On Wed, May 5, 2021 at 11:34 PM Bakul Shah <ba...@iitbombay.org> wrote:
> > Imagine that the latency between the device detecting a disconnect > signal and a user hitting a disconnect button is D ns while the fire > detection latency is F ns. So if D > F the device would raise the > alarm even if you implement it all in hardware! The only difference > between a Go implementation vs a hardware one is the window size. > If you want to make it minimize it, Go is not the right solution. > For that, in H/W you'd probably *gate* the alarm line to the fire > department with the disconnect signal! But even so there is a small > window. > > There's a more contrived example which takes this argument to the extreme. It illustrates some of the problems. Imagine you had D on Venus, and F on Mars. You receive radio signals on Earth from F and D. Due to planet orbits, this system is in constant motion, so the window constantly changes. It makes it really hard to nail down a good window, though it can be argued we can precompute the position of planets and thus compensate. However, you might have other systems where even the prediction of the window size is impossible. Most computer systems, as Ian writes, exhibit the same window fluctuations at a far smaller scale, seemingly at random. In particular, time is not absolute in computer systems. See e.g., "There is no Now" ( https://queue.acm.org/detail.cfm?id=2745385) by Justin Sheehy for an example. The writing by Sheehy also injects an important point into these discussions: impossibility results. As you add more and more distribution to a system---of which one can argue that a modern multicore system is, in fact, a distributed system---you may end up with FLP or CAP in disguise. Both these results put a wooden stake through the determinism vampire. I don't think it is too far fetched to argue that prioritization, ordering and (non-)determinism are intertwined. -- J. -- You received this message because you are subscribed to the Google Groups "golang-nuts" group. To unsubscribe from this group and stop receiving emails from it, send an email to golang-nuts+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/golang-nuts/CAGrdgiUUQzs%3Dsm-u8cC31Gn0eQ-R9qFeYF12882z7j10MSG7RQ%40mail.gmail.com.
