Roastd Built by Hostd The verdict is in. 2 crit1 warn Roast your own server

Ticks are taking 1101.6ms against a 50ms budget.

2 critical, 1 warning found. Every finding below comes from what was actually in the pasted files. Treat the fixes as suggestions: they cover the common causes, and this case may need more digging.

Paper1101.6ms per tick (budget 50ms)0.91 TPS30386 entities

Log from mclo.gs/qSN0YN2Profile from spark.lucko.me/TNkxcteaYs

This looks like a client log, not a server log. The findings below apply to the player's machine.

critical

Ticks are taking 1101.6ms against a 50ms budget.

The server thread is averaging 1101.6ms per tick against a budget of 50ms. The worst tick in that window was 1282.2ms. A tick that runs past the budget is time the server cannot give back, and it shows up to players as rubber-banding and slow block breaking. The heaviest chunk in this profile holds 8706 entities, which is the first thing to look at.

critical

8706 entities are sitting in one chunk at -68, 2.

world chunk -68, 2 (around x -1088, z 32) holds 8706 entities: 5655 slime, 3051 item. Every one of them is ticked, so a single chunk like this can hold the whole server back, and it is 29% of the 30386 entities in the profile. Go to those coordinates and look for a mob farm without a killing layer, an item backlog on the floor, or a bred animal pen nobody culls. The next worst are world chunk -69, 2 (around x -1104, z 32) and world chunk -68, 3 (around x -1088, z 48).

warning

An unrecognised crash: NoClassDefFoundError in Initializing game

The crash report says it died in Initializing game on the Render thread. The exception is java.lang.NoClassDefFoundError: org/lwjgl/vulkan/VkPhysicalDeviceProperties2. Every frame in the stack is vanilla or loader code, so the report itself names no mod. No frame in the stack carries a mod annotation, so there is nothing to bisect from here: halve the pack instead, and bring the share link to our Discord.

The log

As received, after redaction.

  1. [21:43:48] [main] [com.mojang.blaze3d.platform.NativeLibrariesBootstrap/WARN]: Failed to load Vulkan loader
  2. java.lang.NoClassDefFoundError: org/lwjgl/vulkan/VK
  3. at com.mojang.blaze3d.platform.NativeLibrariesBootstrap.tryLoadingVulkan(NativeLibrariesBootstrap.java:310)
  4. at com.mojang.blaze3d.platform.NativeLibrariesBootstrap.loadLibraries(NativeLibrariesBootstrap.java:85)
  5. at net.minecraft.client.main.Main.main(Main.java:142)
  6. at java.base/jdk.internal.reflect.DirectMethodHandleAccessor.invoke(Unknown Source)
  7. at java.base/java.lang.reflect.Method.invoke(Unknown Source)
  8. at com.modrinth.theseus.MinecraftLaunch.relaunch(MinecraftLaunch.java:61)
  9. at com.modrinth.theseus.MinecraftLaunch.main(MinecraftLaunch.java:28)
  10. Caused by: java.lang.ClassNotFoundException: org.lwjgl.vulkan.VK
  11. at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(Unknown Source)
  12. at java.base/java.lang.ClassLoader.loadClass(Unknown Source)
  13. ... 7 more
  14. [21:43:51] [Datafixer Bootstrap #0] [com.mojang.datafixers.DataFixerBuilder/INFO]: 295 Datafixer optimizations took 1144 milliseconds
  15. [21:44:01] [Render thread] [com.mojang.authlib.yggdrasil.YggdrasilAuthenticationService/INFO]: Environment: Environment[sessionHost=https://sessionserver.mojang.com, servicesHost=https://api.minecraftservices.com, profilesHost=https://api.mojang.com, name=PROD]
  16. [21:44:02] [Render thread] [net.minecraft.client.Minecraft/INFO]: Setting user: {MINECRAFT_USERNAME}
  17. [21:44:02] [Render thread] [net.minecraft.client.Minecraft/INFO]: Backend library: LWJGL version 3.4.1+2
  18. [21:44:02] [Render thread] [net.minecraft.client.Minecraft/WARN]: Detected unexpected shutdown during last game startup: resetting fullscreen mode
  19. [21:44:02] [Render thread] [net.minecraft.client.Minecraft/WARN]: Detected unexpected shutdown during last game startup: forcing preferred graphics API to OpenGL
  20. ---- Minecraft Crash Report ----
  21. // You should try our sister game, Minceraft!
  22. Time: 2026-08-06 21:44:02
  23. Description: Initializing game
  24. java.lang.NoClassDefFoundError: org/lwjgl/vulkan/VkPhysicalDeviceProperties2
  25. at com.mojang.blaze3d.vulkan.VulkanBackend.
  26. (VulkanBackend.java:73)
  27. at net.minecraft.client.PreferredGraphicsApi.getBackendsToTry(PreferredGraphicsApi.java:37)
  28. at net.minecraft.client.Minecraft.
  29. (Minecraft.java:508)
  30. at net.minecraft.client.main.Main.main(Main.java:278)
  31. at java.base/jdk.internal.reflect.DirectMethodHandleAccessor.invoke(Unknown Source)
  32. at java.base/java.lang.reflect.Method.invoke(Unknown Source)
  33. at com.modrinth.theseus.MinecraftLaunch.relaunch(MinecraftLaunch.java:61)
  34. at com.modrinth.theseus.MinecraftLaunch.main(MinecraftLaunch.java:28)
  35. Caused by: java.lang.ClassNotFoundException: org.lwjgl.vulkan.VkPhysicalDeviceProperties2
  36. at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(Unknown Source)
  37. at java.base/java.lang.ClassLoader.loadClass(Unknown Source)
  38. ... 8 more
  39. A detailed walkthrough of the error, its code path and all known details is as follows:
  40. ---------------------------------------------------------------------------------------
  41. -- Head --
  42. Thread: Render thread
  43. Stacktrace:
  44. at com.mojang.blaze3d.vulkan.VulkanBackend.
  45. (VulkanBackend.java:73)
  46. at net.minecraft.client.PreferredGraphicsApi.getBackendsToTry(PreferredGraphicsApi.java:37)
  47. at net.minecraft.client.Minecraft.
  48. Surface Info:
  49. GFLW Platform: win32
  50. Graphics Device:
  51. GL debug messages:
  52. Is Modded: Probably not. Client jar signature and brand is untouched
  53. Universe: 404
  54. Type: Client
  55. Locale: en_US
  56. System encoding: Cp1252
  57. File encoding: UTF-8
  58. CPU: 8x Intel(R) Core(TM) i5-9300H CPU @ 2.40GHz
  59. #@!@# Game crashed! Crash report saved to: #@!@# C:\Users\********\AppData\Roaming\ModrinthApp\profiles\Vanilla 26.2\crash-reports\crash-2026-08-06_21.44.02-client.txt
  60. WARNING: Unknown module: jdk.internal specified to --add-opens
  61. [MODRINTH] Unable to call JDK findMainMethod. Falling back to pre-Java 25 main method finding.

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