Memcached System Architecture
Since you’re here, we’re sure you’ve heard about Memcached before and if you haven’t don’t worry because we’ve got you covered. Our article gives a refresher about what is Memcached as well as Memcached Architecture. Read on as we continue to discuss Memcached!
Simply put, Memcached is known as a memory caching system that is used for general purposes. However, users of Memcached typically make use of its capabilities by using it to significantly increase the speed of websites that run on databases. In essence these websites are left in the hands of data caching as well as other objects which are placed into RAM in order to reduce the initial amount of external read data. And, Memcached is a completely free open-sourced software which runs on Microsoft Windows as well as Linux and OS.
Memcached architecture makes use of its client servers. However, the server used holds the associated stored key-values as clients populate and query them by key. In some cases, stored keys can be either 250 bytes or then can be somewhat bigger by being at a maximum of 1Mb. When the servers are contacted by client sided libraries, their initial service is said to be exposed at the port of 11211.
However, Memcached has been designed to readily support both UDP and TCP and each client is said to know all the servers associated. This just simply means that since servers don’t actively communicate with other servers, clients will need to know the servers that they want to contact via Memcached. And if clients or potential clients wish to either read or even set certain key values, their libraries will firstly need to calculate the key hash.
When the hash is calculated, it goes on to determine the correct server to be used. And it also provides the simplest form when it comes to sharding as well as scalable architecture among all servers involved. Additionally, for the sake of storage and even reading abilities, the server computes the second key hash. The values calculated is typically stored on RAM until further use.
In some cases, if a server runs out of RAM, it simply begins to recycle. This just means that it erases the oldest calculated values and begins to put newer ones in its place. So, if a client should ever need old values again, they can simply store it elsewhere. Older values can be stored on other databases such as the Couchbase Server or MemcachedDB.
Memcached was designed with the possibility of using it on a single unit or simultaneously. Hash tables are often rather large and span to more than one system. Memcached can be useful for a variety of situations and circumstances alike. One particular instance being when content generation is high as well as when a specific piece of content costs a lot to generate.
As we conclude we have just given you a refresher on what is Memcached as well as how the systems architecture works. Memcached was designed to facilitate several tasks according to its users. And it can be quite useful when necessary!