Waiting for resources - DataWorks - Alibaba Cloud Documentation Center

This topic describes common issues related to waiting for resources.

Why do tasks wait for resources?
Why does a task keep waiting for gateway scheduling resources?
Why does a data integration task remain in a 'wait' status?

Why do tasks wait for resources?

Problem
When a task is submitted to an execution engine, it may need to wait for resources. This can occur in the following situations:
- Waiting for a resource group for scheduling.
- A data integration task is waiting for data integration resources.
- A computing task is waiting for engine computing resources.
Cause
Resource groups have a limited number of available resources. If a task runs for an extended period and does not release its resources, it can prevent other tasks from running. For more information about task dispatching, see DataWorks resource groups.
Solution
Go to Operation Center > Smart Diagnosis. Enter the instance ID to perform an end-to-end analysis of the task. You can view the execution and queuing status of the task and identify which other tasks are occupying resources. This helps you quickly find tasks that are holding resources for an extended period and blocking other tasks. For more information, see Smart Diagnosis.
To view the tasks that are still running when the Running Status of the current job is Waiting For Resources, right-click the instance node that is in the Waiting For Resources state and select Run Diagnostics > Schedule Resource

Why does a task keep waiting for gateway scheduling resources?

Problem
The task log shows that the task is waiting for gateway scheduling resources.
Cause
The number of concurrent tasks in the resource group has reached its limit.
Solution
You can wait for running tasks to finish and release resources, or you can scale out the exclusive resource group for scheduling. You can check the resource information in the following ways.
- Using shared resource groups for scheduling
  - View using Smart Diagnosis
    Go to Operation Center > Smart Diagnosis. Enter the instance ID to perform an end-to-end analysis of the task. You can view the execution and queuing status of the task and identify which other tasks are occupying resources. This helps you quickly find tasks that are holding resources for an extended period and blocking other tasks. For more information, see Smart Diagnosis.
    When the Running Status of the current job is Waiting For Resources, you can right-click its instance node, which is in the Waiting For Resources state, and select Run Diagnostics > Schedule Resource
  - View using the O&M dashboard
    In Operation Center, go to the O&M Dashboard page to view the usage of public resource groups.
    Note
    The peak hours for DataWorks tasks are from 00:00 to 09:00 daily. During this period, public scheduling resources are in high demand, which may cause tasks to wait for resources. To reduce resource contention, you can run scheduling tasks during off-peak hours or add an exclusive resource group for scheduling in the DataWorks console.
- Operation CenterIf you use an exclusive resource group for scheduling, you can view the list of currently running tasks and the resource usage in the DataWorks console or .
  - View using Smart Diagnosis
    Go to Operation Center > Smart Diagnosis. Enter the instance ID to perform an end-to-end analysis of the task. You can view the execution and queuing status of the task and identify which other tasks are occupying resources. This helps you quickly find tasks that are holding resources for an extended period and blocking other tasks. For more information, see Smart Diagnosis.
    When the Running Status of the current job is Waiting For Resources, you can right-click its instance node, which is in the Waiting For Resources state, and select Run Diagnostics > Schedule Resource
  - View using the DataWorks console
    In the navigation pane of the DataWorks console, click Resource Group List. On the Resource Group List page, you can view the resource Usage and click Usage to view information such as Resource Group Information and Resource Usage.
  - View using Resource O&M
    On the Operation Center page, in the left navigation pane, click Resource O&M to view information such as resource utilization.
    Note
    Exclusive resource groups for scheduling with different specifications support different maximum numbers of concurrent instances. For more information, see Billing of subscription exclusive resource groups for scheduling.

Why does a data integration task always show a 'wait' status?

Problem
The data integration task log indicates that the task is in a 'wait' status.
Cause
The number of tasks running on the data integration resource group exceeds the maximum concurrency that the resource group supports. As a result, the task is waiting for data integration execution resources.
Note
If resource usage is high but no tasks are running, or if tasks cannot run even though the number of executable tasks has not reached the resource group's limit, you can contact support.
Solution:
- Check the value of the `concurrent` parameter in the log or task configuration. If the concurrency is set too high, adjust the task concurrency based on the maximum concurrency supported by the resource group and the number of tasks that are currently running.
- If the concurrency setting for a single task exceeds the maximum concurrency supported by the resource group, stop all concurrent tasks, modify the concurrency setting, and then run the task again.
  In Operation Center, click O&M Dashboard in the navigation pane on the left. On the O&M Dashboard page, select the Data integration tab to view the Sync Task Execution Details.
  Note
  Task concurrency must be configured based on the maximum number of concurrent connections supported by the resource group, the data volume of concurrently running tasks, and the concurrency settings of each task.
  A data integration task occupies one scheduling resource. If a task does not complete in a timely manner, it may prevent other tasks from running.
- You can wait for running tasks to finish and release resources, or you can scale out the exclusive resource group for Data Integration. You can check the resource information in the following ways.
  Note
  If a data integration task is waiting for a resource group, see Accelerate or limit the speed of offline sync tasks for possible solutions.
  - View using Smart Diagnosis
    Go to Operation Center > Smart Diagnosis. Enter the instance ID to perform an end-to-end analysis of the task. You can view the execution and queuing status of the task and identify which other tasks are occupying resources. This helps you quickly find tasks that are holding resources for an extended period and blocking other tasks. For more information, see Smart Diagnosis.
    When the Running Status of the current job is Waiting For Resources, you can right-click its instance node, which is in the Waiting For Resources state, and select Run Diagnostics > Schedule Resource
  - View using the DataWorks console
    In the DataWorks consoleResource GroupsResource Group ListUsageUsageResource Group InformationResource Usage, click in the navigation pane on the left. On the page, check the of the resource group. Click the value in the column to view details, such as and .
  - View using Resource O&M
    In Operation Center, click Resource O&M in the navigation pane on the left to view information, such as resource usage and running tasks.
    Note
    Exclusive resource groups for Data Integration with different specifications support different maximum numbers of concurrent instances. For more information, see Billing of subscription exclusive resource groups for Data Integration.