Friday Facts #361 - Train stop limit, Tips and tricks

[Nosferatu]

I don't get it, is train limit added already in experemental versions?

No. They have not released any experimentals for 1.1 yet.
If you need it now use the mod that was posted one post above your post
(And on page 3)

[AlastarFrost]

I see a few problems with the train stop limit. Not necessarily that it doesn't work, just that it is not as useful as it could be.

Let's look at some scenarios to explain:

1. Stackers
Up until now, you have a setup like this:
Mine1...MineN -> Stacker with capacity (N-X) -> X unload stations.
The unload stations would be for the same smelter. If you replicate the smelter, you would rename the unload stations. Also all the mines have to be numbered.

With the new feature, you could avoid numbering the mines, but you can't avoid numbering the smelters.
The reason is that if you have the stacker capacity on that station, the trains could (and probably would) fill up one stacker and leave the other smelter unserved.
If you reduce the stacker capacity and therefore the trains limit on the unload station, the trains would not dispatch before there is enough room.

The point here is: The second useful trait of stackers is that they allow the trains to dispatch early and wait for service close to the destination, canceling travel times out for the material flow of the serviced station.

The solution: In addition to the train limits, we would need a way to force a "round-robin" like service of all stations sharing the same name.
This would fill up the stackers of replicated smelters (or whatever else) evenly and still allow trains to dispatch early.

I think this is important when you have far away mining posts and travel times are becoming relevant.

2. Long Distance delivery
This is basically the same problem the other way round.

Let's say you have an ammo factory for your far-away outposts. You would have a similar stacker so that the supply trains can make the trip home early. Without a round-robin distribution onto the ammo factories, there is a good chance all the trains would stack in one stacker and the other ammo factory would run full and stop. Reducing the stackers would cause trains to wait very far away from the ammo factory for their turn and block reservations. To keep the material flowing, you would be forced back to the "old way" of numbering the ammo loading stations.

3. The problem with enforcing round-robin
While this solves the above problems if the smelters (or ammo loading stations) are close together and it doesn't matter too much which of the replicated builds a train uses, this gets tricky when some of those are strategically placed on opposite ends of a megabase. Round-robin would force about 50% of the trains to go to the far station and travel through or around the whole base.
In that case you would prefer that they just stay on their side of the map and use shortest-path routing to find the station.

The solution: Allow Stations with the same name to be grouped and round-robin be enabled with a checkbox within the groups you see fit.
Weirdly enough, we are now back to numbering our stations, only that it happens in an extra system. So we can just do that by renaming the stations.
The option to enable and disable round-robin would still be useful.

In conclusion:
I think that the train limit to reach it's full potential needs the option to switch the allocation strategy from the standard router to round-robin for stations with the same name. Extra grouping within stations of the same name seems unnecessary and would only solve edge cases with far too much new logic.

I hope that helps you in your design process.

[c0bRa]

I want the train limit now!!!

it will solve all my problems in my 1.400 train map!

[AndrewIRL]

Idea for a tip:

This is a problem that I had, and saw it in a few streamers that were new to the game — new players don't even consider that it's possible to put productivity modules into labs, or even science packs recipe; even if they are already using them for blue circuits.

Even fewer people realize that you can put modules into rocket silos.

[Nosferatu]

With the new feature, you could avoid numbering the mines, but you can't avoid numbering the smelters.
The reason is that if you have the stacker capacity on that station, the trains could (and probably would) fill up one stacker and leave the other smelter unserved.

I already use the train stop limit for a while thanks to the mod mentioned above. I can assure you the trains pathfinder already does something to avoid that problem:

When the path includes a train currently waiting at a rail signal -> Add a penalty of 100 + 0.1 for every tick the train has already waited.

If you redesign your stackers so that your trains all have to wait in line (not parallel) then this adds a lot of penalty to your already full station.
--> Trains will tend to go to the other stations...

Additionally I usually use this:

When the rail block is guarded by a rail signal set to red by the circuit network -> Add a penalty of 1000.

When my stacker is nearly full or if all chests in my smelter station are nearly full I switch a signal red by circuit.
This sends out a very clear message to all arriving trains: Go somewhere else

[pleegwat]

Round robin seems like a very bad idea if you have both producers and consumers of the good spread across the map, as it would cause trains to visit far-away stations because it is 'their turn' rather than preferring close ones, causing more material to be in transit and more network congestion.

