Setting-up long polling in Amazon SQS - Amazon Simple Queue Service
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Setting-up long polling in Amazon SQS

When the wait time for the ReceiveMessage API action is greater than 0, long polling is in effect. The maximum long polling wait time is 20 seconds. Long polling helps reduce the cost of using Amazon SQS by eliminating the number of empty responses (when there are no messages available for a ReceiveMessage request) and false empty responses (when messages are available but aren't included in a response). For more information, see Amazon SQS short and long polling.

For optimal message processing, use the following strategies:

  • In most cases, you can set the ReceiveMessage wait time to 20 seconds. If 20 seconds is too long for your application, set a shorter ReceiveMessage wait time (1 second minimum). If you don't use an Amazon SDK to access Amazon SQS, or if you configure an Amazon SDK to have a shorter wait time, you might have to modify your Amazon SQS client to either allow longer requests or use a shorter wait time for long polling.

  • If you implement long polling for multiple queues, use one thread for each queue instead of a single thread for all queues. Using a single thread for each queue allows your application to process the messages in each of the queues as they become available, while using a single thread for polling multiple queues might cause your application to become unable to process messages available in other queues while the application waits (up to 20 seconds) for the queue which doesn't have any available messages.

Important

To avoid HTTP errors, make sure that the HTTP response timeout for ReceiveMessage requests is longer than the WaitTimeSeconds parameter. For more information, see ReceiveMessage.