Platform For AI:Scheduling policies

Background information

If you run multiple jobs at the same time in Platform for AI (PAI), the jobs are submitted to a job queue and processed in a specific order. To optimize the allocation of computing resources within a job queue, PAI provides multiple scheduling policies that you can use to dequeue and process the jobs in an efficient manner. You can configure and manage the scheduling policies on the Resource Quota page in the PAI console. If you modify the scheduling policy of a resource quota after you create the quota, only jobs that have not started running are affected.

Scheduling policies

The following sections describe the content of each scheduling policy provided by PAI.

First In, First Out (FIFO)

If the first job in the queue cannot be dequeued, the system does not skip the job and repeatedly attempts to dequeue the job.

Round Robin

If the first job in the queue cannot be dequeued, the system skips the job and attempts to deque other jobs in the queue in sequence.

Balance

• If the first job in the queue cannot be dequeued, the system does not skip the job and repeatedly attempts to dequeue the job.

• If the first job fails to be dequeued within the predefined duration (a few minutes in most cases), the system attempts to dequeue the first and second jobs by using the Round Robin policy.

• If the second job fails to be dequeued within the predefined duration, the system attempts to dequeue the first, second, and third jobs by using the Round Robin policy. The system dequeues the remaining jobs in the same manner.

Intelligent

The system adopts a scheduling policy based on the priority that you assign to each job.

• Jobs that have a priority greater than or equal to 7 are scheduled by using the FIFO policy.

• Jobs that have a priority less than 7 are scheduled by using the Robin Round policy. In this case, the priority of the jobs in the queue increases by 1 based on their queue time until the priority reaches 6.

In the preceding figure, Item1 and Item2 are assigned a priority greater than or equal to 7, and Items 3 to N are assigned a priority less than 7.

References

For information about how to configure a scheduling policy when you create a resource quota, see Overview.