Poul-Henning Kamp wrote:
If we can increase the tolerance to 10sec, IERS can give us the leapseconds with 20 years notice and only the minority of computers that survive longer than that would need to update the factory installed table of leapseconds.
Rob Seaman replied:
No. Rather all computers that exist during such an event are obligated to deal with it. The number of deployed systems follows some increasing trend similar to Moore's law. By delaying the adjustments, you guarantee that more systems will be affected when they do occur. And, unless you can guarantee that a particular deployed system (and systems derived through various upgrade pathways) will be retired prior to the adopted horizon, prudent policy would require remediation in any event. Would like to see a proposed architecture a little more detailed than a "factory installed table".
PHK can reply for himself here but, for the record, I think RS's reading of what he said is different from mine. My assumption is that PHK is discussing the idea that leaps should be scheduled many years in advance. They should continue to be single second leaps - just many more would be in the schedule pipeline at any given point. Obviously, the leap seconds would be scheduled on the best available estimates but as we don't know the future rotation of the Earth this would necessarily increase the tolerance. In theory DUT1 would be unbounded (as it sort of is already) but PHK is assuming that there'd be some practical likely upper bound such as 10 seconds. Am I right in this reading? Ed.