This topic describes the background and features of PolarDB for PostgreSQL Standard Edition. It also explains the differences between the Standard and Enterprise editions and how to purchase a cluster.
What is PolarDB for PostgreSQL Standard Edition
Since its launch, PolarDB has successfully supported thousands of customer applications and demonstrated excellent performance in real-world business scenarios. PolarDB provides an exceptional database experience with its superior performance, high stability, and advanced enterprise-grade features.
Initially, PolarDB targeted large enterprises and customers with demanding requirements by offering only the Enterprise Edition. This edition was built on highly customized physical machines and featured PolarStore, Alibaba Cloud's proprietary distributed storage technology. This configuration ensured maximum performance and stability but at a relatively high cost.
As technology evolved and market demands changed, PolarDB introduced a more cost-effective product version: the Standard Edition. Unlike the Enterprise Edition, the Standard Edition uses standardized, large-scale cloud compute and storage resources. More importantly, the PolarDB team performed deep kernel optimizations to maintain high performance while significantly reducing costs. This not only offers customers a more affordable price but also provides a wider range of flexible compute and storage options through deep integration with products such as ECS and cloud disks. The architecture of the Standard Edition is shown below:
PolarDB for PostgreSQL Standard Edition delivers greater cost-effectiveness. This allows more customers to benefit from the high performance, elasticity, and stability of its cloud-native architecture.
Differences between PolarDB for PostgreSQL Standard Edition and Enterprise Edition
The Enterprise and Standard editions of PolarDB for PostgreSQL share a highly consistent core architecture and feature set. This means you receive the core benefits of PolarDB regardless of which edition you choose. The main difference between the two editions lies in the software and hardware of their compute and storage layers.
In the compute layer, the Enterprise Edition uses physical machines, which eliminates virtualization overhead. The Standard Edition uses ECS servers.
In the storage layer, the Enterprise Edition offers two performance configurations: PSL4 and PSL5. The main difference between these options is their performance metrics, such as input/output operations per second (IOPS) and read/write bandwidth. These metrics are based entirely on the compute node's specifications and are not directly related to the actual storage capacity. This design ensures that Enterprise Edition users receive consistent, predictable high performance at any storage volume.
The Standard Edition offers more flexible storage options. It uses standard cloud disk technology and provides multiple performance options, including PL0, PL1, PL2, PL3, and AutoPL. Unlike the Enterprise Edition, the performance metrics for these options scale with storage capacity. When the data volume is small, the performance is lower at approximately 50 IOPS per GB. As the data volume grows, the storage performance increases accordingly, ensuring a smooth experience for your applications.
Storage and data reliability
The Standard Edition of PolarDB for PostgreSQL uses a shared storage architecture with enterprise SSD (ESSD) cloud disks for its storage layer. ESSD cloud disks use a distributed, multi-replica mechanism to deliver low latency, high performance, durability, and high reliability.
ESSD is a new ultra-high performance cloud disk product from Alibaba Cloud. Based on a next-generation distributed block storage architecture combined with 25 GE networking and RDMA technology, ESSD provides up to 1 million random read/write IOPS per disk and lower single-path latency. ESSD cloud disks are available in the following categories:
PL0 ESSD: An ESSD with performance level (PL) 0.
PL1 ESSD: Compared to PL0, a PL1 ESSD increases IOPS by 5 times and throughput by approximately 2 times.
PL2 ESSD: Compared to PL1, a PL2 ESSD increases IOPS and throughput by approximately 2 times.
PL3 ESSD: Compared to PL2, a PL3 ESSD can increase IOPS by up to 10 times and throughput by up to 5 times. It is suitable for business scenarios that require high concurrent I/O performance and highly stable read/write latency.
ESSD AutoPL disk: Unlike PL0, PL1, PL2, and PL3 disks, IOPS is decoupled from capacity. This allows for flexible configuration and on-demand adjustments, which reduces the total cost of ownership (TCO).
For more information, see ESSD cloud disks.
When a disk runs out of storage space, it becomes locked and read-only.
Data reliability
ESSD cloud disks use a distributed triplicate mechanism to provide 99.9999999% data reliability. Your data is automatically replicated within a zone to prevent data loss from unexpected hardware failures. This protects your business from component failures. For more information, see Cloud disk triplicate technology.
How to purchase or migrate to a Standard Edition cluster
You can purchase a PolarDB for PostgreSQL Standard Edition cluster on the PolarDB purchase page.
If you are new to the Standard Edition, you can try the PolarDB free trial version.
PolarDB provides a Migrate from RDS feature. You can use this feature to migrate data from RDS to PolarDB at no extra cost when you purchase a new cluster.
You can use Data Transmission Service (DTS) to perform an online migration from a self-managed PostgreSQL instance or an RDS instance to PolarDB for PostgreSQL.
You can use the open source `pg_dump` and `pg_restore` tools to perform an offline migration.
Related references
PolarDB official account (Search for "PolarDB" on WeChat)
Customer support email: polardb-pg-support@list.alibaba-inc.com