What is Server Load?
Server Load refers to the average amount of processes waiting to be processed by your server’s CPU. The higher the average, the more processes that are waiting to be processed.
In a nutshell, these numbers represent how busy your server is. While everything calculated can be considered a process, for a server serving websites we can assume that it is likely a PHP process. Many of the websites that are in the internet today run off of PHP coding.
For the following example, we’ll take a website that is running WordPress as it’s Content Management Suite (CMS). When the WordPress site is visited by a user, the server processes the PHP code into static content, HTML, and the processed site is delivered to the viewer’s browser. The CPU on your server executes the PHP code.
When a server is considered to have a High Load average, the number of processes need to be processed by the CPU have grown to an amount that is difficult for the CPU to keep under control. The processes are essentially queued for the CPU, which causes delays, essentially slowing down how fast your site is served to the end user.
For example, let’s say your server is not running any caching and you are running a promotion on your website and receive an immediate surge of traffic visiting your website. The CPU has to process all the PHP code for each of those requests to visit your site. For a larger, more robust server, a traffic spike such as this may not slow down how responsive your site is. But for a smaller server, this could be an issue since it may not be powerful enough to keep up with all of the requests coming in.
In such cases, GPU hosting can be a solution to offload specific types of computational tasks, particularly those involving parallel processing, graphics rendering, or even machine learning algorithms. For websites running advanced analytics, data-intensive operations, or dynamic media content (like high-resolution images or videos), a GPU can significantly reduce the load on the CPU. GPUs are designed to handle thousands of simultaneous operations, which can help optimize processes that would otherwise overburden the CPU.
When used in conjunction with the CPU, GPUs can handle specific types of requests—especially those that involve image processing, media streaming, or AI tasks—allowing the CPU to focus on managing PHP code execution and other core server functions. This can lead to faster load times, reduced latency, and the ability to manage traffic surges more effectively.
In addition to a surge in traffic, inefficient PHP code can cause stability issues for your server. It is important to have a trusted developer reviewing the code to make sure it is written efficiently and kept up to date. Keeping your code up to date will help keep your server stable, but it will also ensure that any security holes have been closed. A high number of requests, inefficient coding, and a compromised CMS, can all lead to a spike in Server Load.
You can think of your CPU usage like merging lanes of traffic on a highway. The main highway is your CPU and the cars on it are processes already running. The cars attempting to merge in are new, incoming processes. If there are too many cars on the main highway, the cars merging will get backed up, causing a delay.
Much like the highway, the number of processes that a CPU can handle depends on the number of cores the CPU has. A single lane highway could handle less simultaneous traffic compared to a 4 lane highway. Similarly, a single core server cannot handle as much simultaneous traffic as a 4 core server. As a general rule of thumb, the maximum load that server can handle is equal to the number of cores that it has. A single core server is considered “maxed out” at a load average of 1.00. A quad-core server maxes out at a load average of 4.00. However, higher numbers are achievable and may not indicate that there are any issues.
Next, let’s learn how to find your Server Load and what those numbers mean in our article Checking Server Load in Linux. If you are curious about memory usage, see our article What is Memory Usage?
