Inexplicable high ping on Fabric modded server
Hello, I'm here with a strange problem that I don't really know how to troubleshoot. I have a lot more experience as a spigot/paper server admin from back in the day, for a small public server. These days, I'm hosting a private fabric modded server with my own modpack for a few friends.
I run a 1.20.1 fabric modpack with a few big content mods (Create, Botania, Aquamirae, etc.) and a lot of optimization mods as well. Not sure how to dump a full list of mods but if there's a command I can use for that I would post it here.
The problem: Every so often, players will experience unusually high ping. Sometimes they experience extremely high ping on joining, other times it just happens randomly while playing normally. Sometimes it's both. I find this happens more often to players in other countries, I have a friend from Canada who experiences ping issues more often, but it happens just as much to people who live in the US, too. (Server is hosted in Texas, my host is ExtraVM). I'm already running Krypton on both the client and server side, so I'm a bit puzzled on what to do about this issue, or how to even begin to troubleshoot it. The server performance is actually stellar with all the optimization mods, It's rare to see mspt go over 20 or 30. If anyone knows how I can troubleshoot these issues with ping, I would really appreciate it! Thank you π
48 Replies
Thanks for asking your question!
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Requested by aeonlamb#0
!logs
Please check your server log for errors from your plugins.
If you need further help understanding the errors, please send us the whole log file.
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Logs are stored in
<server_directory>/logs/. Search for a file explorer in your server's management interface and navigate to that directory. Once you've opened that up, search for the latest.log file. Some providers have a separate page for logs and may hide the "logs" folder.
On Aternos:
β’ Go to https://aternos.org/log/.
On Minehut and server.pro:
β’ Go to the "files" tab in the left menu.
β’ Navigate to the root directory of your server.
β’ From there navigate to /logs/latest.log.
What should I do with the log?
β’ First of all, read it! I mean, that's what you do all the time when you run a server, isn't it? Try to locate any errors that have anything to do with the issue you are facing.
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β’ If you have trouble downloading the log file, copy/paste the text to a paste service (like mclogs). Copy the link that it gives you and send it to us. (Don't worry, McLogs hides your users' IPs.)Admincraft Canned Responses
!spark
Spark Profiler
Spark can be used to see why your server or client is lagging.
Users can share a spark report via
/spark profiler start --timeout 300 which creates a report after 5 minutes. The spark report is useful in debugging why your server is lagging, so ideally you should always provide one while asking for support.
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@vivi Show us that and we can get started.
I can't think of any relevant logs to share, and I didn't really think to start a profiler when people were experiencing the issue, but I've got this profiler report I took a few days ago, https://spark.lucko.me/1Yawq1TsJS
spark
spark is a performance profiler for Minecraft clients, servers, and proxies.
Spark Profile Analysis
β Processing Error
The bot cannot process this Spark profile. It appears that the platform is not supported for analysis. Platform: Fabric
Requested by aeonlamb
Just share your logs, you'd be surprised what info we can get from seemingly nothing.
Also what's your client modlist? I've seen C2ME cause some weirdness and Krypton is known to either help or really hurt in stuff like this.
there's ~130 mods in total, c2me is one of them
I can try removing that one from clientside
Yeah good thing to do.
C2ME tends to be a bit fucky.
Unrelated, how does krypton work? Just curious
It just makes the networking stack faster with some optimizations.
https://mclo.gs/dInd5q4
here's some logs from earlier today, people were getting a ton of lag out of nowhere. afaik server tps was fine, just people getting problems with ping. i wasn't online at the time but i was told about it and decided it was time to investigate further lol
Hmm...
Ok so it died for everyone.
Exactly what Iβm interested in, as you said it can help or hurt
Depends on your modlist. Sometimes it'll hurt, other times it's great.
Right so the server connection remained stable but laggy as fuck over 15 mins and everyone DCd.
Are you on Linux or Windows?
Maybe I should try removing kryptonβ¦
well, i think they logged out just because ping was so bad it was unplayable. one server mod i have is timeoutout, because ping problems were even worse before installing it- some people had their connections timed out and couldn't even connect, with timeoutout they're allowed to connect if they just wait long enough (this doesn't happen all the time or for everyone, but it helped some people)
Can't ever hurt to give it a test.
Linux or Windows??
linux, my host is ExtraVM, I've been using them for years
I mean your daily driver OS.
I'm thinking on network diagnosis tools.
oh client side? windows 10
Just use wsl smh
Traceroute, net-tools etc etc
I mean not everyone can do that to install mtr. :LUL:
Fuck, what's that one site? The one that diagnoses MC servers?
mcsrvstat.us?
Yes, that one.
I'm kinda wondering if it'd see the server fuck out.
This is a pretty difficult problem to troubleshoot tbh.
I submitted a ticket to extravm before asking about the ping issues and they told me they hadn't had any oddities in the network, and that it must be something misconfigured in my modpack, which I'm inclined to believe since this is my first time hosting a modded server/making a modpack
yeahhh :(
Iβm trying to reach out to my community to see if someone could get on and test krypton
i really appreciate it π«Ά
this may be a small server of just a couple friends but I'm stubborn and want to fix this problem if I can lmao
Ok hang on, are you running the server on a bare VM?
I also have this issue lmao, kinda annoying for sure
nope, pterodactyl is the panel they use i believe
Ah, unfortunate.
I was gonna suggest UnifiedMetrics and NodeExporter.
i have a VPS for personal use but i can't be bothered to host mc servers from there, i mostly use that to host a discord bot
Perhaps try a binary search with a few weird mods?
!binary
Binary search your plugins
Remove half of your non-essential (ie not things like PAPI or LuckPerm) plugins and see if the problem is fixed.
If it still persists, the cause is in the half still installed.
Continue to halve the remaining plugins until you've narrowed it down to a single plugin.
Congratulations, you found the culprit.
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Last time I did a binary search, there were two β οΈ
Had to do this twice
F
I could certainly try that but with 130 mods, a lot of them required on the client too, it'd be a real pain in the ass... I've already tried removing a few mods here or there to try to alleviate it, and it's hard to tell if anything I tried worked since the problem comes up so sporadically, I can't really pinpoint a cause or any way to reproduce it :/
Without being able to reproduct the issue it's very hard to tell what it might be. :/
there was this one client mod i found that lets you inspect packets, could this be useful? https://modrinth.com/mod/gadget
Have you tried with krypton/without?
i told people to try uninstalling krypton earlier today, i guess we'll see what the results are, everyone called it for the day after all the lag
Server side too?
i can try that
what does c2me mess with that could cause ping issues anyway?
General mod stability.
Tried with/without krypton
A few ms worth of difference for me
After waiting for it to settle*