
FullStack Watchdog
Make Watchdog crashes show all the code that was running for all threads
Screenshots

About this Mod
This is a tiny server-sided mod that makes it so that the logs show more information when the Watchdog system on the server has killed the server due to being deadlocked or stuck so long. The crash report log will now show all of the code that was running at the time of the deadlocked server. In other words, the full stacktrace of all threads instead of the normally truncated (shortened) version.
In theory, this should help with diagnosing what modded code or mixin has caused an "off-thread" to lock up. When a thread locks up, the server thread gets stuck and if it remains stuck for so long, the Watchdog kills it because a tick took too long to complete. It won't help solve all deadlock issues. But it might get you just enough info to track down the cause of a few deadlocks.
Image below is an example of before and after this mod is put on (Gallery tab shows image better): 
Yes you may ship this mod in a modpack. The client can also have this mod on but it won't do anything on client since the Watchdog system is only ran on servers. You can also run servers with this mod only on the server. Clients without this mod can still connect.
NOTE 1: NeoForge 20.4.107 and newer already has this mod merged into it! You do not need this mod in NeoForge for 1.20.4 MC or newer! https://github.com/neoforged/NeoForge/pull/512
NOTE 2: Fabric API 0.104.0+1.21.2 and newer already has this mod merged into it! You do not need this mod in Fabric for 1.21.2 MC or newer! https://github.com/FabricMC/fabric/pull/4052
Available Versions
How to Install FullStack Watchdog on Your Server
Order Server
Order a Minecraft Java server with at least 3 GB RAM (4 GB recommended).
Set fabric Loader
In the panel under "Egg", select the fabric loader and matching Minecraft version (1.21.1).
Install Mod
Open the mod browser in the dashboard and search for "FullStack Watchdog". Click "Install" – done! Alternatively, upload the .jar via SFTP to the /mods folder.
Compatibility
Mod Loaders
Minecraft Versions
1.21.1, 1.21, 1.20.6 (+16 more)
Server-side
✓ RequiredRecommended RAM
4 GB(min. 3 GB)Frequently Asked Questions
FullStack Watchdog server crashes on startup – what to do?
Most common cause: wrong fabric version or insufficient RAM. Check the server log (latest.log) for "OutOfMemoryError" or "Mixin" errors. With Mado Hosting: ensure at least 3 GB RAM is allocated and the loader matches the mod version (1.21.1). You can switch loaders with one click in the panel.
Is FullStack Watchdog compatible with fabric and forge and neoforge?
FullStack Watchdog officially supports fabric, forge, neoforge for Minecraft 1.21.1, 1.21, 1.20.6. Note: Forge and Fabric mods are NOT cross-compatible – pick one loader and stick with it. The Mado dashboard automatically detects incompatible loader combinations.
Server lagging with FullStack Watchdog – how to optimize performance?
Recommended RAM: 4 GB (per 8 players). Use /spark profiler to check if FullStack Watchdog consumes the most tick time. Common fixes: reduce server view-distance to 8-10, install "performant" or "starlight" as supplementary mods on Forge. With Mado Hosting, your server runs on NVMe SSDs with dedicated CPU cores for minimal latency.
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Rent Modded Server
Install FullStack Watchdog with just one click on your server.