performance issues-MT is almost unplayable

[Unacceptium_core]

i have this weird performance issue recently. i tried downgrading my mods, as i though one of them had a big update, tried reinstalling, updating, downgrading MT itself, the ram cannot be an issue, it says at least 300mb free at top usage, i tried specific settings in MT but nothing.
video showing the issue
the map is in my signature, the tested MT versions are 5.8,5.9,5.10DEV with same results.
the image below is only for seeing how many people view this topic without response.

[Desour]

You're saying, a 14 min long video of you playing is showing how minetest is unplayable???

[Unacceptium_core]

You're saying, a 14 min long video of you playing is showing how minetest is unplayable???

are you understanding what im talking about? the video is for showing what behaviour i am experiencing and hopefully this can help in finding what can be the problem, like if anyone did experience this type of lag before -and yes, this IS a 14 MINUTE VIDEO of MINETEST being UNPLAYABLE. and you are not forced to be here, or watch it, or comment at all. so???

why i made the video? because i am not a programmmer, i have no idea how to solve this kind of problem??? and taking that almost all of this forum's tags is a programmer, i hope(d) that someone knows why is this can be??????? and i can put a lot of questionmarks too????

[yw05]

video showing the issue

Can you narrow this down to driving trains? If yes then this is very likely an issue with the HUD being updated every step, which is quite a bad idea ...

Edit: I assume you are playing on a server? If yes, could you please ask the server admin to apply https://lists.sr.ht/~gpcf/advtrains-devel/patches/55027 and see if things improve?

[Desour]

You're saying, a 14 min long video of you playing is showing how minetest is unplayable???

are you understanding what im talking about? the video is for showing what behaviour i am experiencing and hopefully this can help in finding what can be the problem, like if anyone did experience this type of lag before -and yes, this IS a 14 MINUTE VIDEO of MINETEST being UNPLAYABLE. and you are not forced to be here, or watch it, or comment at all. so???

why i made the video? because i am not a programmmer, i have no idea how to solve this kind of problem??? and taking that almost all of this forum's tags is a programmer, i hope(d) that someone knows why is this can be??????? and i can put a lot of questionmarks too????

Need more escalation!
You did want responses, and even put an image there to count people, right?
If there's just a long video without any explanation what you think is wrong there, you won't get useful responses. Especially if there's nothing unusual in the video, it's jUST YOu playing the game, sO it's noT uNplayable! It's a clickbait title!!!!

[Astrobe]

Chill a bit, Desour. While I understand why you are irritated by the title, the video appears to show some "rubberbanding" (at least in the first few minutes I watched).

There are improvements in 5.9 regarding rubberbanding when the player is attached to something, but in my experience, it is not entirely solved, even at slow speed (like ~3 m/s). I suspect it still happens when the engine is loading blocks, if the backend is slow (Sqilte on a spinning disk...). If it's online play, then of course server and/or network issues are the usual culprits.

PS: OP, your "views tracking" image is (excuse me) a stupid idea. This community started with a bunch of friends trying C55's game; that's not how you treat friends. This forum shows the number of views for each topic, by the way.

[LMD]

the image below is only for seeing how many people view this topic without response

I'm not sure what this is supposed to achieve to be honest. There is no obligation for people to respond to this topic; there may be many curious lurkers.

It is also perfectly acceptable for developers to ignore this thread because they have better things to do; "It's hard to say why exactly this is and I don't really feel like digging into this right now" would not be a useful reply.

[Unacceptium_core]

video showing the issue

Can you narrow this down to driving trains? If yes then this is very likely an issue with the HUD being updated every step, which is quite a bad idea ...

