Features and Details of LiteSpeed Web Server ( LSWS )

Posted on September 8th, 2016

What is LiteSpeed web server

LiteSpeed is a web server. Its function is to respond to the requests from a client. Both request and the response will be in the HTTP (Hyper Text Transfer Protocol) protocol. The web responses will be files that creates a web page. The common web servers are Apache, IIS, and nginx. The LiteSpeed Web Server (LSWS) is a high-performance Apache drop-in replacement. According to LiteSpeed Technologies Inc., the LiteSpeed Web Server (LSWS) is the 4th most popular web server on the internet and the number one commercial web server. This software is commonly used with control panels and it replaces Apache as the web server. The LSWS was developed by the LiteSpeed Technologies Inc., in New Jersey. The company was founded in 2002 by George Wang.

The LSWS is available for Linux, OS X, Solaris, and FreeBSD operating systems. They claim that LiteSpeed Web Server is an Apache-interchangeable, high performance, secure, easy-to-use web server. The last stable release of this product was 5.0 and it was released in 2015. According to W3Techs, the LiteSpeed Web Server was used by 1.1 % of overall websites in April 2011, 1.5 % of overall websites in May 2012, and 2% of overall websites in May, 2013. There is a full service package called LiteMage. It contains everything needed to LiteSpeed Web Server such as LiteMage Cache, LiteMage Setup service and support for a year. The LiteMage contract costs $2,500.00 per year. However, there are other packages that exist. There is also an open source LiteSpeed Web Server. It is called OpenLiteSpeed. It is licensed under the GNU General Public License version 3. The OpenLiteSpeed versions 1.3.7 and 1.4.4 support HTTP/2 draft 16 (Nov 2014 – June 2015).


The features of LSWS

There are many features for the LiteSpeed Web Server. We are now going to see the principal features of LiteSpeed Web Server.

1) Apache compatibility.

2) Increase in performance and stability.

3) Increase in server security.

4) The LSWS reduces hardware and support costs.


Apache compatibility

The primary and highlighted feature of the LSWS is it’s compatibility with Apache web server. It is compatible with commonly used Apache features such as mod_rewrite, .htaccess file, and mod_security. The web server is able to load Apache configuration files directly and works as a drop-in replacement for Apache with hosting control panels replacing Apache in less than 15 minutes and will cause no downtime. It means there is no need to do any alteration to the configuration or to any codes that may produce a negative impact. The LSWS completely replaces all Apache functions.


Increase in performance and stability

The main strength of the LSWS is it’s performance and stability. The LSWS has a streamlined event- driven architecture and so it ensures better performance with stability. It can serve thousands of clients simultaneously and it consumes less CPU and memory usage. Usually, LSWS serves more users, handles traffic spikes and neutralizes DDOS attacks itself without additional hardware. Apache is process based and LSWS is event-driven which is the main difference between the two. Apache creates new processes to serve every requests which consumes more resources while LSWS serves multiple connections with a few processes.


Asynchronous I/O support   

The Asynchronous I/O support handles performance issues with the I/O operations. There are synchronous and asynchronous I/Os. When a synchronous input/output request is submitted to the operating system, the writing process blocks until the write is complete before continuing processing. For asynchronous input/output, the processing continues while input/output request is submitted and processed. It allows for bypassing the performance issues related to the input/output operations.


Best dynamic content performance

There is a server API called LSAPI for the LSWS. It delivers best dynamic content performance because it is designed for optimized communication between the server and third party applications. The LSAPI is open source. The LSAPI is available for the following third party scripting languages.

1) PHP




PHP suEXEC performance

The PHP LSAPI 6.0 introduced the suEXEC Daemon mode. It is mainly intended for the shared hosting environments. It enables faster and efficient PHP processing in the shared hosting environments. As we know, the suEXEC allows each PHP processes running with the ownership of particular account and not as the webserver user. It allows high protection such that if one account in the server is compromised, PHP scripts from their account will not be able to perform operations on other user’s files. The suEXEC may cause performance issues because it needs to create new processes every time. In LSWS, the suEXEC Daemon mode solves this issue.


The suEXEC Daemon mode

The suEXEC Daemon mode preserves the security of the suEXEC and forks new processes from a constantly running parent process rather than creating a completely new process. So the performance is not affected.


Three different PHP suEXEC setups for different needs and abilities

The LSWS allows three PHP suEXEC setups for different requirements. The three setups and their description are given below.

suEXEC Worker

This is the standard suEXEC PHP with LSAPI. It creates new individual processes when needed. This setup is recommended for shared hosting environments with limited resources that want custom php.ini files.

suEXEC Daemon

In this case, processes are forked from a constantly running parent process rather than creating a completely new process. This setup is intended for shared hosting environments that do not need custom php.ini files.

suEXEC Process Group

This setup is recommended for the shared hosting environments who want to leverage extra RAM into more powerful opcode caching and thus better PHP performance. Here, each user account gets a separate process group with a constantly running parent process which is forking child processes when needed.


Event-Driven Architecture (EDA)

The event-driven architecture is a software architecture pattern. It promotes the production, detection, consumption of reaction to events. An event can be defined as the change in state. When you read a new email in your inbox, the email’s state is changing from ‘Unread’ to ‘Read’. This is called an event. An event driven architecture consists of event creators and event consumers. The creator is the source of the event. The creator only knows the occurrence of an event. The consumers are entities that need to know the event has occurred.


Increase in server security

The LSWS can increase the server security from that of the Apache. The LiteSpeed Web Server is compatible with mod_security and it has a host of built-in anti-DDoS (Distributed Denial of Service) features. The LSWS is also supported on the Atomicorp’s Realtime ModSecurity Rules and the Atomic Secured Linux. The security updates are issued when new attacks are introduced.


The LSWS reduces hardware and support costs

The LSWS reduces hardware and support costs because the license cost of the product is far less than the hardware cost that needs to upgrade a server with Apache to attain the same results. The support cost is also less by switching to LSWS. cPanel is also supported in LSWS.


If you need any further assistance please contact our support department.



Leave a Reply