Paper-238 Chunk Unloading Issues (Performance/Server Deadlocks)

[Stixil]

Timings or Profile link:

https://timings.aikar.co/?id=99b0d1a6f5834024b43470ce38f714a5 https://spark.lucko.me/#93ZuNfru67

Description of issue:

Chunks appear to not unload properly causing memory buildup and leads to poor performance and server crashes when maximum memory is reached (deadlock hang).

Plugin list:

[19:43:55 INFO]: Plugins (41): AcoWorth*, AngelChest, BlockLocker, BossShopPro, BungeeTabListPlus, CoreProtect, EntityTrackerFixer, ExploitFixer, FarmLimiter, HamsterAPI*, Harbor, IllegalStack, InventoryRollback, JukeBox, LuckPerms, Multiverse-Core, MyCommand, NoMobGriefing, NoteBlockAPI, PL-Hide-Pro, PlaceholderAPI, ProtocolLib, PvPToggle, QuickShop, spark, Spartan, StaffFacilities, StayPut, StickyChatBukkit, StickyCommands, StickyWallet, Tamer, Vault, ViaBackwards, ViaRewind, ViaVersion, ViaVersionStatus, WarpSystem, WorldEdit, WorldGuard, WorldGuardExtraFlags

I have tested it a small amount on a fresh server and have still had the issue of chunks not unloading. Timings taken from production server with a normal player load, more chunks end up loading that way.

Config files:

bukkit.yml - https://pastebin.com/yejHML5N spigot.yml - https://pastebin.com/zVQMGGPx paper.yml - https://pastebin.com/zNLNMTb8 server.properties - https://pastebin.com/8EdVng5W

Other helpful links

It seems to be a similar issue to this issue in Paper-202 but still is present in 238. https://github.com/PaperMC/Paper/issues/4352

Paper version:

[19:47:34 INFO]: This server is running Paper version git-Paper-238 (MC: 1.16.3) (Implementing API version 1.16.3-R0.1-SNAPSHOT) [19:47:34 INFO]: Checking version, please wait... [19:47:34 INFO]: Previous version: git-Paper-236 (MC: 1.16.3) [19:47:34 INFO]: You are running the latest version

[Proximyst]

Has this been replicated without plugins? It might simply be a plugin adding a ticket for every loaded chunk (🤦🏻‍♀️).

[Stixil]

Hi, thanks for the response. We have had the same issue on our testing server with only one plugin installed that was not on our original list (we used this just to expedite having more chunks loaded, and made sure it was not installed on the server with the original report issue to rule out those plugins.)

https://www.spigotmc.org/resources/betterrtp-random-wild-teleport.36081/

I can get another replication (with no plugins, or just the one RTP plugin) with timings links this time if it would help. Thanks!

[Proximyst]

This has been reported by @clrxbl to also occur. I'll mark this issue as accepted.

[Stixil]

Fantastic, thanks for the help. I went ahead and just finished recreating the issue with zero plugins, here is a timings report from just before the crash when memory was almost maxed out, hope it helps. Let me know if you need any more info.

https://timings.aikar.co/?id=d47588295e2743aebefe096a736ebfd8

[16:11:18 INFO]: This server is running Paper version git-Paper-252 (MC: 1.16.3) (Implementing API version 1.16.3-R0.1-SNAPSHOT) [16:11:18 INFO]: Checking version, please wait... [16:11:19 INFO]: You are 1 version(s) behind

[16:11:32 INFO]: Plugins (0):

[tomasdev]

Is it possible this is still an issue on 1.17.1?

[Owen1212055]

Is this an issue you can still experience as of 1.19? Additionally, are you able to see if this issue is still around with the chunk recode PR?

[Owen1212055]

Because of the large changes with the chunk system, this will be closed as this may not be an issue anymore. However, if you still are experiencing this issue please comment and this issue will be reopened.

Thank you! 😄