Edit: I assume you are playing on a server? If yes, could you please ask the server admin to apply https://lists.sr.ht/~gpcf/advtrains-devel/patches/55027 and see if things improve?

yes, this only happens when i drive trains, but this did not happen before.
i am playing in singleplayer. i don't know how to apply pqtches and such to mods in mt, but i will give it a try. also thanks for replying lime a human, unlike ↓

You're saying, a 14 min long video of you playing is showing how minetest is unplayable???

are you understanding what im talking about? the video is for showing what behaviour i am experiencing and hopefully this can help in finding what can be the problem, like if anyone did experience this type of lag before -and yes, this IS a 14 MINUTE VIDEO of MINETEST being UNPLAYABLE. and you are not forced to be here, or watch it, or comment at all. so???

why i made the video? because i am not a programmmer, i have no idea how to solve this kind of problem??? and taking that almost all of this forum's tags is a programmer, i hope(d) that someone knows why is this can be??????? and i can put a lot of questionmarks too????

Need more escalation!
You did want responses, and even put an image there to count people, right?
If there's just a long video without any explanation what you think is wrong there, you won't get useful responses. Especially if there's nothing unusual in the video, it's jUST YOu playing the game, sO it's noT uNplayable! It's a clickbait title!!!!

yes, because a lot of you hate android players, thats why i added the image to count. I HAVE NO IDEA whats wrong. and it is unplayable in this state, do you think i'm enjoying playing it like this?
also can you just stop this like yes, i sound like i dont want responses, i'm introvert, accept it or good bye but if you reply, please at least be useful.

Chill a bit, Desour. While I understand why you are irritated by the title, the video appears to show some "rubberbanding" (at least in the first few minutes I watched).

There are improvements in 5.9 regarding rubberbanding when the player is attached to something, but in my experience, it is not entirely solved, even at slow speed (like ~3 m/s). I suspect it still happens when the engine is loading blocks, if the backend is slow (Sqilte on a spinning disk...). If it's online play, then of course server and/or network issues are the usual culprits.

PS: OP, your "views tracking" image is (excuse me) a stupid idea. This community started with a bunch of friends trying C55's game; that's not how you treat friends. This forum shows the number of views for each topic, by the way.

as i wrote, i experience this in 5.9 and 5.10dev too. it does not look like that rubberbanding did the problem.
i'm on a completely usual mobile device, and as i wrote above, i never experienced this, but tbh it did happen for short minutes but rarely.

i cannot find the view counter. maybe my browser renders incorrectly, maybe i just didnt search enough?
keep in mind that i am newly into MT because i cannot afford MC. so mt is free, and theres this forums, with devs and players so even if i dont have friends i can ask for help about the game i think

the image below is only for seeing how many people view this topic without response

I'm not sure what this is supposed to achieve to be honest. There is no obligation for people to respond to this topic; there may be many curious lurkers.

It is also perfectly acceptable for developers to ignore this thread because they have better things to do; "It's hard to say why exactly this is and I don't really feel like digging into this right now" would not be a useful reply.

okay. this topic meant to get some of my questions solved. and yes, this topic is targeting mostly players, who did experience this. but at least you responded like a human so thanks at all.

but my problem is that this is a new performance issue, i never experienced it this commonly and this long, and also please accept that no one is perfect, theres people like me who are less than an actual game developer.

EDIT
i have tried the patch, i manually added the new code. did not solve anything.
some "news" for those who actually wants to help:
after leavong the train, the game progress will be unsaved. the problem seems to be caused by advtrains. wherever the train goes in an infinitely reversing accelerating state-happens when stopping in this laggy state-the maps loads new chunks.

i found the view counter. it is only shown if the device is in landscape or desktop mode. it does not show when the device is in portrait mode.

[Nininik]

i have a similar issue in singleplayer in my testing world, somehow exploring and making new terrain for testing some cave stuff LAGS AS HELL on android

[Astrobe]

FWIW, on PC there's an advanced parameter for which the default value is detrimental for my old machine; "mapblock mesh generation delay" (just search "mesh" with "advanced settings" ticked). It causes an FPS drop when you keep moving, and also affects mapblock loading. At set it to 5.

[yw05]

yes, this only happens when i drive trains, but this did not happen before.
i am playing in singleplayer. i don't know how to apply pqtches and such to mods in mt, but i will give it a try.

EDIT
i have tried the patch, i manually added the new code. did not solve anything.

Admittedly I did not expect to see this much lag in singleplayer.

