Question: Is Memcached distributed?

Answer

Yes, Memcached is a distributed caching system. It allows you to distribute data across multiple servers, which can improve performance and scalability. By using a distributed architecture, Memcached can store more data than could fit on a single machine, and can handle a larger number of requests.

When you add a value to Memcached, it automatically hashes the key to determine which server should store the data. When you retrieve a value, Memcached uses the same hash function to locate the correct server. This means that data is automatically distributed across your cluster of servers without any configuration on your part.

To use Memcached in a distributed mode, you need to run multiple instances of Memcached on different machines, and configure your application to connect to all of them. Memcached clients are available for most programming languages, and they make it easy to connect to a Memcached cluster.

Here's an example of how to use Memcached in PHP:

// Connect to Memcached
$memcached = new Memcached();
$memcached->addServer('server1', 11211);
$memcached->addServer('server2', 11211);

// Store a value
$memcached->set('key', 'value');

// Retrieve a value
$value = $memcached->get('key');

In this example, we're connecting to two Memcached servers ('server1' and 'server2') and storing a value with the key 'key'. When we retrieve the value, Memcached automatically determines which server to query based on the key.