If you consistently have full stackers, your train stop limit on the associated station is probably too high. If the train stop limit is 3, and 3 trains are en-route, then the 4th train heading for that named stop will not go park in that stops stacker, but look for a different stop or stay at the producer station.

If one stop is being consistently starved of resources, then probably you either don't have enough production or not enough trains.

[alarig]

their screenshots show them combining the output of a line of boilers and sending that output to a line of engines. I'm not quite sure when it would be a good time to have players dip their toe into the depth that is pipe throughput limits

I think that a tip/tuto about the pipes throughput limits. It’s very hard to predict how much L/s we loose per pipe.

[Shingen]

Just have a fuel train that drops fuel off at every station

yeah... that's one of the workarounds that i don't like. and one that is not even possible in some cases.

If it is possible to route the train to a fueling station, then how can it be impossible to send fuel to a station on the train's route?

well, then it's not exactly dropping off fuel at every station.
if you want to keep a rail grid-style base there's no space for a coal drop-off at every station sometimes, or if you worked around it, it would make the cell smaller which is usually a nuisance.
and in your case, again with a rail grid, that destroys the grid idea of transporting resources between cells only with trains.

[NotRexButCaesar]

I don't get it, is train limit added already in experemental versions?

There are experimental 1.1 versions that only the devs have.

[SLB]

I hope GOOGLE Translator can correctly let you understand what I mean...

I don’t think you really understand what the problem is with the train system
The new option trains limit at the station did not solve the problem

Assuming that the stations at both ends of the line can operate at full speed
What determines the number of trains on a route is the length of the route

The longer the length of the line, the longer the train will spend running on the line, and the more trains are needed to ensure that the stations at both ends can operate at full speed.

Unfortunately, as the scale of production capacity increases, the more ore you need, the farther and farther your mine will be.
In addition, the old mines continue to be abandoned after being dug, and your line will become longer and longer.

At the same time you will expand your furnace, repair furnaces in different places, which will also cause changes in the length of the line

What follows is that the number of trains you need is not fixed, but will increase to maintain the same ore supply speed in your factory.

So trains limit did not solve the problem
Because the upper limit of the number of trains is not a fixed value, but is related to the length of the line from this station to the furnace.
Unless our circuit has a way to get the length of the line

[NotRexButCaesar]

I hope GOOGLE Translator can correctly let you understand what I mean...

I don’t think you really understand what the problem is with the train system
The new option trains limit at the station did not solve the problem

Assuming that the stations at both ends of the line can operate at full speed
What determines the number of trains on a route is the length of the route

The longer the length of the line, the longer the train will spend running on the line, and the more trains are needed to ensure that the stations at both ends can operate at full speed.

Unfortunately, as the scale of production capacity increases, the more ore you need, the farther and farther your mine will be.
In addition, the old mines continue to be abandoned after being dug, and your line will become longer and longer.

At the same time you will expand your furnace, repair furnaces in different places, which will also cause changes in the length of the line

What follows is that the number of trains you need is not fixed, but will increase to maintain the same ore supply speed in your factory.

So trains limit did not solve the problem
Because the upper limit of the number of trains is not a fixed value, but is related to the length of the line from this station to the furnace.
Unless our circuit has a way to get the length of the line

What about all cases other than ore>smelting, where distances are fixed.

I’m not sure you understand what problem they were trying to fix: this prevents trains from waiting on the main line and clogging the rails and lets you spread out your trains among stations.

[SLB]

What about all cases other than ore>smelting, where distances are fixed.

I’m not sure you understand what problem they were trying to fix: this prevents trains from waiting on the main line and clogging the rails and lets you spread out your trains among stations.

I understand the problem they want to solve and there is a solution in the current version, but the explanation is more complicated, that is, this problem can be partially solved by guiding the station and the parking station (at least before your FPS is too low to bear)

But the point is not here
The point is that the station system with the same name is designed for a scalable factory. Once the factory starts to expand, the line length is no longer fixed.

[mmmPI]

What follows is that the number of trains you need is not fixed, but will increase to maintain the same ore supply speed in your factory.

