Command
/jfr
Starts or stops a Java Flight Recorder performance recording of the game.
Syntax
| /jfr (start|stop) |
Details
| Permission level | 4: server owners and the server console |
| Works in | The server console, the owner of a singleplayer world with cheats enabled, and operators with level 4 on multiplayer servers. Command blocks and functions cannot run it, because they only have level 2. The command exists only if the Java version running the game supports Java Flight Recorder. |
| Result | start reports "JFR profiling started". stop reports "JFR profiling stopped and dumped to" with the path of the saved recording, which can be clicked to copy it. The number /execute store saves is 1. |
| start | Begins a recording. Fails with "Failed to start JFR profiling" if the recording cannot be started. |
| stop | Ends the recording and saves it to a file. Fails with "Failed to dump JFR recording" if no recording could be saved. |
Examples
/jfr startStarts a performance recording.
/jfr stopStops the recording and shows where the file was saved.