PolarDB for MySQL provides four different editions: Cluster Edition, Multi-master Cluster (Database/Table) Edition , Single Node Edition, and X-Engine Edition. Each edition provides different specifications of compute nodes.

Specifications of compute nodes in different editions

The following sections describe the specifications of compute nodes in different PolarDB for MySQL editions:

  • A Cluster Edition or Multi-master Cluster (Database/Table) Edition cluster supports the General-purpose and Dedicated specifications.
    • Dedicated: Computing resources such as CPUs that are allocated to each cluster are exclusive to the cluster. This improves the stability and reliability.
    • General-purpose: Idle computing resources such as CPUs are shared among clusters on the same server for cost-effectiveness.
  • A Single Node Edition cluster uses nodes of the burstable performance type and shares resources in a computing resource pool. This improves resource usage. The Single Node Edition architecture reduces resource costs because no proxy is required.
  • A X-Engine Edition cluster provides a primary node and multiple read-only nodes. The primary node processes read and write requests. The cluster contains at least one read-only node. The cluster supports the Dedicated and General-purpose specifications.
    • Dedicated: Computing resources such as CPUs that are allocated to each cluster are exclusive to the cluster. This improves the stability and reliability.
    • General-purpose: Idle computing resources such as CPUs are shared among clusters on the same server for cost-effectiveness.

