and improve application performance, we need to use a caching system.

2. Introduction to Memcached cache

Memcached is a high-performance distributed memory cache system that can store simple key/value data in memory and access it through simple commands . Because it stores data in memory, the access speed is very fast, and because it can be deployed in a distributed manner, it also has good scalability.

3. Steps to use Memcached cache to improve PHP application performance

1. Installation and configuration of Memcached

First you need to install Memcached on the server, you can use yum Or install from source code. After the installation is complete, you need to configure the startup parameters of the Memcached service, such as the listening IP address and port number, etc. You also need to make sure that the PHP Memcached extension is installed and enabled.

2. Connecting to Memcached

In PHP, connecting to Memcached is very simple, just use the constructor of the memcached class. After the connection is successful, you can use the set method to store data into Memcached.

$mem = new Memcached();
$mem->addServer("127.0.0.1", 11211);

3. Read data from Memcached

When you need to read data from Memcached, you can use the get method. If there is no data in the cache, return false.

$data = $mem->get("key");
if($data !== false) {

echo "data from cache";

} else {

echo "data from database";

}

4. Store data in the cache

When the data changes, it needs to be updated in the cache. You can use the set method to store new data in the cache. You can also use the replace method to replace already stored data with new data.

$mem->set("key", $data);

5. Set the cache expiration time

In order to avoid too many Data is backlogged in the cache, and the cache expiration time needs to be set. You can use the set method of the Memcached class to set the expiration time of the data in seconds.

$mem->set("key", $data, 3600);

6. Delete the data in the cache

When no longer needed When you cache data, you can use the delete method of the Memcached class to delete the data in the cache.

$mem->delete("key");

4. Summary

Using Memcached caching can improve PHP application performance and reduce database load. When using Memcached, you need to pay attention to the cache expiration time and the mechanism for updating the cache. You also need to pay attention to the type and size of the data being stored, and ensure that appropriate data structures are used to store the data.

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