Instance categories - ApsaraDB for MongoDB - Alibaba Cloud Documentation Center

This topic describes general-purpose and dedicated-disk instance categories of ApsaraDB for MongoDB.

Categories

Instance family	Description	Scenario
General-purposes	General-purpose instances occupy dedicated memory and storage space, and shared CPU and I/O. Therefore, the instances may compete for resources. CPU resources are highly reused among shared instances that are deployed on the same physical server. This maximizes cost-effectiveness.	Price-sensitive scenarios. Scenarios that require a baseline level of performance stability.
Dedicated	Dedicated local-disk instances occupy dedicated memory, storage space, and CPU resources, but share I/O resources. Therefore, the instances may compete for I/O resources. Dedicated cloud-disk instances occupy dedicated memory, storage space, and CPU and I/O resources. Therefore, the instances do not compete for resources. Dedicated cloud-disk instances also provide higher performance stability and is less affected by other instances that are deployed on the same physical server than dedicated local-disk instances. Dedicated-host instances occupy all resources of a host and do not compete for resources.	Business scenarios where databases are used as core systems. The scenarios include providing finance, e-commerce, and large and medium-sized Internet services and handling government affairs.

The following figure shows the differences between general-purpose instances, dedicated local-disk instances, and dedicated cloud-disk instances. 实例规格族

Instance specifications

For more information about instance specifications such as the number of vCPUs, memory, storage capacity, maximum number of connections, and IOPS, see Instance types.

Pricing

For more information about the pricing of each instance type, see Billable items.

Change instance specifications

For more information about how to change the specifications of an instance, see Change the configurations of an instance.