This topic describes the instance types that are supported by PolarDB-X.
PolarDB-X instances are available in two editions: Enterprise Edition and Standard Edition.
- Enterprise Edition: This edition offers distributed clusters that are able to process more data. It
is oriented to enterprise-level business scenarios that require ultra-high concurrency,
complex queries on large volumes of data, and accelerated analysis. This edition can
improve the efficiency of complex queries and report analysis on large amounts of
data.
- Standard Edition: This edition features an architecture of one primary instance, one secondary instance,
and one logger instance. The architecture ensures strong data consistency by synchronizing
data among multiple replicas. This edition provides various specifications and is
cost-effective. It is oriented to online business scenarios that require ultra-high
concurrency, complex queries, and lightweight analysis. It can improve the efficiency
of complex queries, such as multi-table association, aggregation, and sorting, in
online business.
Note The features supported by the Enterprise Edition and the Standard Edition are different.
When you use these two editions, refer to the corresponding documentation based on
the features provided on the console.
The editions provide 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. Only the Enterprise
Edition supports the dedicated host instance family.
General-purpose instance family
Enterprise Edition
Instance family |
Instance type |
CPU and memory specifications |
Maximum storage capacity |
Maximum number of connections |
Maximum IOPS |
General-purpose |
polarx.x4.medium.2e |
2 cores and 8 GB of memory |
3072 GB |
20000 |
4000 |
General-purpose |
polarx.x4.large.2e |
4 cores and 16 GB of memory |
3072 GB |
20000 |
7000 |
General-purpose |
polarx.x4.xlarge.2e |
8 cores and 32 GB of memory |
3072 GB |
20000 |
12000 |
General-purpose |
polarx.x4.2xlarge.2e |
16 cores and 64 GB of memory |
3072 GB |
20000 |
14000 |
Standard Edition
Instance family |
Instance type |
CPU and memory specifications |
Maximum number of connections |
Maximum IOPS |
General-purpose |
mysql.n2.medium.25 |
2 cores and 4 GB of memory |
1200 |
2000 |
General-purpose |
mysql.n4.medium.25 |
2 cores and 8 GB of memory |
2000 |
4000 |
General-purpose |
mysql.n2.large.25 |
4 cores and 8 GB of memory |
2000 |
5000 |
General-purpose |
mysql.n4.large.25 |
4 cores and 16 GB of memory |
4000 |
7000 |
General-purpose |
mysql.n2.xlarge.25 |
8 cores and 16 GB of memory |
4000 |
8000 |
General-purpose |
mysql.n4.xlarge.25 |
8 cores and 32 GB of memory |
8000 |
12000 |
Dedicated instance family
Enterprise Edition
Instance family |
Instance type |
CPU and memory specifications |
Maximum storage capacity |
Maximum number of connections |
Maximum IOPS |
Dedicated |
polarx.x8.large.2e |
4 cores and 32 GB of memory |
3072 GB |
20000 |
9000 |
Dedicated |
polarx.x8.xlarge.2e |
8 cores and 64 GB of memory |
3072 GB |
20000 |
18000 |
Dedicated |
polarx.x8.2xlarge.2e |
16 cores and 128 GB of memory |
3072 GB |
20000 |
36000 |
Dedicated |
polarx.x8.4xlarge.2e |
32 cores and 128 GB of memory |
3072 GB |
20000 |
36000 |
Dedicated |
polarx.x8.4xlarge.2e |
32 cores and 256 GB of memory |
3072 GB |
20000 |
72000 |
Standard Edition
Instance family |
Instance type |
CPU and memory specifications |
Maximum number of connections |
Maximum IOPS |
Dedicated |
mysql.x8.medium.25 |
2 cores and 16 GB of memory |
2500 |
4500 |
Dedicated |
mysql.x4.large.25 |
4 cores and 16 GB of memory |
2500 |
4500 |
Dedicated |
mysql.x8.large.25 |
4 cores and 32 GB of memory |
5000 |
9000 |
Dedicated |
mysql.x4.xlarge.25 |
8 cores and 32 GB of memory |
5000 |
9000 |
Dedicated |
mysql.x8.xlarge.25 |
8 cores and 64 GB of memory |
10000 |
18000 |
Dedicated |
mysql.x4.2xlarge.25 |
16 cores and 64 GB of memory |
10000 |
18000 |
Dedicated host instance family
Enterprise Edition
Instance family |
Instance type |
CPU and memory specifications |
Maximum storage capacity |
Maximum number of connections |
Maximum IOPS |
Dedicated host |
polarx.st.8xlarge.25 |
60 cores and 470 GB of memory |
6144 GB |
20000 |
120000 |
Dedicated host |
polarx.st.12xlarge.25 |
90 cores and 720 GB of memory |
6144 GB |
20000 |
140000 |
Instance types
- 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 cores and 8 GB of 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. In production
environments, we recommend that you use dedicated instances that have at least 8 cores
and 32 GB of memory.
- 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 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. The actual number of connections
supported by a database instance may vary based on your business.