Commands/debug

This article is about command that runs time profiler and function trace. For performance profiler, see Commands/perf. For jvm profiler, see Commands/jfr. For other uses of "debug", see Debug.

debug

Permission level required	3
Restrictions	None

Starts or stops a time profiller session.

Syntax

debug start

Starts a new debug time profiler session.

debug stop

Stops the active debug time profiler session.

debug function <name>

Used the same way as /function to get more detailed information of commands' execution.

Arguments

<name>: function

It must be a resource location, which refers to a single function, or one prefixed with a #, which refers to a function tag.

Result

Command	Trigger	Java Edition
/debug start	a debug profiling session has already been started	Failed
/debug stop	there's no debug profiling session running.
/debug function	the specified functions or function tags do not exist
any	On success	Starts/stops the debug profiling, or get more detailed information of function execution.

Output

Command	Edition	Situation	Success Count	/execute store success ...	/execute store result ...
any	Java Edition	On fail	N/A	0	0
/debug start		On success	N/A	1	0
/debug stop		On success	N/A	1	the average tps (ticks per second) during debug profiling
/debug function		On success	N/A	1	the number of commands executed (whether successfully or not) plus the number of embedded functions. See also Commands/function

File structure

Function trace

When using /debug function, a txt file titled debug-trace-yyyy-MM-dd_HH.mm.ss.txt is created in .minecraft/debug.

In this file,

• [C] <command> means the <command> is executed.
• [M] <message> means a message is returned.
• [E] <message> means a failure message is returned.
• [R = <num>] <command> means the <command> returns a brigadier return value.
• [C] <command> -> <num> means the <command> is executed and returns a brigadier return value.
• [F] <function> size=<num> means a function is called.

For most of commands, the brigadier return value is equal to the result value that can be stored with /execute store result.

But for /execute ... with one or more of the following subcommands, the brigadier return value is the number of times that the last subcommand is executed successfully:

• ... if ... (not at the end)
• ... unlesss ... (not at the end)
• ... as <targets> ...
• ... at <targets> ...
• ... positioned as <targets> ...
• ... totated as <targets> ...
• ... facing entity <targets> <anchor> ...

Profile result

When using /debug stop, a txt file titled profile-results-yyyy-MM-dd_HH.mm.ss.txt is created in .minecraft/debug, which includes the result of profile dump.

Report

When using /debug report, a ZIP file is created with in .minecraft/debug/profiling the following structure:

• debug-report-yyyy-MM-dd_HH.mm.ss.zip
  • levels
    • minecraft or <other custom namespaces>
      • overworld or the_end or the_nether or <other custom dimensions>
        • block_entities.csv: Contains a list of block entities in the world in the format x,y,z,type.
        • chunks.csv: Contains a list of chunk information in the format x,z,level,in_memory,status,full_status,accessible_ready,ticking_ready,entity_ticking_ready,ticket,spawning,entity_count,block_entity_count.
        • entities.csv: Contains a list of entities in the world in the format x,y,z,uuid,type,alive,custom_name.
        • example_crash.txt: An example crash file.
        • stats.txt: Contains some stats.
  • classpath.txt: Contains the file paths of the external jars Minecraft uses.
  • example_crash.txt: An example crash file.
  • gamerules.txt: A plain text file containing a list of game rules and their values (<gamerule>=<value>).
  • stats.txt: Contains some stats.
  • threads.txt: All running threads.

History

Java Edition
1.3.1		12w27a			Added /debug.
1.8		14w31a			/debug can now be run in single-player.
					Added /debug chunk.
1.8.1		pre1			Removed /debug chunk.
1.13		18w03a			Added commands to the profiler.
1.14.4		pre1			Added /debug report, used to get more detailed information while debugging performance.
1.17		21w15a			Added /debug function
		Pre-release 1			Removed /debug report. Replaced by F3+L and /perf.

Commands

View at: Template:Commands/content [edit]