Counts a failure against the queue head when the fill threw rather than reported.
A throw skips fillOne()'s three-strikes rule and the alarm re-arms in 1 ms (a spin).
fillOne()
the attempts now recorded, or undefined when the queue was empty
Counts a failure against the queue head when the fill threw rather than reported.
A throw skips
fillOne()'s three-strikes rule and the alarm re-arms in 1 ms (a spin).