A method of providing assured message delivery with low latency and high message throughput, in which a message is stored in non-volatile, low latency memory with associated destination list and other meta data. The message is only removed from this low-latency non-volatile storage when an acknowledgement has been received from each destination indicating that the message has been successfully received, or if the message is in such memory for a period exceeding a time threshold or if memory resources are running low, the message and associated destination list and other meta data is migrated to other persistent storage. The data storage engine can also be used for other high throughput applications.