So trains limit did not solve the problem
Because the upper limit of the number of trains is not a fixed value, but is related to the length of the line from this station to the furnace.
Unless our circuit has a way to get the length of the line

You think of optimization, having the perfect number of train, not too many , not too few right ?

The train limit help remove the problems of having too many trains.

This means for players it is easier to go above the perfect number of trains. Let say you need 5, 15 or 20, and you have 50.

All excess train will not be running around creating traffic jam. they will wait for an outpost to accept them.You need to think of a place for them to wait.(stacker/parking near main base).

The line lengh for 1 outpost and main base is fixed, so you can estimate/calculate how many trains are required for that 1 outpost. let say 5. Then build stacker for 5 trains near outpost. and set limit of incoming train to 5. This way if you don't look at it and outpost run dry, you will only have 5 train waiting in stacker. If not they will be distributed on the road. no excess train dispatched can block the main line.

Without limit, if the outpost run dry, but is close to main base, potentially all trains for that ressource would wait there instead of only 5.

You can set limit of train individually per outpost when building them. So a far away outpost may require a limit of 10. If you have 50 trains, only 5/50 will try to path to oupost 1, and 10/50 to outpost 2. All other 35/50 trains will be stuck with "destination full". You choose where they stop.

You can try even more adapting setup. If you make an outpost reduce the limit based on train frequency. If a train wait at the oupost for 1 minute, this means outpost is running low on ore, you can use circuit to make a clock, and reduce the limit from 5 to 4 or even 1. This way when outpost run dry, at first all 5 trains waits. But then only 1 at a time will be dispatched there. The other will join the 35/50 trains.


The alternative would be to limit incoming trains to main base, in this case all excess trains need room to wait near outpost. And you can increase the limit if main base is not supplied enough.(possible with circuit) You would also need to increase parking area near main base accordingly, in case you stop consuming ressource.

[SLB]

https://drive.google.com/file/d/1W7rH9s ... sp=sharing
Here is the archive of my last play
There is my solution in it, as I said above, it’s enough before the UPS drops to an unbearable level.
Sorry I can't explain this in English, it's a bit complicated
The unnamed station in front of each station is the so-called guide station. It will be named only when necessary.

What I mean is that the problem that the trains limit can solve can actually be solved in the current version, but the trains limit can't solve the problem of essentially increasing the number of trains as the length of the line becomes longer.
Unless there is some way to get the length of the circuit

[mmmPI]

Sorry I can't explain this in English, it's a bit complicated
The unnamed station in front of each station is the so-called guide station. It will be named only when necessary.

What I mean is that the problem that the trains limit can solve can actually be solved in the current version, but the trains limit can't solve the problem of essentially increasing the number of trains as the length of the line becomes longer.
Unless there is some way to get the length of the circuit

It's VERY complicated i understand you don't explain in english x)

UPS were already low in my old computer , it makes it unpleasant to explore the map.
I saw guide station named " _ ", for all the other station, my chinese lvl is 0, i only guess material thanks to the colors.

Maybe you solve the problem, i don't understand your map

Your central train depot is a sign you found success (i think) but at the cost of LOTS of circuits and combinators.
Your case is special because you don't have a 'main base' that need supply, but instead several module. Outpost name AND module name are generic. this is extra difficulty.


If you are ok with (very) complex design, there may be a way to get the lengh of the circuit. It requires a dummy train dedicated to make measure. You can "read train id" and count times between 2 detection of this useless train. Then divide by speed. Maybe have this train do periodic check to include traffic congestion and update the time. It is only approximation but maybe it could provide enough data to get results. (like knowing approximatively when distance double, triple ,quadruple and so on ).

Also I think you will find a way to use the new limit to simplify your design, or to use other logic to manage train maybe based on that limit.

(also totally unrelated, you have 2 nuclear reactors that miss an inserter for outputing used cell in the southern nuclear plant)

[SLB]

It's VERY complicated i understand you don't explain in english x)

UPS were already low in my old computer , it makes it unpleasant to explore the map.
I saw guide station named " _ ", for all the other station, my chinese lvl is 0, i only guess material thanks to the colors.

Maybe you solve the problem, i don't understand your map

Your central train depot is a sign you found success (i think) but at the cost of LOTS of circuits and combinators.
Your case is special because you don't have a 'main base' that need supply, but instead several module. Outpost name AND module name are generic. this is extra difficulty.


