Asynchronous IO

[Undercover Agent]

Async reading and writing of files

this is a tracking ticket -- individual tasks depending.

For current computers, IO operations are the most noticeable performance bottleneck -- usage of the very limited IO bandwidth must be carefully managed. By offloading the reading and writing of files to the OS and IO hardware (DMA), we can free computing resources and avoid blocking waits for the persistence operations to complete. However, performing async IO correctly is anything but easy, and there is no universal / portable solution available; some research and experimentation is necessary to arrive at a long term maintainable solution, while achieving good performance on a wide range of systems.