Anyway, that patch mainly addresses a networking-related issue (specifically, by not sending duplicate HUDs to the player), so I don't think it would really help much in singleplayer.

some "news" for those who actually wants to help:
after leavong the train, the game progress will be unsaved. the problem seems to be caused by advtrains. wherever the train goes in an infinitely reversing accelerating state-happens when stopping in this laggy state-the maps loads new chunks.

In terms of lag, rubberbanding is a known issue for Advtrains, and I don't think there is much we can do at the moment besides reducing the causes/sources of lag.

You can use /at_disable_step yes to disable Advtrains steps. That would (hopefully) help narrow things down. (Note that train steps are re-enabled when you restart the game, and you can use /at_disable_step no to re-enable it manually)

That said, I don't think anything significant has changed in Advtrains that would cause a performance regression.

The issue with the game progress not being saved is weird though, and I don't think Advtrains does anything to prevent game saving.

(I was going to suggest I/O bottlenecks being the culprit, but the NDB is only 245KB large and other Advtrains savefiles are too small to worth mentioning ... let's just say I got a savefile dump from a server admin some years ago and it's much larger than 245KB.)

also thanks for replying lime a human, unlike ↓

While I do have mixed feelings toward what Desour wrote (that said, not everyone has sufficient knowledge of Advtrains to be able to recognize the issues demonstrated in the video without explanation), it is worth noting that his recent work on adding support for the Tracy profiler may be helpful for identifying performance issues in the Minetest engine and hopefully also Advtrains.

[Desour]

I'm not sure if people took my request for drama too serious (the "Need more escalation!"), or if they are actually this angry on me now. But I'd like to assure you it was meant sarcastic.
And I guess my first comment can be read more aggressive than I intended it to be. So I'd like to say sorry if I've hurt you.

Anyway, back to topic.
If you're on singleplayer (which was unclear), that's quite a high amount of server lag (which causes the rubberbanding).
Still needs more information, so people can help. I.e. if this "recently" started happening, since when (since minetest upgrade, or mod upgrade, or new mod, or since you built something specific in the map)? Also, what mods do you have installed, what game, ....

FWIW, on PC there's an advanced parameter for which the default value is detrimental for my old machine; "mapblock mesh generation delay" (just search "mesh" with "advanced settings" ticked). It causes an FPS drop when you keep moving, and also affects mapblock loading. At set it to 5.

Probably won't help. Delaying mapblock mesh generation is good if you have mapblocks that change too often, so your cpu won't regenerate meshes as often. But I'm pretty sure this won't influence server lag.

[yw05]

Anyway, back to topic.
If you're on singleplayer (which was unclear), that's quite a high amount of server lag (which causes the rubberbanding).
Still needs more information, so people can help. I.e. if this "recently" started happening, since when (since minetest upgrade, or mod upgrade, or new mod, or since you built something specific in the map)? Also, what mods do you have installed, what game, ....

I think I will at least try to explain the Advtrains part of the video now that I watched it a bit more carefully.

• The rubberbanding effect was tolerable for the most part, but there were certain parts (e.g. around 1:04) where it became noticable. That said, from my experience, rubberbanding appears to be particularly visible when braking trains, and I would suspect that (aside from the usual lag arguments) the high deceleration constant (-3.3 m/s^2) also has a role here.
• The train HUD is severely out of sync. The large, two-digit display at the right end of the HUD is the speed indicator, and between 0:15 and 0:42 it showed 00 even when the train was clearly moving. My suspecion here was that Advtrains updated the driver HUD every step (*), which I fixed with a patch, but Unacceptium_core claimed that the patch did not really help, so I am out of ideas here.
• Notice that Unacceptium_core was somehow detached from the wagon entity at 1:17 despite not doing anything. It is a bit hard to make sense of what happened next, but it seems like Unacceptium_core was only briefly considered as not being on the train, after which the controls started to be registered as train controls again. However, I don't think the movement controls are sufficient to bring the train to a complete stop as shown later in the video (moving backward only brakes the train slowly; the regular brake involves near-continuous jumping which Unacceptium_core clearly did not do), and there was (apparently) also no obstacle to stop the train; the train HUD (which was delayed) was covered by the help form when it showed the train braking (3:08-3:29), so it is hard to get any clue based on that.
• The rest of the video doesn't appear to show anything new besides the server lag that Desour mentioned.

