What is Memcached? Memcached and Others – 2023

To briefly answer the question of what is Memcached; It is an open source, multi-server, memory-based data caching system. Almost all major platforms such as Facebook, YouTube, Twitter and Reddit use this caching system.

Memcached is used to quickly read, store and call database queries and XML data, especially web applications. It is used by many Web Hosting companies because it offers high performance, especially for high-traffic websites.

What does memcached do?

Since Memcached processes data according to the available memory size, it reduces the burden of databases by making this data accessible quickly. Because of these features;

• YouTube,
• Facebook,
• slashdot,
• wikipedia,
• Sourceforge
• It is preferred on platforms such as Twitter and Reddit.

The largest use of memes in the world is on Facebook. Currently, the company has become one of the official developers of Mem.

guru – user of completeness

Memcached Installation – cPanel

This caching can work in operating systems such as Alma Linux, Rocky Linux, Ubuntu. After making sure that you have installed the package;

apt install -y ea-podman-repo
apt update
apt install -y ea-podman ea-memcached16 

run the code. Then, after logging into SSH as the cPanel user;

/usr/local/cpanel/scripts/ea-podman install ea-memcached16

access the directory. Create a directory with the container name containing the mem socket file;

~/ea-podman.d/container-name/memcached.sock

This socket file is the one you will direct your application to use as the Mem location.

It should be noted that there should not be any authentication/authorization mechanism in MEM in order to avoid performance loss. Anyone who can access the port that the meme server is listening to can also access its content if they know the key name.

guru – user of completeness

Installing Memcached – Debian

Firstly;

sudo apt update
sudo apt install memcached

Enter the above codes into Terminal. Don’t forget to do the following operation as the remote connection must be turned off.

-l 127.0.0.1

It is important to remember that opening it outside for security reasons carries a great risk. If it is to be opened for management purposes, we must whitelist it with a fixed ip and ensure its security.

systemctl restart memcached

Then, with the netstat -tolpn command, make sure that the service is running on port 11211.

root@debian:~# netstat -tolpn
Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address           Foreign Address         State       PID/Program name     Timer
tcp        0      0 127.0.0.1:11211         0.0.0.0:*               LISTEN      21131/memcached      off (0.00/0/0)
tcp        0      0 0.0.0.0:22              0.0.0.0:*               LISTEN      530/sshd             off (0.00/0/0)
tcp        0      0 127.0.0.1:25            0.0.0.0:*               LISTEN      17396/exim4          off (0.00/0/0)
tcp6       0      0 :::22                   :::*                    LISTEN      530/sshd             off (0.00/0/0)
tcp6       0      0 ::1:25                  :::*                    LISTEN      17396/exim4          off (0.00/0/0)

Thanks to Mertcan Gökgöz for the explanation.

What are the Differences Between Memcached and Redis?

Memcached and Redis are two different tools that can be used as data caching systems. However, they both offer different functionality and are optimized for different usage scenarios.

1. Data type support: Redis has wider support for data types and can store data in a variety of ways: string, hash, list, set, chain, bitmap, etc. On the other hand, Memcached only supports data stored as key-value pairs.
2. Persistence: Redis supports persistence of data and makes this data permanent. This ensures that data is protected in case of server shutdown or other loss. Memcached, on the other hand, stores data only in memory and is a system where data is lost when the server is shut down.
3. Replication: Redis supports replication (backup) of data and ensures that this data is backed up on multiple servers. The other is that there is no replication support.
4. Functional features: Redis has additional functional features such as data expiration, pub/sub messaging system, Lua script support. The other does not support such additional functionality.
5. Performance: While both are high-performance tools, Mem optimized for memory-based caching offers the highest performance for key-value data only. Redis, on the other hand, may offer slower performance, although it offers more data type support and functional features.

In general, Mem is suitable for fast and efficient key-value data caching, but Redis is more suitable for users who need more data type support and functional features.

What is Memcached Object Cache?

Memcached Object Cache is a caching system in a web application such as WordPress that allows data from the database to be stored in memory and accessed quickly. WordPress has to pull data from the database as each page loads, but this process is slow and time consuming. At this point, Mem Object Cache comes into play and stores the data pulled from the database in memory. Thus, this data can be accessed quickly on the next page load and page load time can be accelerated.

Also, Mem Object Cache allows data to be synchronized across multiple servers, so changes to the database are instantly visible to all servers. This reduces the load on the database and improves the performance of the application.

Mem Object Cache is a highly recommended caching system for its potential to increase the performance and speed of a web application like WordPress.

If there is no connection test passed (green text) statement, there is no Mem support on your server. Therefore, turning this function on will not work for you to a large extent.

– Dogukan KOZBA

The details of the Litespeed Cache plugin in WordPress are explained in our article titled WordPress Site Acceleration. In connection with this subject; You can also find the answers to the questions of Changing the PHP Version of cPanel and What is Mod Security in our related content.