LiteSpeed is an information technology company, founded in 2002, that produces web server software that is specifically designed for high-traffic servers, like the ones for Internet service providers and corporate data centers.
LiteSpeed Web Server is the company’s main product. It is a lightweight proprietary web server, which is able to read Apache configurations directly. The software is commonly used together with web hosting control panels, where it replaces Apache as the web server. LiteSpeed Web Server is available for Linux, Mac OS X, Solaris and FreeBSD.
In May 2013, W3Techs reported that LiteSpeed was being used by 1.9% of all websites, making it the 4th most popular web server. This number was up from 1.5% in May 2012 and 1.1% in April 2011.
LiteSpeed Web Server has grown in popularity because it offers superior performance in both raw speed and scalability. It is six times faster than Apache. LiteSpeed also surpasses other well known content accelerators including thttpd, boa and TUX.
LiteSpeed Web Server 5.0
LiteSpeed Web Server 5.0 introduced ESI support. ESI, or Edge Side Includes, is a markup language that allows the user to break a page of dynamic content up into sections which can be served differently. Specifically, ESI allows for partial page caching so that parts of a page generated by a web application can be cached even it other parts of the page can’t. This improves web application performance by allowing for greater cache use.
With 5.0, the web server added a CPU Affinity setting, which binds a process to one or more CPUs. It is better for a process to always use the same CPU because then the process can make use of data left in CPU cache. If the process moves to a different CPU, there is no use of CPU cache and unnecessary overhead is required. The new CPU Affinity setting allows you to control how many CPUs your LiteSpeed Web Server processes will be bound to.