1. Business Background Once an enterprise reaches a certain scale, relying entirely on public cloud infrastructure makes IT costs very high. The cost of purchasing physical machines can be amortized over the next 3 to 5 years, and afterwards the machines are not scrapped; instead they continue to serve beyond their planned lifespan.

1. HPA VS KEDA HPA also provides: Elasticity based on custom metrics Scale to Zero Compared with KEDA, these are no longer disadvantages. The real difference is that HPA can only scale using monitoring data, whereas KEDA can scale using many more data sources — queue messages, databases, Redis, and so on, including monitoring data as well.