Unsafe World Random Access Detector Mod Wiki
Unsafe World Random Access Detector Mod Wiki & Guide
wiki.9minecraft.net/unsafe-world-random-access-detector-mod/
Unsafe World Random Access Detector Mod is a mod that detects unsafe off-thread world random access, helping to find causes of “Accessing LegacyRandomSource from multiple threads” crash. This is useful for finding the cause of mysterious crashes with Accessing LegacyRandomSource from multiple thread
Guides
Step-by-step, in-game.
How to Read the Crash Report and Find the Culprit ModUnderstanding what the mod prints When the Unsafe World Random Access Detector catches an off-thread world random…How to Tell Whether You Actually Need This ModWhen the detector helps This mod is a diagnostic tool, not a fix. It is worth keeping installed when you are chasing…How to Trigger the Detector Reliably for TestingWhy you need a repeatable trigger A stack trace is only useful if you can reproduce it. The detector fires whenever…How to Use the Detector Alongside Other Performance ModsCompatibility basics The detector is designed to coexist with other mods, including concurrent chunk management mods.…
Frequently asked questions
How do I know the detector is actually running?
Check your game log on startup for the mod's initialization message, and watch for its warnings to appear in the log or console when an unsafe access happens. If you never see any output even after a crash, the detector likely isn't loaded or is being suppressed by another mod.
What does the detector actually output when it catches something?
It prints a warning to the log identifying the offending thread and a stack trace pointing to the code that accessed the world's random source off-thread. That stack trace is what you use to trace the access back to a specific mod.
Does this mod fix the 'Accessing LegacyRandomSource from multiple threads' crash?
No, it only detects and reports the unsafe access so you can find the cause. You still need to remove, update, or reconfigure the mod responsible for the crash.
I installed it but the crash still happens and I see nothing useful. What am I doing wrong?
Make sure you're reading the full latest log rather than just the crash report, since the detector's warning may appear earlier in the log than the crash itself. Also confirm the detector loaded before the crash occurred, because a crash during early startup can happen before it initializes.