PolarDB:What is PolarDB for Xscale?

Introduction

PolarDB-X is a cloud-based high-performance distributed database service that is independently developed by Alibaba Cloud. PolarDB-X can provide high throughput, large storage capacity, low latency, high scalability, and high availability to meet business requirements in the cloud era.

PolarDB-X has supported all business of Alibaba Group during Double 11 Shopping Festivals each year. The features provided by PolarDB-X have been developed based on more than a decade of experience. PolarDB-X ensures strong data consistency and provides stable systems and auto scaling of clusters. PolarDB-X is widely adopted in institutions and public sectors, such as justice, finance and taxation, transport logistics, and electric power.

PolarDB-X focuses on developing distributed databases that are compatible with the open source MySQL ecosystem and can be independently managed. PolarDB-X provides easy-to-use databases to help you reduce use costs.

Features

PolarDB-X provides a standard cloud database service in 13 regions worldwide. PolarDB-X uses cloud resources and allows you to deploy databases in containers. This way, you can create a cluster or modify the configuration of a cluster in minutes without manual operations. PolarDB-X also supports the pay-as-you-go billing method to help you reduce costs.

Alibaba Cloud and the open source community provide round-the-clock support for PolarDB-X. PolarDB-X can be used together with a wide range of tools and services in the Alibaba Cloud ecosystem, such as Data Transmission Service (DTS), Database Backup Service (DBS), Data Management (DMS), Database Autonomy Service (DAS), Data Integration, CloudMonitor, and Performance Testing.

PolarDB-X offers compatibility with and contributes to the MySQL ecosystem. PolarDB-X is fully compatible with MySQL protocols, syntax, transaction behavior, account systems, and CLI tools.

PolarDB-X uses a shared-nothing system architecture to decouple storage and computing resources. This aims to maximize the effect of the auto scaling capabilities of cloud databases. In this architecture, you can plan storage capacity based on business requirements.

Data nodes in PolarDB-X are deployed across zones and use a three-node architecture. Data nodes use X-DB databases that are developed by Alibaba Group for storage. This ensures strong consistency between nodes. X-DB uses the InnoDB engine and is fully compatible with MySQL syntax. X-DB can process complex queries. PolarDB-X works together with X-DB to provide a cost-based optimizer (CBO) for hybrid transaction/analytical processing (HTAP). This helps push down calculation processes and improves overall performance.

PolarDB-X aims to provide distributed databases that can be managed as easily as standalone MySQL databases. PolarDB-X provides an easy-to-use distributed database solution. The distributed architecture is transparent to users.

By default, PolarDB-X uses a primary key for sharding. This way, you do not need to specify a partition key when you migrate business data to PolarDB-X.

PolarDB-X ensures high performance and strong consistency for distributed transactions. PolarDB-X uses the self-developed X-Paxos protocol to achieve a zero recovery point objective (RPO) during a failover. PolarDB-X uses the Timestamp Oracle (TSO) policy and the multiversion concurrency control (MVCC) method to isolate resources and ensure consistency between distributed transactions.

PolarDB-X supports linear scaling of distributed databases and uses consistent hashing for partitioning. To reduce hotspotting and implement load balancing, PolarDB-X can offload requests from nodes under heavy load. During a scale-out, PolarDB-X pushes down calculation processes and ensures data consistency. The scale-out of a PolarDB-X instance does not affect your business.

PolarDB-X provides binary logging to resolve the issues of data forwarding from compute nodes to data nodes in distributed databases. In distributed databases, if you restore nodes based on backup files that are created at different points in time, data inconsistency can occur. To resolve this issue, PolarDB-X ensures data consistency before backup and creates backup files based on the globally consistent data.

PolarDB-X provides multiple deployment modes to meet the business requirements for different industries. You can deploy a database instance on Alibaba Cloud or Apsara Stack. PolarDB-X also supports DBStack.

• Alibaba Cloud supports fast iteration of PolarDB-X and ensures stable running of PolarDB-X instances. You can deploy PolarDB-X instances on Alibaba Cloud in fully managed mode. PolarDB-X provides a high-performance cloud native database service in 13 regions worldwide.
• Apsara Stack supports core cloud services that are developed by Alibaba Group and meets compliance requirements for security and isolation.
  Note PolarDB-X Lite on Alibaba Cloud and Apsara Stack can vary based on types of deployment resources.
• DBStack is a lightweight platform for database management and supports core Alibaba Cloud services. DBStack meets the business requirements for high-performance, high-availability, and cost-effective database solutions in diverse scenarios.