There are two ways of applying a rate limit using the
Set using the
Clientclass constructor and defaults to 1,000 requests.
Set the argument when using
post()method. If not provided, the default value of 1,000 requests will be used. The method argument will override the argument provided in the
prefetch argument controls the number of in flight requests made by the
method. Using the default value might overload the
Flow especially if the operation characteristics of the
are unknown. Furthermore the Client can send various types of requests which can have varying resource usage in the
For example, a high number of
index requests can contain a large data payload requiring high input/output operation.
This increases CPU consumption and eventually lead to a build up of the requests on the Flow. If the queue of in-flight requests
is already large, a very light weight
search request to return the total number of
Documents in the index might be blocked until the queue of
index requests can be completely processed. To prevent such a scenario,
prefetch value on the
post() method to limit the rate of
requests for expensive operations.
prefetch argument on the
post() method to dynamically increase
Flow responsiveness for customer-facing requests which require faster response times vs. background requests such as cronjobs or
analytics requests which can be processed slowly.
from jina import Client client = Client() # uses the default limit of 1,000 requests search_responses = client.post(...) # sets a hard limit of 5 in flight requests index_responses = client.post(..., prefetch=5)
A global rate limit on the
Gateway can also be set using the prefetch option in the
This argument however serves as a global rate limit and cannot be customized based on the request workload. The
argument for the
Client serves as a class level rate limit for all requests made from the client. The
argument for the
post() method serves as a method level overriding the arguments at the
Client and the