Unacceptium_core: The developer options in Android has an option to show taps (i.e. where you tapped the screen) on the screen. That would be more helpful in inferring what you did.

(*) Interestingly, the passenger HUD, which only displays short text, already has the check that prevent the same content from being sent over to clients. It seems like I forgot to port this check to the graphical train HUD when I added it in 2021, and nobody noticed this in the next ~3 years ...

[Unacceptium_core]

I'm not sure if people took my request for drama too serious (the "Need more escalation!"), or if they are actually this angry on me now. But I'd like to assure you it was meant sarcastic.
And I guess my first comment can be read more aggressive than I intended it to be. So I'd like to say sorry if I've hurt you.

Anyway, back to topic.
If you're on singleplayer (which was unclear), that's quite a high amount of server lag (which causes the rubberbanding).
Still needs more information, so people can help. I.e. if this "recently" started happening, since when (since minetest upgrade, or mod upgrade, or new mod, or since you built something specific in the map)? Also, what mods do you have installed, what game, ....

FWIW, on PC there's an advanced parameter for which the default value is detrimental for my old machine; "mapblock mesh generation delay" (just search "mesh" with "advanced settings" ticked). It causes an FPS drop when you keep moving, and also affects mapblock loading. At set it to 5.

Probably won't help. Delaying mapblock mesh generation is good if you have mapblocks that change too often, so your cpu won't regenerate meshes as often. But I'm pretty sure this won't influence server lag.

this is in singleplayer, and happened after advtrains update. not sure if advtrains is actually the problem source, bc i did place a lot of slope blocks around so maybe rendering them is difficult for my device, but i suspect advtrains still.
no, you did not hurt me, i'm broken enough to dont get hurt from this kind of text.
i wrote that the map is in my signature, and not advertising but you can just download it to see, but i can show a full mod list if needed.
that mesh setting doent't seem to help too.
when i stopped the train fast, i did hold down jump and backward (s) same time, and leaving the train without the menu i done with aux+sneak.

what i did lately is updated every mod i have, and started to experience this kind of lag. but downgrading all of my mods did not solve it, so i guess that, probably advtrains, made these .ls files OR modified a setting which is now too much for my device. because even if theres a lot of slope blocks, which render at all sides for some reason, i can freely build and do what i want. this lag did show around a year ago when i accidentally recorded* a bit of it. i would think that this is similar lag but now its continous?

*yes i know its horrible but thats all i can

[yw05]

this is in singleplayer, and happened after advtrains update.

Which version of Advtrains did you previously use? I don't think the recent changes (at least the ones this year) should cause any performance regression.

when i stopped the train fast, i did hold down jump and backward (s) same time, and leaving the train without the menu i done with aux+sneak.

That would explain things a bit. That said,

• Like I wrote earlier, it makes sense to use the "show taps" option to include the taps in the recording. That would involve much less guesswork.
• Considering that the sneak+back control activiates the emergency brake which decelerates the train at -10m/s^2 (yes, 1g deceleration ...), that rubberbanding would then not be too surprising.

what i did lately is updated every mod i have, and started to experience this kind of lag. but downgrading all of my mods did not solve it, so i guess that, probably advtrains, made these .ls files OR modified a setting which is now too much for my device

The .ls files are Advtrains savefiles, and these have been used since the 2.2.0 released back in 2021 with hardly any changes since then. While serialize_lib is not particularly performant, my experience with it is mostly tolerable, and it does should behave too badly for the savefiles in the map you linked (which add up to only around 250KB) unless your hardware has bad I/O performance, which affects MT in general and not just Advtrains.

Advtrains would benefit form a database API. The current serialization system was large written because minetest.serialize reached its limits, and using an external database API via the insecure environment was rejected partly to not complicate theinstallation process for users. However, this would mainly be relevant for servers with ~10MB savefiles and IMO less for Unacceptium_core here.

