Why Are Applications Suspended After They Are Moved From Lost_and_Found Queue to Another Queue?

Updated on 2022-02-22 GMT+08:00

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Question

When a queue is deleted when there are applications running in it, these applications are moved to the "lost_and_found" queue. When these applications are moved back to another healthy queue, some tasks are suspended.

Answer

If no label expression is set for the current application, the default label expression of the queue is used as label expression for new container/resource demands requested by the application. If there is no default label expression of the queue, then default label is considered as the label expression for new container/resource demands requested by the application.

When application app1 is submitted to the queue Q1, label1, the default label expression of the queue, is used for the application's new resource requests/ containers. If Q1 is deleted when app1 is running, app1 is moved to the "lost_and_found" queue. Because there is no label expression of the "lost_and_found" queue, default label is used as the label expression of app1's new resource requests/containers. Assume that app1 is moved to another normal queue Q2. If Q2 supports label1 and default label, app1 can run properly. If Q2 does not support label1 or default label, the resource request with label1 or default label cannot obtain resources, causing task suspension.

To solve this problem, ensure that the queue to which the application is moved from "lost_and_found" queue supports label expression of the moved application.

You are not advised to delete a queue in which there are running applications.

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