This topic describes the instance types that are supported by PolarDB-X instances.
PolarDB-X provides the following instance families: general-purpose, dedicated, and dedicated host.
- Dedicated: The computing resources of a server such as CPU cores that are allocated to each PolarDB-X instance are exclusive to the instance. This improves performance stability.
- General-purpose: Idle computing resources such as CPU cores are shared among PolarDB-X instances on the same server. This improves cost-effectiveness.
- Dedicated host: Each PolarDB-X instance exclusively occupies the allocated computing resources, such as CPU cores. Data nodes exclusively occupy the IOPS resources of the entire host.
General-purpose instance family
| Instance family | Instance type | CPU and memory specifications | Maximum storage | Maximum number of connections | Maximum IOPS |
|---|---|---|---|---|---|
| General-purpose | polarx.x4.medium.2e | 2 CPU cores, 8 GB memory | 3072GB | 20000 | 4000 |
| General-purpose | polarx.x4.large.2e | 4 CPU cores, 16 GB memory | 3072GB | 20000 | 7000 |
| General-purpose | polarx.x4.xlarge.2e | 8 CPU cores, 32 GB memory | 3072GB | 20000 | 12000 |
| General-purpose | polarx.x4.2xlarge.2e | 16 CPU cores, 64 GB memory | 3072GB | 20000 | 14000 |
Dedicated instance family
| Instance family | Instance type | CPU and memory specifications | Maximum storage | Maximum number of connections | Maximum IOPS |
|---|---|---|---|---|---|
| Dedicated | polarx.x8.large.2e | 4 CPU cores, 32 GB memory | 3072GB | 20000 | 9000 |
| Dedicated | polarx.x8.xlarge.2e | 8 CPU cores, 64 GB memory | 3072GB | 20000 | 18000 |
| Dedicated | polarx.x8.2xlarge.2e | 16 CPU cores, 128 GB memory | 3072GB | 20000 | 36000 |
| Dedicated | polarx.x8.4xlarge.2e | 32 CPU cores, 128 GB memory | 3072GB | 20000 | 36000 |
| Dedicated | polarx.x8.4xlarge.2e | 32 CPU cores, 256 GB memory | 3072GB | 20000 | 72000 |
Dedicated host instance families
| Instance family | Instance type | CPU and memory specifications | Maximum storage | Maximum number of connections | Maximum IOPS |
|---|---|---|---|---|---|
| Dedicated host | polarx.st.8xlarge.25 | 60 CPU cores, 470 GB memory | 6144GB | 20000 | 120000 |
| Dedicated host | polarx.st.12xlarge.25 | 90 CPU cores, 720 GB memory | 6144GB | 20000 | 140000 |
Description
- Data nodes support the general-purpose, dedicated, and dedicated host instance families. Compute nodes support only the general-purpose and dedicated instance families.
- The instance types that are listed in this topic specify the specifications for single nodes. A PolarDB-X instance consists of at least two nodes to ensure high availability. Each performance and capacity metric of an instance can be calculated based on the following formula: Capacity units of an instance = Capacity unit per node × Number of nodes.
- The instance type that specifies 2 CPU cores and 8 GB memory provides the basic specifications that are required in tests, trials, and light-load scenarios. We recommend that you do not use this instance type in a heavy-load production environment. We recommend that you use a dedicated instance type that specifies 8 CPU cores and 32 GB memory or higher in a production environment.
- When you create a PolarDB-X instance, you can select node specifications for the primary instance. Then, each time you create a read-only instance for the primary instance, the read-only instance uses the same node specifications and contains the same number of nodes as the primary instance by default.
- The maximum number of IOPS is a theoretical value. The maximum number of connections is the maximum number of connections that can be established from applications to each compute node.