System scaling

Instances

An instance is a server or virtual machine on which the software is running. A system can have either a single instance or multiple instances. Multi-instance systems have a minimum of four instances.

A system with multiple instances maintains higher availability in case of instance failures. Additionally, a system with more instances can run tasks concurrently and can typically process tasks faster than a system with fewer or only one instance.

A multi-instance system has two types of instances: master instances, which run an essential set of services, and non-master instances, which are called workers.

For more information, see Instances.

Services

Each instance runs a configurable set of services, each of which performs a specific function. For example, the Index service handles the indexing of your data.

In a multi-instance system, services can be distributed across all instances in the system. In a single-instance system, that instance runs all services.

For more information, see Service list.