During a data migration or synchronization task, DTS reads from the source database and writes to the destination database at full speed by default. This can overload either database and degrade application performance. Throttling lets you cap the read and write rates so that migrations run without impacting production workloads.
This topic applies to both data migration and data synchronization tasks.
Prerequisites
Before you begin, ensure that you have:
A data migration or data synchronization task in DTS
Access to the DTS console or DMS console
Limitations
If you modify the objects to be synchronized, subtasks generated after the modification do not inherit the throttling configuration from the full synchronization stage.
Enable throttling
Go to the Data Migration page and select the region where your task resides.
Use one of the following consoles:
DTS console
Log on to the DTS console.
In the left-side navigation pane, click Data Migration.
In the upper-left corner, select the region where your task resides.
DMS console
Note: The steps may vary depending on your DMS console mode and layout. For details, see Simple mode or Customize the layout and style of the DMS console.
Log on to the DMS console.
In the top navigation bar, move the pointer over Data + AI > DTS (DTS) > Data Migration.
From the drop-down list to the right of Data Migration Tasks, select the region where your task resides.
Open the Performance Monitoring tab for your task.
On the Data Migration page, find the task and click its task ID.
(Optional) In the left-side bar, click Task Management. On the Subtask Details tab, click the ID of a subtask.
Note: This step applies only to distributed tasks.
In the left-side bar, click Performance Monitoring.
Enable throttling for the migration phase you want to limit.
Full data migration
On the Performance of Full Data Migration tab, click Enable Throttling for Full Data Migration.
In the Modify the Write Rate of Full Data Migration dialog box, set Enable Throttling for Full Data Migration to Yes.
Review the description of each metric and configure the parameters based on your requirements.
Incremental data migration
On the Performance of Full Data Migration tab, click Enable Throttling for Incremental Data Migration.
In the Modify the Write Rate of Full Data Migration dialog box, set Enable Throttling for Incremental Data Migration to Yes.
Review the description of each metric and configure the parameters based on your requirements.
Click OK.
FAQ
Can I enable throttling for change tracking tasks?
No. The speed of data consumption for change tracking tasks is controlled by the change tracking client, not by DTS.
Why is my source or destination database still under high load after I enable throttling?
Two common causes:
Other workloads on the source database are competing for resources independently of DTS throttling.
The volume of data being migrated or synchronized is large enough that the overall load remains high even at the throttled rate.
How do I disable throttling?
Follow the same procedure and set Enable Throttling for Full Data Migration to No.