---

I added Tracy symbols to Advtrains. So far the profiling results on my side suggest that LZB and the path systems take up a lot of time (which is nothing new, to be honest; the question has been how to improve the time on this and we mainly got another tool now to compare the differences).

Unacceptium_core: now that you have narrowed down the issue to Advtrains, can you compare the lag between the following situations?

• Not having moving trains (or: enable /at_disable_step yes)
• Letting trains run on their own, but do not ride the trains.
• Traveling in the train as a regular passenger (i.e. not on the driver stand).
• Driving the train.

[Blockhead]

Big thanks to ywang for trying to narrow down problems for Unacceptium in this thread so far. Now I have another suggestion. In recent versions of Metrotest, the Woolen Mesh (wesh) speed signs were added. While these look nice, they also add heaps of polygons. Also, sending mesh polygons to the GPU seems to take a lot of CPU power in Minetest, power that would otherwise be going towards simulating Advtrains.

Does the game perform worse when there are too many wesh nodes? Have you considered using the Ks signs? (You could modify the textures and add more speeds as well).

[Unacceptium_core]

Big thanks to ywang for trying to narrow down problems for Unacceptium in this thread so far. Now I have another suggestion. In recent versions of Metrotest, the Woolen Mesh (wesh) speed signs were added. While these look nice, they also add heaps of polygons. Also, sending mesh polygons to the GPU seems to take a lot of CPU power in Minetest, power that would otherwise be going towards simulating Advtrains.

Does the game perform worse when there are too many wesh nodes? Have you considered using the Ks signs? (You could modify the textures and add more speeds as well).

it did became after i added the wesh models, the only reason i did not expect it to be the problem is theres some areas which has much more than one or two per chunk, and it did not made me lag, but i will look into it*.
i will also look after those ks signs.

yw05 i will try these in this weekend, im tired now. i will post a reply when i find anything, i will try to make a screen record too.
also thanks for all of your time and suggestions.

* mean the wien style stations, those have a lot of wesh arcs.

[Nininik]

I have a similar issue even tho I mostly have a testing world for my server, somehow it still lags even tho there is like very few meshes , and loading up new terrain lags a lot idk why and I randomly get lag spikes

[Blockhead]

and loading up new terrain lags a lot idk why and I randomly get lag spikes

The game has to actually generate the new terrain, so that part makes complete sense. If the game struggles to run well in existing terrain, I would expect generating new terrain to make it really struggle. The new terrain also gets saved to storage, and a lot of lower-end phones and laptops have slow eMMC storage, which makes the whole thing slower.

[MrPhil]

Disregard everything I said - somehow I didn't realize this was on Android...

Hitting F5 once to put the client in partial debug mode for the video would be helpful in differentiating video performance issues from other game lag.

How much difference this would make would depend upon how you're running the game and if this problem is primarily video-performance-related but Lua-intensive mods like advtrains, technic, digilines etc., benefit greatly from LuaJIT. If you're compiling the client/server yourself then pulling and compiling/installing the latest LuaJIT and then making sure that MT is using it could be helpful if you're on the edge, performance-wise.

I've always done this with servers I run but recently started doing this when I compile a new desktop client as well, although I haven't profiled it and don't really know how much it helps. I believe that a fair amount of Lua code runs client-side but I don't know for sure if that's the case when you're just connecting to an external server. Perhaps someone who actually knows could weigh-in on this.

- Phil

[Unacceptium_core]

i found out that destroying an unknown node results in instant response as an error in chat, and chunk loading is also almost unnoticeably fast. before i played with 10 wagon long trains with instant responsive minetest
but now i cannot believe that what they say is no modifications happened in these mods but i cannot even drive a single traincar anymore. i had given up hope on this. thats why i did not respond. i had tried so much settings and had to remake the .conf file a lot but nothing helped. i cannot believe that some small modifications can bring minetest on its knees. i play much heavier games and i have almost never experienced such a performance lost, even with overmodding other heavy games, minetest performance is just funny. idk if i even want to keep trying fixing this anymore like i spent so much of my free time and energy into trying to solve this and its still there.