If you are ok with (very) complex design, there may be a way to get the lengh of the circuit. It requires a dummy train dedicated to make measure. You can "read train id" and count times between 2 detection of this useless train. Then divide by speed. Maybe have this train do periodic check to include traffic congestion and update the time. It is only approximation but maybe it could provide enough data to get results. (like knowing approximatively when distance double, triple ,quadruple and so on ).

Also I think you will find a way to use the new limit to simplify your design, or to use other logic to manage train maybe based on that limit.

(also totally unrelated, you have 2 nuclear reactors that miss an inserter for outputing used cell in the southern nuclear plant)

Okay, I didn’t build the nuclear power plant. I didn’t design anything related to nuclear power. Someone built it when I was online.

Let me try to explain this railway system
The unloading station for transporting copper, iron, coal and stone is so complicated because of the mixed unloading.

Basically, you can try to see the main line transporting uranium ore as a starting point
For the part we discussed, the principle of this ore station is the same (of course because there are fewer trains for this ore, I did not build an additional parking station for it. You can pretend that the parking station exists, and the design of the parking station for other ore is the same)
Each ore uses a different train, which is clearly separated


There are 4 types of stations in the system (I mean these 4 types of stations correspond to each ore)

1. LoadStation: When the station box is not enough to fill a train, it will be closed. It will not open until it is enough to fill X cars. When the station is open, it will send a uranium ore signal to the main signal circuit (green line).

2. UnloadStation: When the box in front of the station (green box) is almost full, the station will be closed and will not reopen until the box is almost empty, and will send a uranium ore signal to the main signal circuit (red line) when the station is open

3. ParkingStation: When at least one of the red and green signal circuits does not receive a uranium ore signal, the station will open until a train stops. When the red and green signal circuits have a uranium signal, the station sends a departure signal to the train in the station. And close this site

4. Guide(load or unload)Station: The "_" you see before LoadStation and UnloadStation will use the same signal to control the synchronization switch with the LoadStation and UnloadStation.

Basic train schedule:
LoadStation> ParkingStation> UnloadStation
(ParkingStation is usually closed so there will be no train detours)

When the scale of the railway is expanded to the point where it is necessary to depart from various stations to various stations
You can name the GuideStation as A1 B1 C1 D1...a1 b1 c1 d1...
Then change the schedule of some trains to look like:
A1> LoadStation> ParkingStation> a1> UnloadStation

Among them, A1 and a1 are both far away stations, and trains are less willing to go
This will ensure that the trains will not all go to the nearest available station
And the operation of adding A1 to the train schedule is simple enough, because only adding stations does not need to set any departure conditions. GuideStation is just a checkpoint.

You mentioned above using a dummy train to actually measure the length of the line
This will lead to inaccurate conclusions under heavy traffic, because waiting at intersections will greatly extend the arrival time
If the trains limit of nearby stations is increased due to the extension of the arrival time, the traffic conditions in the vicinity will be worsened and the arrival time will be further extended.
This is a vicious circle

Considering the expansion of the factory and the fact that the circuit cannot accurately obtain the line length data
The actual effect of trains limit is very limited
When this setting is set, as the length of the line increases, the number of restricted trains will not be enough to enable the stations at both ends of the line to load and unload at full speed. This may result in insufficient supply of raw materials or products that cannot be shipped in time in the factory area behind the station
Finally, you still need to change it manually to increase this value
When the scale of the factory becomes larger and the line becomes longer, it is difficult to determine the value at a glance.

[SLB]

I think there is a relatively simple way to solve this problem

trains limit should not be set on the station but on the train

In this way, when the pathfinder is working, the distance from the train to the destination station must be known at this time.