Specifications of compute nodes

Edition Node instance type CPU and memory specification Maximum storage capacity Maximum number of connections Maximum number of inodes in a file system1 Maximum number of blktags in a file system2 Internal bandwidth Maximum IOPS of PSL4 Maximum IOPS of PSL5 I/O bandwidth
Multi-master Cluster (Database/Table) Edition (Dedicated) polar.mysql.mmx4.xlarge 8 cores, 32 GB memory 20 TB 10,000 4,194,304 5,242,880 10 Gbps 48,000 96,000 8 Gbps
polar.mysql.mmx8.xlarge 8 cores, 64 GB memory 30 TB 16,000 6,291,456 7,864,320 10 Gbps 54,000 108,000 10 Gbps
polar.mysql.mmx8.2xlarge 16 cores, 128 GB memory 100 TB 32,000 20,971,520 26,214,400 10 Gbps 96,000 192,000 16 Gbps
polar.mysql.mmx8.4xlarge 32 cores, 256 GB memory 100 TB 64,000 20,971,520 26,214,400 10 Gbps 144,000 288,000 24 Gbps
polar.mysql.mmx8.8xlarge 64 cores, 512 GB memory 100 TB 64,000 20,971,520 26,214,400 10 Gbps 144,000 288,000 24 Gbps
polar.mysql.mmx8.12xlarge 88 cores, 710 GB memory 100 TB 100,000 20,971,520 26,214,400 25 Gbps 192,000 384,000 32 Gbps
Multi-master Cluster (Database/Table) Edition (General-purpose) polar.mysql.mmg2.xlarge 8 cores, 16 GB memory 10 TB 6,000 2,097,152 2,621,440 10 Gbps 18,000 36,000 2 Gbps
polar.mysql.mmg4.xlarge 8 cores, 32 GB memory 20 TB 10,000 4,194,304 5,242,880 10 Gbps 27,000 54,000 4 Gbps
polar.mysql.mmg4.2xlarge 16 cores, 64 GB memory 30 TB 16,000 6,291,456 7,864,320 10 Gbps 31,500 63,000 4 Gbps
polar.mysql.mmg4.4xlarge 32 cores, 128 GB memory 60 TB 32,000 12,582,912 15,728,640 10 Gbps 63,000 126,000 8 Gbps
Cluster Edition (Dedicated) polar.mysql.x4.medium 2 cores, 8 GB memory 5 TB 6,000 1,048,576 1,310,720 1 Gbps 6,000 12,000 1 Gbps
polar.mysql.x8.medium 2 cores, 16 GB memory 10 TB 8000 2,097,152 2,621,440 10 Gbps 13,500 27,000 2 Gbps
polar.mysql.x4.large 4 cores, 16 GB memory 10 TB 8,000 2,097,152 2,621,440 10 Gbps 24,000 48,000 4 Gbps
polar.mysql.x8.large 4 cores, 32 GB memory 10 TB 8000 2,097,152 2,621,440 10 Gbps 27,000 54,000 4 Gbps
polar.mysql.x4.xlarge 8 cores, 32 GB memory 20 TB 10,000 4,194,304 5,242,880 10 Gbps 48,000 96,000 8 Gbps
polar.mysql.x8.xlarge 8 cores, 64 GB memory 30 TB 16,000 6,291,456 7,864,320 10 Gbps 54,000 108,000 10 Gbps
polar.mysql.x4.2xlarge 16 cores, 64 GB memory 100 TB 32,000 20,971,520 26,214,400 10 Gbps 96,000 192,000 16 Gbps
polar.mysql.x8.2xlarge 16 cores, 128 GB memory 100 TB 32,000 20,971,520 26,214,400 10 Gbps 96,000 192,000 16 Gbps
polar.mysql.x4.4xlarge 32 cores, 128 GB memory 100 TB 64,000 20,971,520 26,214,400 10 Gbps 144,000 288,000 10 Gbps
polar.mysql.x8.4xlarge 32 cores, 256 GB memory 100 TB 64,000 20,971,520 26,214,400 10 Gbps 144,000 288,000 24 Gbps
polar.mysql.x8.8xlarge 64 cores, 512 GB memory 100 TB 64,000 20,971,520 26,214,400 10 Gbps 144,000 288,000 24 Gbps
polar.mysql.x8.12xlarge 88 cores, 710 GB memory 100 TB 100,000 20,971,520 26,214,400 25 Gbps 192,000 384,000 32 Gbps
Cluster Edition (General-purpose) polar.mysql.g2.medium 2 cores, 4 GB memory 5 TB 1,800 1,048,576 1,310,720 1 Gbps 3,000 6,000 1 Gbps
polar.mysql.g4.medium 2 cores, 8 GB memory 5 TB 2,000 1,048,576 1,310,720 1 Gbps 6,000 12,000 1 Gbps
polar.mysql.g2.large 4 cores, 8 GB memory 10 TB 3,000 2,097,152 2,621,440 10 Gbps 11,250 22,500 2 Gbps
polar.mysql.g4.large 4 cores, 16 GB memory 10 TB 6,000 2,097,152 2,621,440 10 Gbps 15,750 31,500 2 Gbps
polar.mysql.g2.xlarge 8 cores, 16 GB memory 10 TB 6,000 2,097,152 2,621,440 10 Gbps 18,000 36,000 2 Gbps
polar.mysql.g4.xlarge 8 cores, 32 GB memory 20 TB 10,000 4,194,304 5,242,880 10 Gbps 27,000 54,000 4 Gbps
polar.mysql.g4.2xlarge 16 cores, 64 GB memory 30 TB 16,000 6,291,456 7,864,320 10 Gbps 31,500 63,000 4 Gbps
polar.mysql.g6.2xlarge 16 cores, 96 GB memory 30 TB 16,000 6,291,456 7,864,320 10 Gbps 31,500 63,000 8 Gbps
polar.mysql.g8.2xlarge 16 cores, 128 GB memory 30 TB 16,000 6,291,456 7,864,320 10 Gbps 31,500 63,000 8 Gbps
polar.mysql.g4.4xlarge 32 cores, 128 GB memory 100 TB 32,000 20,971,520 26,214,400 10 Gbps 42,000 84,000 8 Gbps
Single Node Edition polar.mysql.s2.large 4 cores, 8 GB memory 5 TB 6,000 1,048,576 1,310,720 1 Gbps 8,000 16,000 1 Gbps
X-Engine Edition (Dedicated) polar.mysql.ax4.large 4 cores, 16 GB memory 200 TB 8,000 41,943,040 52,428,800 10 Gbps 24,000 48,000 4 Gbps
polar.mysql.ax4.xlarge 8 cores, 32 GB memory 200 TB 10,000 41,943,040 52,428,800 10 Gbps 48,000 96,000 8 Gbps
polar.mysql.ax8.xlarge 8 cores, 64 GB memory 200 TB 16,000 41,943,040 52,428,800 10 Gbps 54,000 108,000 10 Gbps
polar.mysql.ax8.2xlarge 16 cores, 128 GB memory 200 TB 32,000 41,943,040 52,428,800 10 Gbps 96,000 192,000 16 Gbps
polar.mysql.ax8.4xlarge 32 cores, 256 GB memory 200 TB 64,000 41,943,040 52,428,800 10 Gbps 144,000 288,000 24 Gbps
polar.mysql.ax8.8xlarge 64 cores, 512 GB memory 200 TB 64,000 41,943,040 52,428,800 10 Gbps 144,000 288,000 24 Gbps
polar.mysql.ax8.12xlarge 88 cores, 710 GB memory 200 TB 100,000 41,943,040 52,428,800 25 Gbps 192,000 384,000 32 Gbps
X-Engine Edition (General-purpose) polar.mysql.ag2.large 4 cores, 8 GB memory 200 TB 3,000 41,943,040 52,428,800 10 Gbps 11,250 22,500 2 Gbps
polar.mysql.ag4.large 4 cores, 16 GB memory 200 TB 6,000 41,943,040 52,428,800 10 Gbps 15,750 31,500 2 Gbps
polar.mysql.ag2.xlarge 8 cores, 16 GB memory 200 TB 6,000 41,943,040 52,428,800 10 Gbps 18,000 36,000 2 Gbps
polar.mysql.ag4.xlarge 8 cores, 32 GB memory 200 TB 10,000 41,943,040 52,428,800 10 Gbps 27,000 54,000 4 Gbps
polar.mysql.ag4.2xlarge 16 cores, 64 GB memory 200 TB 16,000 41,943,040 52,428,800 10 Gbps 31,500 63,000 4 Gbps
polar.mysql.ag4.4xlarge 32 cores, 128 GB memory 200 TB 32,000 41,943,040 52,428,800 10 Gbps 63,000 126,000 8 Gbps

