VietMX Staff asked 3 years ago
The biggest drawback of using the round robin algorithm in load balancing is that the algorithm assumes that servers are similar enough to handle equivalent loads. If certain servers have more CPU, RAM, or other specifications, the algorithm has no way to distribute more requests to these servers. As a result, servers with less capacity may overload and fail more quickly while capacity on other servers lie idle.
The weighted round robin load balancing algorithm allows site administrators to assign weights to each server based on criteria like traffic-handling capacity. Servers with higher weights receive a higher proportion of client requests. For a simplified example, assume that an enterprise has a cluster of three servers:
- Server A can handle 15 requests per second, on average
- Server B can handle 10 requests per second, on average
- Server C can handle 5 requests per second, on average
Next, assume that the load balancer receives 6 requests.
- 3 requests are sent to Server A
- 2 requests are sent to Server B
- 1 request is sent to Server C.
In this manner, the weighted round robin algorithm distributes the load according to each server’s capacity.
