a Guide to Load Balancing Techniques for Platform Scalability

As businesses increasingly move to a digital-first approach, the need to scale platforms to meet customer demand has never been greater.

But with this comes the challenge of ensuring that your platform can handle the increased load without affecting performance.

Load balancing is a key technique for achieving platform scalability. By distributing traffic evenly across a number of servers, load balancing helps to avoid any one server becoming overloaded and ensures a smooth user experience.

There are a number of different load balancing techniques that can be used, each with its own advantages and disadvantages. Here, we take a look at some of the most popular load balancing techniques to help you choose the right one for your platform.

Round-robin

Round-robin is one of the simplest load balancing techniques. It involves sending requests to servers in a sequential order, with each server receiving the same number of requests over time.

Advantages:

• Simple to set up and manage
• Easy to understand and predict
• No need for specialised hardware

Disadvantages:

• Not suitable for all types of workloads
• Can lead to uneven load distribution if some servers are faster than others

Weighted round-robin

Weighted round-robin is a variation of the standard round-robin technique. With weighted round-robin, servers are assigned a weight based on their capacity. This means that more requests are sent to servers with a higher weight, and less requests are sent to servers with a lower weight.

Advantages:

• More efficient use of resources
• Can be easily adjusted to changing conditions

Disadvantages:

• Can be difficult to set up and manage
• Not suitable for all types of workloads

Least-connected

With least-connected, the load balancer routes requests to the server with the fewest current connections. This technique is often used with web servers as it helps to avoid overloading a server with too many concurrent connections.

Advantages:

• Ensures even load distribution
• Can be easily adjusted to changing conditions

Disadvantages:

• Not suitable for all types of workloads
• Can be difficult to set up and manage

IP hash

IP hash is a technique that uses the client’s IP address to determine which server should handle the request. The load balancer calculates a hash of the IP address and uses this to select the server.

Advantages:

• Ensures that requests from the same client are always sent to the same server
• Can be used to sticky-session

Disadvantages:

• Not suitable for all types of workloads
• Can be difficult to set up and manage

URI hashing

URI hashing is similar to IP hash, but instead of using the client’s IP address, it uses the URI of the request. This technique is often used in load balancing web traffic as it helps to ensure that requests for the same page are always sent to the same server.

Advantages:

• Ensures that requests for the same URI are always sent to the same server
• Can be used to sticky-session

Disadvantages:

• Not suitable for all types of workloads
• Can be difficult to set up and manage

Source IP

With source IP, the load balancer uses the source IP address of the client to select the server. This technique is often used in conjunction with other load balancing techniques, such as round-robin, to ensure that requests are distributed evenly across a number of servers.

Advantages:

• Ensures even load distribution
• Can be used to sticky-session

Disadvantages:

• Not suitable for all types of workloads
• Can be difficult to set up and manage

When choosing a load balancing technique, it’s important to consider the type of workload that you are balancing. Some techniques, such as round-robin, are suitable for all types of workloads, while others, such as IP hash, are more suited to specific types of workloads.