Interface RateLimitsOrBuilder (2.18.0)

The max burst size. Max burst size limits how fast tasks in queue are processed when many tasks are in the queue and the rate is high. This field allows the queue to have a high rate so processing starts shortly after a task is enqueued, but still limits resource usage when many tasks are enqueued in a short period of time. The token bucket algorithm is used to control the rate of task dispatches. Each queue has a token bucket that holds tokens, up to the maximum specified by max_burst_size. Each time a task is dispatched, a token is removed from the bucket. Tasks will be dispatched until the queue's bucket runs out of tokens. The bucket will be continuously refilled with new tokens based on max_dispatches_per_second. The default value of max_burst_size is picked by Cloud Tasks based on the value of max_dispatches_per_second. The maximum value of max_burst_size is 500. For App Engine queues that were created or updated using queue.yaml/xml, max_burst_size is equal to bucket_size. If UpdateQueue is called on a queue without explicitly setting a value for max_burst_size, max_burst_size value will get updated if UpdateQueue is updating max_dispatches_per_second.

int32 max_burst_size = 2;

The maximum number of concurrent tasks that Cloud Tasks allows to be dispatched for this queue. After this threshold has been reached, Cloud Tasks stops dispatching tasks until the number of concurrent requests decreases. If unspecified when the queue is created, Cloud Tasks will pick the default. The maximum allowed value is 5,000. This field is output only for pull queues and always -1, which indicates no limit. No other queue types can have max_concurrent_tasks set to -1. This field has the same meaning as max_concurrent_requests in queue.yaml/xml.

int32 max_concurrent_tasks = 3;

The maximum rate at which tasks are dispatched from this queue. If unspecified when the queue is created, Cloud Tasks will pick the default.

• For App Engine queues, the maximum allowed value is 500.
• This field is output only for pull queues. In addition to the max_tasks_dispatched_per_second limit, a maximum of 10 QPS of LeaseTasks requests are allowed per pull queue. This field has the same meaning as rate in queue.yaml/xml.

double max_tasks_dispatched_per_second = 1;