Features

Redundant infrastructure—Guarantees delivery of your messages at least once, highly concurrent access to messages, and high availability for sending and retrieving messages

Multiple writers and readers—Multiple parts of your system can send or receive messages at the same time

SQS locks the message during processing, keeping other parts of your system from processing the message simultaneously.

Configurable settings per queue—All of your queues don't have to be exactly alike

For example, one queue can be optimized for messages that require a longer processing time than others.

Variable message size—Your messages can be up to 8 KB in size

For even larger messages, you can store the contents of the message using the Amazon Simple Storage Service (Amazon S3) or Amazon SimpleDB and use Amazon SQS to hold a pointer to the Amazon S3 or Amazon SDB object. Alternately, you can split the larger message into smaller ones.

For more information about the services, go to the Amazon S3 detail page and the Amazon SimpleDB detail page.

Unlimited queues and messages—You can have as many queues and messages in the Amazon SQS system as you want