High ms ticks in 1.14+, player cannot interact with world normally

We are now closing this issue, because it has grown too indistinct. Note that this does not mean that we think performance is perfect - we will keep working on performance optimizations for future versions.

However, this Jira issue in specific has outgrown its usefulness, containing a range of different concerns all mixed together. If you still experience performance problems, please identify what the scenario is and submit specific bugs, so separate issues can be tracked separately. Also please make sure to include debug reports and all relevant information when reporting such bugs.

Note: Jira is not a discussion forum. If you have performance issues, follow the instructions above rather than posting further comments on this issue.

This bug can have multiple symptoms, including, but not limited to:

• Blocks reappear after being mined
• Entities don't move
• Chunks don't load and when entering them, the player falls out of the world
• Cannot open chests and other containers
• Cannot interact with entities

Also, when this issue occurs, the a line like this:

Can't keep up! Is the server overloaded? Running 5000ms or 100 ticks behind

will be printed occasionally in the game console.

Sometimes this issue will become so bad that it will crash the server. In that case the crash report usually has a line like Description: Watching Server.

If you experience this issue, please run a complete debug dump by following these steps:

1. Generate a debug profiling (.txt file):
   • Press F3 + L

Those files will be generated in the debug folder of your Minecraft instance. If you are on singleplayer, access your game directory. If you are on server, report to your system administrator. If you don't have op permission, either ask your server admin to perform the dump, or if you are on singleplayer, open your world to LAN with cheats on.