Having the correct caching mechanisms installed is highly important when it comes to speeding up the overall delivery of the assets on your website. Caching makes sure these assets have been stored closer to users in order for the latency that is incurred from a distance is lowered.
If you are looking into the available options for the right caching system, the chances are high that you have already heard about Memcached. Below we will explain more about what Memcached is along with how it operates in order to increase the speed of dynamic-based web applications.
What Is Memcached?
Memcached is classified as a type of open-source “distributed memory caching” system. This application is useful for speeding up any dynamic-web applications in the way of lowering the database load. To explain this further, each time database requests are made it will add loads into the overall server. Memcached works on decreasing these loads in the way of storing these data objects inside the dynamic memory. Memcached will store any data according to key-values for objects or smaller arbitrary strings which includes:
– Page rendering
– API calls
– Results of the database calls
Memcached consists of 4 main components. It is these components that allow the server and user to deliver the cached data in the most efficient way possible. Here is the list of these 4 components:
– Client Software- Provides the list of the available Memcached servers
– Client-based Hashing Algorithm- Allows the user to select a server according to the “key”
– Server Software- stores the values along with their keys in an Internal-Hash table
– LRU- will decide when to reuse memory or discard of old data
How Does Memcached Work?
As we explained above, Memcached is made up of 4 primary components, and it is those components that allow this system to retrieve and store data. Every item is made up of the following: a key, raw data, and an expiration time. The high-level Memcached will work in the following way:
– The user will request an item of data that Memcached will then check to establish whether this data has been stored in a cache.
– From here there are 2 possible outcomes:
1. If this data has already been stored in a cache: the data is returned from Memcached (which means there is no requirement to check on the database).
2. If this data has been found to not be stored in the cache: the database is then queried, the data is retrieved and then stored in Memcached.
– Whenever any information changes or when the item expires, Memcached will update its cache in order to make sure only fresh content will be delivered to users.
The general setup involves several Memcached servers along with many clients. The clients will use the hashing algorithm in order to decide on which Memcached storage server should be used, which ultimately assists with distributing the load. The server will then compute another or 2nd hash of this key to determine where it needs to be store a corresponding value in the Internal-Hash table.