Performance vs. Scalability

Learn about the definitions of performance and scalability - as well as its two types: vertical and horizontal - and understand the difference between them.


The term performance describes the capabilities of a software system, especially when observed under particular conditions. Performance can be defined with non-functional characteristics of a system that can be measured with metrics like response time or throughput.


Scalability describes the ability of a system to utilize additional resources as efficiently as possible to increase capacity. The best case would be a linear relation between resource and capacity increase.

Two types of scalability must be distinguished:

  • Vertical scalability
  • Horizontal scalability

Horizontal scalability is achieved by adding more nodes to a system, such as adding more server instances. Whereas vertical scalability is achieved by adding resources to a single node in a system, such as more CPU power.

Last modified May 25, 2022