# Working with on-demand queues
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Your account starts with one on-demand queue, which is the default queue when you create jobs. With on-demand queues, you pay based on usage. For pricing details, see [AWS Elemental MediaConvert pricing](http://www.amazonaws.cn/mediaconvert/pricing/). 

This section describes processing multiple jobs in parallel, creating additional queues, viewing queues, updating queues, pausing or activating queues, and deleting queues.

**Topics**
+ [Processing multiple jobs in parallel](#queue-resources)
+ [Creating a queue](creating-queues.md)
+ [Updating queues](updating-queue-status.md)
+ [Viewing queue details](listing-queues.md)
+ [Deleting a queue](deleting-a-queue.md)

## Processing multiple jobs in parallel
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The total number of jobs that you can process concurrently depends on the following: 

Service quota for **Concurrent jobs per account**  
Your account has a service quota for the maximum number of jobs that MediaConvert can process at one time, across *all* of your on-demand queues in the current Amazon Web Services Region. You can request an increase to this quota by using the [Service Quotas](https://console.amazonaws.cn/servicequotas/home/services/mediaconvert/quotas) console.

Service quota for **Concurrent jobs per on-demand queue**  
Your account has a service quota for the maximum number of concurrent jobs that are available to any *individual* on-demand queue in the current Amazon Web Services Region. You can request an increase to this quota by using the [Service Quotas](https://console.amazonaws.cn/servicequotas/home/services/mediaconvert/quotas) console.

Queue configuration for **Concurrent jobs**  
Each of your on-demand queues has a setting for Concurrent jobs, which is the maximum number of jobs it can process at one time. This setting is constrained by both of the above service quotas. With any individual queue, you can set Concurrent jobs up to your service quota for Concurrent jobs *per on-demand queue*. With multiple on-demand queues, the total number of concurrent jobs combined must also be less than or equal to your service quota for Concurrent jobs *per account*.

When your on-demand queue is running at its maximum concurrent job count and a job completes, MediaConvert selects the next job to process based on the job's *priority*. For more information, see [Setting job priority](setting-the-priority-of-a-job.md).

If a job stays in a `SUBMITTED` state for too long instead of moving to `PROGRESSING`, then your on-demand queue is likely already processing the maximum number of concurrent jobs that it can. To address this, first [check how many unallocated jobs that you have available](listing-queues.md). If you have unallocated jobs available, you can either [increase the Concurrent job count for your queue](updating-queue-status.md), or you can [create a new queue](creating-queues.md). If you don't have unallocated jobs available, you can request an increase to your quotas by using the [Service Quotas](https://console.amazonaws.cn/servicequotas/home/services/mediaconvert/quotas) console.

If you occasionally need to process jobs right away:

1. Use job priority. Submit most of your jobs with a low priority setting, and submit high priority jobs with a higher priority. When you choose this option, you must wait for jobs that are already processing to complete before the higher priority jobs begin. For more information, see [Setting job priority](setting-the-priority-of-a-job.md).

1. Use multiple queues. Submit most of your jobs to a queue with a high concurrent job count, and submit high priority jobs to a different queue with a low concurrent job count. When you choose this option, you keep some transcoding resources idle, but available, until you need them.

You can also organize your jobs with multiple on-demand queues. For example, you might run jobs for different workflows in separate queues. MediaConvert processes these jobs across multiple queues in parallel. You can use [Tags](tagging-mediaconvert-resources.md) to keep track of jobs with different workflows as well.

**Performance testing**  
We recommend that you test any workflow with specific performance requirements. By default, MediaConvert optimizes the performance of your queue for the most common job types. If your workflow primarily includes a large number of jobs that complete quickly, or if you have a question about your queue's performance, contact [Amazon support](https://aws.amazon.com/contact-us/).