[mmmPI]

You mentioned above using a dummy train to actually measure the length of the line
This will lead to inaccurate conclusions under heavy traffic, because waiting at intersections will greatly extend the arrival time
If the trains limit of nearby stations is increased due to the extension of the arrival time, the traffic conditions in the vicinity will be worsened and the arrival time will be further extended.
This is a vicious circle

True, but you could also measure how much fuel the train has left when it arrive, by trying to add some more. And then calculate how much time the train was waiting and how much time it was rolling and add a condition for increasing limit; (very) complex

Considering the expansion of the factory and the fact that the circuit cannot accurately obtain the line length data
The actual effect of trains limit is very limited
When this setting is set, as the length of the line increases, the number of restricted trains will not be enough to enable the stations at both ends of the line to load and unload at full speed. This may result in insufficient supply of raw materials or products that cannot be shipped in time in the factory area behind the station
Finally, you still need to change it manually to increase this value
When the scale of the factory becomes larger and the line becomes longer, it is difficult to determine the value at a glance.

the effect is limited with your configuration, for many players it will allow them to do new things (making it easy/accessible for more person). This is why i said you could probably change your train logic management to take advantage of the new tool with few tweaks.


the distances between 1 outpost and 1 hub is fixed.
the distance between the hub and a module is fixed.

This means when you expand for ressource you configure the limit for each new outpost based on the distance relative to the hub.
and when you expand production you configure the limit for each new module of production based on the distance to the hub.
in the 2 case you add semi-precise number of new trains to the network, and prepare an area for them to park if not needed.

( area can be near the hub, empty train wait for outpost to accept them; and full train wait for production area to need them ;only correct amount are sent ).

You already have a central depot , which is (over)complex . It will be easier to make one after the change using the limit train logic . And instead of a train depot, it could be a train hub. Difference is that it's not the same train that goes from outpost to hub and from hub to production area. (what you do in your map )

Your system i do not understand everything, i will take more time when i can for this. there are many combinators used for other thing than train logic, and it is hard to recognize in game you describe about train on the forum. I think with your explanation i understand the principle/concept. but the implementation is complex for me. following the wires to understand where signals come from and why is good time, and take long . ( now at least i know what i'm looking at ! thank you for explaining !)

I understand your "guide" station and what you use them for. I have used similar logic in the past using the term "waypoint". it make sense now.

[Laramy65]

Idea for a tip:

This is a problem that I had, and saw it in a few streamers that were new to the game — new players don't even consider that it's possible to put productivity modules into labs, or even science packs recipe; even if they are already using them for blue circuits.

Indeed, I never though about that, thanks a lot for the tip!

What you can and cannot use productivity on always been arbitrary. It makes perfect sense that you cannot use them to empty barrels or in enrichment, but arguably if science packs are intermediate products, science produced in a lab is not. It would be straightforwarder if you could use modules everywhere except forementioned examples, and have those examples be specified in a tool tip. Or say nothing and have modules be insertable and do nothing letting player discover on their own, that ye, they do have thought about infinite fluid duplicator, kinda obvio

[Unknow0059]

But the graph shows a rolling average and not "precise numbers" in the first place. The game doesn't measure how long it takes to produce an item. If you produce one item then there's a 1-tick spike of producing 1 item in a 5 second interval. So the average of that is gonna be weird. "23.8" is probably just the mathematically lowest number that such a 1 second spike produces, that doesn't mean the numbers are imprecise or uncorrect. It can definetly show lower values in the other time scales. If you made a factory that produces exactly 1 item per second forever than i'm guessing it would show correctly on the higher timescales.

Also the 12/m in your screenshot is what i'd call precise: If you produce 1 / 5s then you produce 12 / 60s. Aaand if you think the graph really is wrong then like i said - search the bug forum and if there's nothing similar file a precise bug report.

Even if the graph is technically not wrong, it's not useful to have one single item be represented as 23.8 or whatever, instead of just 1, which is what I expected, since I am in the graph for the 5 second timescale and I've produced a single item in that time.
I'm curious as to how this graph works exactly, in regards to the "rolling average" and how it depends on what the factory produced of that item across its life (according to the text in bold, if I interpreted it correctly) instead of just depending on the chosen timescale.

But those are two tangents. What I originally asked is for the graph to be explained in-game, because it's unclear, and I really wanna know if the graph's average value can be trusted in higher time scales.
If I'm producing 100 of an item every 5 seconds, how do I know the value displayed in the graph would not be off, seeing as it is indeed off in the lower timescales? Maybe it would show me an arbitrary number like 10.3 or something that's completely off from the reality?

I know the "12/m" is accurate - it is what one would expect and can be used to check against the value in the graph.
But it uses the minute unit, not 5 second unit. What if I wanted to know how many items I produced in that time frame? I would have to calculate it manually because what's shown is what I produce per minute, regardless of the timescale I chose. And it's also not a graph.

This is just really confusing.