Systems and methods for storing and transferring message data

Abstract

Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for storing and transferring messages. An example method includes providing a queue having an ordered plurality of storage blocks. Each storage block stores one or more respective messages and is associated with a respective time. The times increase from a block designating a head of the queue to a block designating a tail of the queue. The method also includes reading, by each of a plurality of first sender processes, messages from one or more blocks in the queue beginning at the head of the queue. The read messages are sent, by each of the plurality of first sender processes, to a respective recipient. One or more of the blocks are designated as old when they have associated times that are earlier than a first time. A block is designated as a new head of the queue when the block is associated with a time later than or equal to the first time. One or more of the first sender processes is allowed to read messages from the old blocks until a second time which is later than the first time. One or more of the old blocks are deleted at a time later than or equal to the second time.