I have a new article available on making use of the libevent and libev libraries. libevent has become a very popular choice for people that want to build very efficient I/O systems, particularly for network solutions, and therefore it fits nicely into applications like memcached and lighttpd, both of which make use of the event driven architecture. From the intro:

Building a modern server application requires a method of accepting hundreds, thousands, and even tens of thousands of events simultaneously, whether they are internal requests or network connections effectively handling their operation. There are many solutions available, but the libevent library and libev libraries have both revolutionized the performance and event handling capability. In this article, we will examine the basic structure and methods available for using and deploying these solutions within your UNIX® applications. Both libev and libevent can be used in your high performance applications, including those deployed within the IBM Cloud or Amazon EC2 environment, where you need to support large numbers of simultaneous clients or operations.

Read the article: Boost network performance with libevent and libev