FIFO loading

[Rob]

Hmm, not many seem to have tried this.
But it's working very well, no strange things that I noticed. And the fifo is actually working when there isn't enough cargo at the station waiting to fill all the trains.

Oh and I didn't run in the 255 related limitation, yet.

[DaleStan]

The impfifo branch has been merged; the new nightly builds (r1100 and later) will contain this FIFO system instead of the old one.

[Dave]

Will any change of patch setting be required, DaleStan?

[Lakie]

Just wondering... (Quoted from IRC)

Code: Select all

<Lakie> Given the following suitation...
<Lakie> We have Station Z which has 400 units of goods
<Lakie> We have 2 trains going to start loading a Station Z (Trains X and Y)
<Lakie> Train X (first one) reserves 200 units and starts loading
<Lakie> Now can Train Y (which is identical in capacity) reserve remaining cargo and start loading at the same time too?
<Lakie> Or say there was 300 units of cargo or something at Z, atleast that way, it's still fifo but it still means trains can load if there are large amounts of cargo to be processed?
<Lakie> Or would that be too complex?

Hopefully that happens, or atleast I believe Fifo loading should behave something like that.
Although, I'll leave DaleStan to decide about what happens with Fifo.

I just believe that reserving cargo for the first train doesn't mean no loading of other trains at the same time, if there is excess cargo.

Just my comments on this,
~ Lakie

[Patchman]

Hopefully that happens, or atleast I believe Fifo loading should behave something like that.

That's exactly how it works, Lakie. First train reserves as much cargo as is needed to fill it up, then the second train reserves the rest, etc. and both are loading at the same time.

[DaleStan]

In the first case (400 units at the station), yes. All wagons in both trains immediately begin loading.

In the second case (300 units at the station), we also need to know the capacity of each wagon. For the sake of convince, let's say that there are 10 wagons, each carrying 20 units. Then, all 10 wagons in train X begin loading, as do the first 5 wagons in train Y. Once another 20 units arrive at the station, the next wagon in Y begins loading, and so on. When train X becomes full and leaves, all remaining wagons in train Y, if any, begin loading.

In other words, at least one full consist will always be loading, plus as many more vehicles as can load without the total remaining capacity exceeding the cargo available at the station.

[gmyx]

I seem to be having a problem with FIFO. Using r1100. None of the trains are loading cargo after a few days, even after Cht: ResetFifo. They just do nothing.

Also, I keep getting "New Waddington now accepts passengers" news item every few game days - even thought that station is for several farms without a town in sight AND does not actually accept passengers. Just wait until aprox feb 15 and you'll get the news item.

BTW: Thanks for making this change to FIFO - it will help greatly to prevent deadlocks in stations.

[MJS]

Is Fifo as useful for passengers as it is for cargo? I know passenger behaviour is not realistic anyway (who would want to catch any train from Paris, no matter where it went? Well, there's a few places I'd like to get away from no matter in which direction...), but would it be possible to have a parameter with the fifoload to enable it for all cargoes, or for all cargoes except passengers & mail?

[DaleStan]

The parameter is, as before, the Full load order. Don't set full load, and FIFO won't do anything.

Supposedly, that is; I obviously broke something.

[MJS]

Aha. That makes sense, the Full Load option.

But I now have a passenger train that's set to Full Load, and it insists on loading waggon by waggon, instead of spreading passengers as it used to do. Maybe that's what you were referring too as well, I don't know.

[DaleStan]

gmyx: I believe I've found and fixed the problem; vehicles were leaving that had not arrived. The next nightly should fix this problem.

Attached is a fixed savegame.

MJS: I suspect you have the same problem as gmyx. CHT: ResetFIFO should do the trick starting next nighty; if it doesn't, let me know.

[MeusH]

In the second case (300 units at the station), we also need to know the capacity of each wagon. For the sake of convince, let's say that there are 10 wagons, each carrying 20 units. Then, all 10 wagons in train X begin loading, as do the first 5 wagons in train Y. Once another 20 units arrive at the station, the next wagon in Y begins loading, and so on. When train X becomes full and leaves, all remaining wagons in train Y, if any, begin loading.

Recently NewGRF sets contain wagons of various eras, each with different capacity.
Let's say there is a train A with 20 wagons of capacity=10 units, and a train B with 10 wagons, each carrying 20 units.
Following your alghoritm: Once 10 units arrive at the station, the next wagon in A begins loading.
This way, train B won't be loaded simultanously to train A.
A will load first, leave the station, and eventually let train B load.

Is that right? Or you have some special-case handling?

[Patchman]

A will load first, leave the station, and eventually let train B load.

That's why it's called FIFO loading. Train A will always finish loading first, but if there's enough cargo to fully load train A, then train B will start loading the remaining cargo.

[DaleStan]

So, in both cases, the first train to arrive, plus the front half of the second train, will start loading immediately. The remainder of the second train will start loading as the necessary cargo arrives (I'm assuming you're talking about the 300-unit case here.)

Please explain what part of this paragraph you are not understanding, and I'll attempt to word it better:

In other words, at least one full consist will always be loading, plus as many more vehicles as can load without the total remaining capacity exceeding the cargo available at the station.

[MeusH]

Oh, excuse me, but I thought about sitiuation of no cargo waiting at the station and I didn't mention it.

Let's discuss about two cases:
1) Train A with 10units/wagon gets to a station first. Train B with 20units/wagon gets there second:
I assume that train A will get loaded first.

But onto the second case:
2) Train B with 20units/wagon gets to a station first. Train A with 10units/wagon gets there second:
Train B should have higher priority, but Once 10 units arrive at the station, the next wagon in A begins loading., train A will get served first, won't it?

[Patchman]

The train that gets there first will get loaded first. What's so hard to understand about that?

Capacity makes no difference to loading order, only to how many trains will load simultaneously.

[MeusH]

Okay, thanks

[gmyx]

Again with another FIFO problem. This time it's with an oil field on the left-left of the map. I normaly raise the land near the oil field and use a regular train station. The problem I have is my oil trains are only loading their first wagon - and only one train will do so. All other oil fields on the map are fine. Using r1159

[stevenh]

Could these trains have been sitting there for a while? (ie. if they had broken in a previous beta, they'll still be stuck now, afaik)
Maybe you need one more "cht:resetfifo" on the station just to repair the loading.

[gmyx]

Could these trains have been sitting there for a while? (ie. if they had broken in a previous beta, they'll still be stuck now, afaik)
Maybe you need one more "cht:resetfifo" on the station just to repair the loading.

Actually, I just expanded to it, if you look at my previous save game it was not there. If I do a resetfifo, they load properly one time only. When they return, same problem of only one wagon on one train.