Updated on 2023-07-03 GMT+08:00

Real-Time Synchronization

Precautions

The performance indicators provided in this section are for reference only. The actual environment is affected by factors such as the performance of the source or destination database, network bandwidth, data model, and service model.

Specifications

Based on the performance of data flow types, there are four types of specifications: micro, small, medium, and large. Table 1 lists the performance upper limit of each specification.

Table 1 Performance upper limit

Specifications

Reference Values of Maximum Performance (Rows/Second)

Micro

300

Small

3,000

Medium

7,500

Large

> 7,500

  • The performance of each specification is affected by factors such as the networks, source and destination database performance, and latency. The values in the table are for reference only.
  • DRS measures the performance of different specifications using the full (with flow control disabled) and incremental synchronization tasks as the standard.
  • The maximum performance (row/second) is measured by the number of transactions synchronized per second. The statement types include BEGIN, COMMIT, DML (INSERT, DELETE, and UPDATE), and DDL.
  • Currently, DRS supports specification upgrade only in MySQL-to-MySQL synchronization tasks with single-node DRS instances configured. Task specifications cannot be downgraded. For details, see Changing Specifications.
  • If you want to compare values and the DRS task you create supports value comparison, select a large specification for your DRS instance when creating the DRS task.

Testing Models

Create a full+incremental real-time synchronization task for two RDS for MySQL instances. Table 2 shows the instance configurations.

Table 2 Instance specifications

Parameter

Source RDS for MySQL instance

Destination RDS for MySQL instance

Flavor

c6.4xlarge.4 (general-enhanced II)

c6.4xlarge.4 (general-enhanced II)

Instance specifications

Ultra-high I/O

Ultra-high I/O

Storage type

16 vCPUs|64 GB

16 vCPUs|64 GB

Storage space

300 GB

300 GB

Maximum connections

18,000

18,000

Maximum QPS

3,325

3,325

Maximum IOPS

114,152

114,152

Test model:

  • The number of test tables is 20.
  • All test tables have primary keys.
  • The record size is 1 KB.
  • Each transaction contains two DML operations and one COMMIT operation. The ratio of INSERT, UPDATE, and DELETE operations is 1:1:1.

Multiple Specifications

DRS real-time synchronization allows you to select specifications for some specified data flow tasks, but the specifications cannot be changed after a task is created.

Table 3 Data flow types that support multiple specifications

Synchronization Direction

Data Flow

Multiple Specifications

To the cloud

MySQL->MySQL

Yes

To the cloud

MySQL->PostgreSQL

Yes

To the cloud

MySQL -> GaussDB distributed

No

To the cloud

MySQL -> GaussDB primary/standby

No

To the cloud

MySQL->GaussDB(DWS)

Yes

To the cloud

MySQL->GaussDB(for MySQL)

Yes

To the cloud

PostgreSQL->PostgreSQL

Yes

To the cloud

PostgreSQL->GaussDB(DWS)

No

To the cloud

PostgreSQL -> GaussDB primary/standby

No

To the cloud

PostgreSQL -> GaussDB distributed

No

To the cloud

DDM->MySQL

Yes

To the cloud

DDM->GaussDB(DWS)

Yes

To the cloud

DDM->DDM

Yes

To the cloud

Oracle->GaussDB(DWS)

Yes

To the cloud

Oracle->PostgreSQL

Yes

To the cloud

Oracle->MySQL

Yes

To the cloud

Oracle->GaussDB(for MySQL)

Yes

To the cloud

Oracle -> GaussDB primary/standby

No

To the cloud

Oracle -> GaussDB distributed

No

To the cloud

Oracle->DDM

Yes

To the cloud

DB2 for LUW -> GaussDB primary/standby

No

To the cloud

DB2 for LUW -> GaussDB distributed

No

To the cloud

DB2 for LUW->GaussDB(DWS)

No

To the cloud

TiDB->GaussDB(for MySQL)

No

To the cloud

Microsoft SQL Server->GaussDB(DWS)

No

To the cloud

Microsoft SQL Server -> GaussDB primary/standby

No

To the cloud

Microsoft SQL Server -> GaussDB distributed

No

To the cloud

Microsoft SQL Server->Microsoft SQL Server

No

To the cloud

MongoDB->DDS

No

From the cloud

MySQL->MySQL

Yes

From the cloud

MySQL->Kafka

Yes

From the cloud

MySQL->CSS/ES

Yes

From the cloud

MySQL->Oracle

Yes

From the cloud

DDM->MySQL

Yes

From the cloud

DDM->Oracle

Yes

From the cloud

DDM->Kafka

Yes

From the cloud

DDS->MongoDB

Yes

From the cloud

PostgreSQL->Kafka

Yes

From the cloud

GaussDB primary/standby -> MySQL

No

From the cloud

GaussDB primary/standby -> Oracle

No

From the cloud

GaussDB primary/standby -> Kafka

Yes

From the cloud

GaussDB primary/standby -> GaussDB(DWS)

Yes

From the cloud

GaussDB primary/standby -> GaussDB distributed

No

From the cloud

GaussDB primary/standby -> GaussDB primary/standby

No

From the cloud

GaussDB distributed -> MySQL

No

From the cloud

GaussDB distributed -> Oracle

No

From the cloud

GaussDB distributed -> GaussDB(DWS)

Yes

From the cloud

GaussDB distributed -> Kafka

Yes

From the cloud

GaussDB distributed -> GaussDB distributed

No

From the cloud

GaussDB distributed->GaussDB primary/standby

No

From the cloud

GaussDB(for MySQL)->MySQL

Yes

From the cloud

GaussDB(for MySQL)->GaussDB(DWS)

Yes

From the cloud

GaussDB(for MySQL)->Kafka

Yes

From the cloud

GaussDB(for MySQL)->CSS/ES

Yes

From the cloud

GaussDB(for MySQL)->Oracle

Yes

Self-built -> Self-built

MySQL->Kafka

Yes

Self-built -> Self-built

MySQL->CSS/ES

Yes

Self-built -> Self-built

Oracle->Kafka

Yes

Self-built -> Self-built

Oracle -> GaussDB primary/standby

No

Self-built -> Self-built

Oracle -> GaussDB distributed

No

Self-built -> Self-built

PostgreSQL->Kafka

Yes

Self-built -> Self-built

GaussDB primary/standby -> Oracle

No

Self-built -> Self-built

GaussDB primary/standby -> Kafka

Yes

Self-built -> Self-built

GaussDB distributed -> Oracle

No

Self-built -> Self-built

GaussDB distributed -> Kafka

Yes