Quotas for Standard Workflows

AWS Step Functions places quotas on the sizes of certain state machine parameters, such as the number of API actions that you can make during a certain time period or the number of state machines that you can define. Although these quotas are designed to prevent a misconfigured state machine from consuming all of the resources of the system, many aren't hard quotas.

Note

If a particular stage of your state machine execution or activity execution takes too long, you can configure a state machine timeout to cause a timeout event.

Quotas Related to State Machine Executions

Quota	Description
Maximum execution time	1 year. If an execution runs for more than the 1-year maximum, it will fail with a States.Timeout error and emit a ExecutionsTimedOut CloudWatch metric.
Maximum execution history size	25,000 events. If the execution history reaches this quota, the execution will fail. To avoid this, see Avoid Reaching the history quota.
Maximum execution idle time	1 year (constrained by the maximum execution time)
Maximum execution history retention time	90 days. After this time, you can no longer retrieve or view the execution history. There is no further quota for the number of closed executions that Step Functions retains.

Quotas Related to Task Executions

Quota	Description
Maximum task execution time	1 year (constrained by the maximum execution time)
Maximum time Step Functions keeps a task in the queue	1 year (constrained by the maximum execution time)
Maximum activity pollers per Amazon Resource Name (ARN)	1,000 pollers calling GetActivityTask per ARN. Exceeding this quota results in this error: "The maximum number of workers concurrently polling for activity tasks has been reached."
Maximum input or output size for a task, state, or execution	262,144 bytes of data as a UTF-8 encoded string. This quota affects tasks (activity, Lambda function, or integrated service), state or execution output, and input data when scheduling a task, entering a state, or starting an execution.

Quotas Related to API Action Throttling

Some Step Functions API actions are throttled using a token bucket scheme to maintain service bandwidth.

Note

Throttling quotas are per account, per AWS Region. AWS Step Functions may increase both the bucket size and refill rate at any time. Do not rely on these throttling rates to limit your costs.

Quotas In US East (N. Virginia), US West (Oregon), and Europe (Ireland)

API Name	Bucket Size	Refill Rate per Second
StartExecution	1,300	300

Quotas In All Other Regions

API Name	Bucket Size	Refill Rate per Second
StartExecution	800	150

Quotas Related to State Throttling

Step Functions state transitions are throttled using a token bucket scheme to maintain service bandwidth.

Note

Throttling on the StateTransition service metric is reported as ExecutionThrottled in Amazon CloudWatch. For more information, see the ExecutionThrottled CloudWatch metric.

Service Metric	Bucket Size	Refill Rate per Second
StateTransition — In US East (N. Virginia), US West (Oregon), and Europe (Ireland)	5,000	1,500
StateTransition — All other regions	800	500

Requesting a Quota Increase

Use the Support Center page in the AWS Management Console to request a quota increase for resources provided by AWS Step Functions on a per-Region basis. For more information, see To Request a Quota Increase in the AWS General Reference.