When you first encounter LiteSpeed Web Server (LSWS), choosing the right license or even the right LSWS edition can be difficult. This wiki will explain the differences between the different editions and licenses (focusing more on licenses) and go over some ways to help you decide which license is right for you.

There are two different editions of LiteSpeed Web Server. (See the feature comparison on the main site for an in-depth comparison.)

• OpenLiteSpeed: Open source and free. Powerful enough for any website, but does not automatically read and use Apache configurations. Easy to configure (understands Apache mod_rewrite syntax), but requires that you configure it on your own.
• Enterprise Edition: The ultimate combination of power and usability. Even more power and features than OpenLiteSpeed. Faster than any other major web server. Requires almost no setup because it automatically reads and uses your existing Apache configurations (including .htaccess files). Compatible with cPanel, Plesk, DirectAdmin, Interworx, and almost all web applications.

LiteSpeed Web Server Enterprise Edition has many different licenses to choose from. These licenses reflect how much power LiteSpeed Web Server will be given. Generally, the licenses are divided by how many worker processes are spawned, though there are a few, more affordable licenses with domain and RAM limitations.

New Licenses

• Free Starter Licenses: A free license with a 1-domain limit (unlimited subdomains) and 2GB RAM limit. This license spawns one worker process.
• Site Owner Licenses: An affordable option with a 5-domain limit (unlimited subdomains) and an 8GB RAM limit. This license spawns one worker process.
• Site Owner Plus Licenses: This license has a 5-domain limit (unlimited subdomains), but no RAM limit. It spawns one worker process.
• Web Host Lite Licenses: A smart option for those who have multiple domains, but have less than 8GB of RAM. This license spawns one worker process.
• Web Host Essential, Web Host Professional, and Web Host Enterprise Licenses: These license are differentiated by the number of worker processes spawned. They have no domain or RAM limits.
• Web Host Elite: This option is for those who want to be able to configure the number of worker processes. It has no domain or RAM limit.
• LSCache: LiteSpeed Cache, our extremely powerful page caching feature, is bundled free with all licenses.

Notes: Free starter, Site Owner, and Web Host Lite licenses will not install on a server over the licenses' respective RAM limits.

Legacy Licenses

• VPS Licenses: An affordable option for a smaller VPS. The VPS license has a limit of 500 concurrent connections and 2GB RAM. The VPS license has access to one core on your server.
• Ultra VPS Licenses: A solution for VPS users who have between 2GB and 8GB of RAM. The Ultra VPS license has a limit of 800 concurrent connections. VPS users wanting to utilize more than 8GB of RAM will require a 1-CPU license. (The Ultra VPS license is only supported on LiteSpeed Web Server v4.2.2 and up.)
• 1-CPU, 2-CPU, 4-CPU, and 8-CPU Licenses: The number of CPUs in the license title refers to the number of the server's cores that LSWS will be able to make use of. Thus a 1-CPU license will have access to one core, and a 2-CPU license will have access to two cores, etc. Note that you are not required to have LSWS make use of all your server's cores! (See below.) LSWS is fast and lightweight enough to run very, very well on only a fraction of a server's available cores.
• LSCache: LiteSpeed Cache is bundled free with 2-CPU or greater licenses. For all other licenses, LSCache can be bought as a separate module.

Notes: VPS and Ultra VPS licenses will not install on a dedicated server or VPS over the licenses' respective RAM limits. If the concurrent connection limit is surpassed, extra connections will be queued until there is room within the connection limit. Currently supported VPS platforms are KVM, HyperV, Virtuozzo, OpenVZ VPS, XEN, VMWare and UserModeLinux VPS.

VPS or Ultra VPS license can also be used on Amazon (using Xen) and Google Cloud (using KVM) since they support the above virtualization technologies.

Owned License

• One time payment
• One year of free LiteSpeed Web Server updates

(If you would like to update LiteSpeed Web Server to a newer version on your current license after this one year period, you can purchase another year of updates at a discounted price.)

Leased License

• Smaller monthly/yearly payments
• Free LiteSpeed Web Server updates at any time

When choosing between our legacy licenses, you do NOT need to buy a license with a title that matches the number of CPUs or cores on your physical server. The number of CPUs in the license title simply denotes the number of cores that the LSWS process will be allowed to utilize.

LSWS is fast and lightweight enough to run very, very well on only a fraction of a server's available cores. In almost all cases, you are better off buying a license for only a fraction of your server's cores and leaving the other cores available for heavier processes like PHP and MySQL.

Note: Hyper-threads do NOT count towards your core total.

• Have you tried a trial license?

We offer free 15 day trial licenses. These licenses are Web Host Professional licenses. Using a trial license may be a good way to figure out if LSWS is right for you and what type of license you may need.

• You can always upgrade or downgrade.

Often, finding exactly the right license for your usage is a matter of trial and error. Different sites put pressure on different parts of the server. The best approach may be to purchase a license, then try upgrading or downgrading to see if it affects your service noticeably. You can upgrade or downgrade at any time and you will only be charged the difference in the license fee for the remainder of the billing period.

• What other processes are running on the same server?

For example, if you have a 4 core server and run LSWS, PHP, and MySQL on the same server, you will probably be best served by a Web Host Essential or Web Host Professional license. LSWS is light enough that it only needs access to 1 or 2 of this server's cores. PHP and MySQL (which are much more resource intensive than LSWS) will be unaffected by this limit and will have access to all 4 of the server's cores.

• Is the content you serve mainly static (such as images, file downloads, etc.)?

Static content is served by LSWS directly, so assigning it more CPU cores may help with this. If your server is mainly using PHP or MySQL (for instance, if it is running web applications like WordPress, etc.), giving LSWS access to more cores will not help as LSWS is not the bottleneck in these cases.

• Do you have a high volume of HTTPS traffic?

HTTPS requires more CPU power for encryption. You may find that giving LSWS access to more cores in this case will improve performance. Do not overestimate this effect though. Unless your server only serves static HTTPS, LSWS should still only have access to a fraction of the server's cores.

A top command will reveal important information about how much resources different processes are taking on your server. (LSWS's process is called lshttpd.) A couple of these outputs are useful for determining if your installation of LSWS needs access to more cores:

• %CPU - Generally LSWS's CPU usage is low. If LSWS's CPU usage starts climbing, and especially if it climbs while your overall load is low, it can indicate that LSWS is hitting a bottleneck and would benefit from access to more cores.
• %wa - High I/O wait can also be an indicator that LSWS needs more worker processes (and thus access to more cores).

Some editions and licenses have a limit on the maximum number of concurrent connections you can serve. The VPS license has a limit of 500, and Ultra VPS has a limit of 800.

If you've already installed LSWS, you can check the number of concurrent connections in the Real-Time Statistics report in the WebAdmin console.

Even without LSWS you can use the command

netstat -an | grep 80 | grep ESTA | wc -l 

to check your current number of concurrent connections. You may be surprised how few concurrent connections you have. (For example, a forum with 3,000 users online might use 300 concurrent connections or less, as those 3,000 users are not executing actions at the exact same time.)