Comment by exikyut | Hacker News Reader

Comment by exikyut | Hacker News Reader

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That's awesome.

A comment on a recent thread about a train IT failure went on a bit of an interesting tangent about ahead-of-time network scheduling in (IIUC) the Netherlands' TURNI system - https://news.ycombinator.com/item?id=30902585

(The whole thread was a bit of a wide-spectrum ramble, as one might expect for a downtime event.)

So you're saying you were actually doing JIT routing as opposed to AOT? The linked system apparently precomputed the trip<->driver/conductor schedules overnight. I wonder if they're still using that approach today. It does feel like a JIT approach is much more amenable to handling the unpredictable non-spherical real world (eg electricity issues, track breakage, crashes at crossings, train malfunctions that block tracks (right on junctions >:D), etc).

This sorta thing is definitely beyond my own mental level :) but for reference, how would someone interested get their foot in the door in this area?

So we thankfully didn't have to worry about conductor schedules another system our company built did it and we just worked on the assumption that the cow was spherical, this alone made a world of difference in segmenting whose head was exploding at which time.

All the rest was on us, failures, breakages, crashes (We never had one!!!), blocks were super interesting btw!.

So I got on it by chance, I just did interviews as a sport when I was in my early 30's so at some point I passed on this position, pay was awesome, lot's of travel involved, etc... So I joined and learned it all there, it was a small mom and genious software house that specialized on all types of JIT planning for railroads.

JIT was actually "THE" solution to it, because the controllers could just try it during the day, so let's say they new 18:00 was the worst and there was a huge trains comming in at that time with priority, he would just throw shit at the system to see how to same the most time sometimes, of course he knew how to do it by heart, but was it the "Best way" we could help him answering it super fast.

P.S: I am not ducth but I lived there for a while, I remember thinking about how much of a bad day it would have been if it was me, I knew exactly what the NS people were felling :D

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