EP47: Frequent Load-balancing Algorithms – by Alex Xu

This week’s system design refresher:

• High 5 Makes use of of Redis (Youtube video)

• Frequent load-balancing algorithms

• Varieties of VPNs

• Potential experiment platform structure

Most individuals suppose Redis is only for caching.

However Redis can achieve this rather more than that. It’s good for:

• Session retailer

• Distributed lock

• Counter

• Charge limiter

• Rating/leaderboard

• and so forth.

On this video, we get insights into how Redis solves attention-grabbing scalability challenges and be taught why it’s a useful gizmo to know nicely in our system design toolset.

The diagram beneath exhibits 6 frequent algorithms.

• Static Algorithms

  1. Spherical robin
     The consumer requests are despatched to totally different service cases in sequential order. The companies are often required to be stateless.

  2. Sticky round-robin
     That is an enchancment of the round-robin algorithm. If Alice’s first request goes to service A, the next requests go to service A as nicely.

  3. Weighted round-robin
     The admin can specify the load for every service. Those with the next weight deal with extra requests than others.

  4. Hash
     This algorithm applies a hash perform on the incoming requests’ IP or URL. The requests are routed to related cases primarily based on the hash perform outcome.

• Dynamic Algorithms

  5. Least connections
     A brand new request is shipped to the service occasion with the least concurrent connections.

  6. Least response time
     A brand new request is shipped to the service occasion with the quickest response time.

👉 Over to you:

1. Which algorithm is hottest?

2. We are able to use different attributes for hashing algorithms. For instance, HTTP header, request kind, consumer kind, and so forth. What attributes have you ever used?

Suppose you…