Memcached vs Memcache: Navigating the PHP Memcached Landscape

In the world of PHP, developers often face a dilemma when working with memcached. PHP offers two seemingly separate libraries: memcache and memcached. This article aims to provide clarity and guidance on which library to choose and when.

The Memcache Library

Memcache is a long-standing library in the PHP ecosystem. It has a simpler installation process as it does not require external C/C libraries. It also offers pre-compiled binaries, making it more convenient to install on various operating systems, including Windows. However, memcache offers a limited feature set compared to its newer counterpart.

The Memcached Library

Memcached is a newer client library that was recently released as stable. It is primarily used by digg and boasts a more comprehensive implementation of the memcached protocol. This library provides a significant advantage over memcache, as it includes several key features:

• CAS Tokens: These tokens prevent stale data by verifying that no other processes have updated the data during a specific thread's execution.
• Read-Through Callbacks: This feature greatly simplifies code and reduces execution time.
• getDelayed(): This operation reduces the waiting time for results from the memcached server.
• Binary Protocol: This option speeds up data transfer between the client and the server compared to the ASCII protocol.
• igbinary: Memcached supports igbinary for efficient serialization of complex data.

Which Library Should You Choose?

The choice between memcache and memcached boils down to the specific needs and requirements of your project. If you prioritize ease of installation and prefer a more basic feature set, memcache may be the better option. However, if you value advanced features such as CAS tokens, read-through callbacks, and binary protocol, memcached is the clear choice.

It is worth noting that the memcached library has an external dependency on the libmemcached library. However, this installation process is generally straightforward and should not pose significant problems for developers.

Conclusion

Ultimately, the decision between memcache and memcached depends on the specific requirements of your project. Whether you prefer a simpler installation process or advanced features determines which library ultimately suits your needs.