Maximum number of inodes in a file system1 and maximum number of blktags in a file system2:

  • PolarDB uses the self-developed distributed file system of Polar File System (PolarFS) to access underlying storage. Similar to traditional file systems, PolarFS contains inodes and blktags. An inode corresponds to a file. A blktag corresponds to a 4 MB logical space on Elastic Block Storage (EBS). The numbers of inodes and blktags are linearly related to the storage capacity. For example, a 10 TB disk has a maximum of 2,048,000 inodes and 2,560,000 blktags. If the maximum capacity, maximum number of inodes, or maximum number of blktags is reached, you must upgrade the specifications.
  • Conversion of capacity units:
    • 1 TB=1,000 GB
    • 1 GB=1,024 MB
    • 1 MB=1,024 KB
    • 1 KB=1,024 Byte
Note
  • The maximum IOPS is a theoretical value.
  • A PolarDB cluster that has 2 CPU cores and 8 GB of memory is sufficient to provide the basic specifications required in tests, trials, and other light-load scenarios. We recommend that you do not use clusters of these specifications in heavy-load production environments. In production environments, we recommend that you use clusters that have at least 8 CPU cores and 32 GB of memory.
  • Clusters in a global database network (GDN) do not support specifications of 2 cores and 4 GB of memory or 2 cores and 8 GB of memory.
  • You can specify the specifications of the primary node when you create a Cluster Edition Edition cluster. The same node specifications are automatically applied to read-only nodes.
  • The maximum number of connections for a cluster varies based on the node specifications of the cluster. If you add nodes to a cluster, the number of connections to the cluster remains unchanged.