A very interesting slide deck comparing sync and async IO

[Ola Fosheim Grøstad via Digitalmars-d]

On Friday, 4 March 2016 at 23:26:02 UTC, Chris Wright wrote:
> You can get that control by interacting with the scheduler. 
> Thread schedulers tend to be in the kernel and fiber schedulers 
> tend to be in userspace, so as a practical matter, it should be 
> easier to get that control with fibers.

But in order to get the benefits of hyperthreading you need to 
schedule compatible workloads on the logical pair that shares a 
physical core, so you need to think about scheduling groups of 
workloads/fibers, not individual workloads/fibers.