This topic describes the instance classes of data migration instances and provides performance test results.
Usage notes
The instance classes described in this topic are only for reference and are not used as a criterion for service level agreement (SLA) evaluation.
Data Transmission Service (DTS) can migrate data to the destination instance within seconds. However, migration latency may increase due to various reasons, such as the high workload of the source instance, the low bandwidth of the transmission network, the network latency, and the poor write performance of the destination instance. Therefore, DTS does not guarantee latency in seconds for data migration tasks.
Terms
Term | Description |
Instance class | DTS provides different instance classes. The incremental data migration performance of a data migration instance varies based on the instance class. |
Table quantity | The total number of tables in the test model. |
Record size | The size of each data record that is incrementally migrated. |
RPS | Rows per second (RPS) stands for the rows of data that is incrementally migrated to the destination table per second. For example, if a data migration instance incrementally migrates 5,000 rows of data to the destination table per second, the RPS of the instance is 5,000. |
If an SQL statement contains operations on multiple rows of data, DTS identifies the operations as multiple data records. If you perform INSERT, UPDATE, and DELETE operations on a data record multiple times, DTS also identifies the operations as multiple data records.
DTS identifies each COMMIT operation as a data record.
Instance classes
DTS provides five instance classes for data migration instances: small, medium, large, xlarge, and 2xlarge. The instance class of a data migration instance determines the maximum RPS of the instance. The maximum RPS described in the following table can be reached only if the following requirements are met:
The number of rows that must be migrated from the source instance per second is greater than or equal to the maximum RPS of the data migration instance.
The write performance of the destination instance is high enough to support the maximum RPS of the data migration instance.
The network latency between the DTS server and the source or destination instance is less than 2 milliseconds.
Instance class | Maximum RPS |
small | 2,000 |
medium | 5,000 |
large | 6,000 |
xlarge | 7,000 |
2xlarge | 11,000 |
The actual RPS of a data migration instance varies based on various factors, such as the network environment, the performance of the source and destination instances, and the latency. The maximum RPS listed in the preceding table is only for reference and is not covered by the SLA of DTS.
Test model
Test procedure: Create an incremental data migration task between two ApsaraDB RDS for MySQL instances. Then, perform a stress test on the source ApsaraDB RDS for MySQL instance to view the performance of incremental data migration.
Instance | Configurations | Maximum performance |
Source instance |
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Destination instance |
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Test model:
The table quantity is 20.
Each table has a primary key.
The record size is 1 KB.
Each transaction has an average of two DML operations and one COMMIT operation. The ratio of INSERT, UPDATE, and DELETE operations is 3:1:2.
Test results
Source instance region | Destination instance region | Network latency between instances (milliseconds) | Instance class | RPS |
China (Hangzhou) | China (Hangzhou) | 0.26 | small | 2,566 |
China (Hangzhou) | China (Hangzhou) | 0.26 | medium | 4,726 |
China (Hangzhou) | China (Hangzhou) | 0.26 | large | 6,378 |
China (Hangzhou) | China (Qingdao) | 26 | small | 2,469 |
China (Hangzhou) | China (Qingdao) | 26 | medium | 4,856 |
China (Hangzhou) | China (Qingdao) | 26 | large | 5,439 |
China (Hangzhou) | China (Beijing) | 26 | small | 2,533 |
China (Hangzhou) | China (Beijing) | 26 | medium | 5,038 |
China (Hangzhou) | China (Beijing) | 26 | large | 6,829 |
China (Hangzhou) | US (Silicon Valley) | 175 | small | 1,753 |
China (Hangzhou) | US (Silicon Valley) | 175 | medium | 2,837 |
China (Hangzhou) | US (Silicon Valley) | 175 | large | 3,884 |
Singapore | US (Silicon Valley) | 198 | small | 1,104 |
Singapore | US (Silicon Valley) | 198 | medium | 1,724 |
Singapore | US (Silicon Valley) | 198 | large | 2,256 |
The preceding test results show the maximum performance of data migration instances of different instance classes. The maximum performance cannot be guaranteed in the following cases: The table to be migrated does not have a primary key, the network latency is high, an update hotspot exists, or the source and destination instances have performance bottlenecks.