Well one of the key points is that interrupts (apparently) do not drain currently executing instructions: almost all outstanding isntructions are thrown away, i

Well one of the key points is that interrupts (apparently) do not drain currently executing instructions: almost all outstanding isntructions are thrown away, including already executed but unretired instructions. Only the next to retire instruction is apparently allowed to complete (possibly because interrupts are only checked every time an instruction retires).