Unsafe World Random Access Detector Mod FAQ
10 questions players actually ask, answered.
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.
How do I reproduce the crash so the detector can catch it?
Run the same world, modpack, and actions that triggered the crash before, ideally with the same chunk loading or worldgen activity happening. The detector only reports what actually occurs, so you need the unsafe access to happen again while it's watching.
Can I use this alongside performance mods like Sodium, Lithium, or C2ME?
Yes, it's designed to coexist with other mods and won't crash when used together. If you already run C2ME, though, the detector is unnecessary since C2ME handles concurrent world access itself.
Will this mod hurt my performance or FPS?
It's a diagnostic tool, so its overhead is minimal and mainly applies when it's actively checking world access. You shouldn't notice a meaningful FPS impact during normal play.
The stack trace points to a mod I don't recognize. How do I figure out which mod it is?
Look at the package and class names in the stack trace and match them against the mod list in your launcher or mods folder. The topmost mod-specific frame is usually the culprit, even if the trace passes through vanilla or library code first.
Can I leave this mod installed permanently, or should I remove it after finding the cause?
You can leave it installed, but it's meant as a temporary diagnostic tool. Once you've identified and fixed the offending mod, removing it keeps your setup clean, unless you want to keep monitoring for future issues.
The detector reports an unsafe access but the game doesn't crash. Should I care?
Yes, an unsafe access is still a latent bug even if it didn't crash this time, since it can cause crashes or corrupted world state under different timing. Treat any warning as a sign to investigate the reported mod.