LiteSpeed Web Server¶
LiteSpeed Web Server Enterprise 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 also.
|Type||Top-Level Domain Limit||Server (VPS) RAM Limit||Worker Processes|
|Site Owner Plus||5||Unlimited||1|
|Web Host Lite||Unlimited||8GB||1|
|Web Host Essential||Unlimited||Unlimited||1|
|Web Host Professional||Unlimited||Unlimited||2|
|Web Host Enterprise||Unlimited||Unlimited||4|
|Web Host Elite||Unlimited||Unlimited||Configurable|
VPS: 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: A solution for VPS users who have between 2GB and 8GB of RAM. The Ultra VPS license has a limit of 800 concurrent connections. (The Ultra VPS license is only supported on LiteSpeed Web Server v4.2.2 and up.)
1-CPU and 8-CPU: 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 8-CPU license will have access to eight cores, etc.
You are not required to have LSWS make use of all your server's cores! LSWS is fast and lightweight enough to run very, very well on only a fraction of a server's available cores.
The licenses will not work on any server with over the licenses' respective RAM and top-level domian 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 licenses can also be used on Amazon (using Xen) and Google Cloud (using KVM) since they support the above virtualization technologies.
How to Choose a License¶
When choosing a license, the most important thing to pay attemtion to is the limits of each one.
If your server (or VPS) has more than 1 domain on it, you need at least the Site Owner license, and if you have more than 5 domains you need at least the Web Host Lite license.
The RAM limit is based on how much RAM is on the server (or VPS) that you want to install LiteSpeed Web Server on. If the server/VPS is over the RAM limit then LiteSpeed Web Server will not work.
What domains are counted toward the domain limit?¶
name.tld that has its own virtual host is counted toward the limit.
What is a worker process?¶
The number of worker processes describes the number of processes that do general server work. Examples of the work done include: routing requests, SSL decryption/encryption, caching, rewriting, etc.
LiteSpeed will fork that number of processes. Each process will utilize a separate core.
We recommend the license have enough worker processes to make use of roughly 25% of your server's cores. You also must adhere to the domain and RAM limits.
Hyper-threads do NOT count towards your core total.
Factors to Consider¶
- 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.
- Have you tried a trial license?
A trial license is the best way to get an idea of what license type is right for you.
Indicators You Need to Upgrade¶
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).