arthas-trace

Trace Java method execution paths and timing.

TLDR

Trace method execution

$ trace [com.example.MyClass] [myMethod]

Trace with condition

$ trace [com.example.MyClass] [myMethod] '#cost > 100'

Trace all methods in class

$ trace [com.example.MyClass] *

Trace with invocation count

$ trace -n [5] [com.example.MyClass] [myMethod]

SYNOPSIS

trace [-n count] [--skipJDKMethod] class-pattern method-pattern [condition-express]

trace is an Arthas command that traces method execution paths and timing. It shows the call hierarchy within a method invocation, highlighting which sub-methods consume the most time.
This is invaluable for identifying performance bottlenecks without adding logging or profiling instrumentation.

PARAMETERS

class-pattern

Class name (supports wildcards)

method-pattern

Method name (supports wildcards)

-n count

Stop after count invocations

--skipJDKMethod

Skip tracing JDK methods

condition-express

OGNL condition (e.g., '#cost > 100')

OUTPUT

Shows call tree with:
- Method names
- Execution time
- Nested call structure

CAVEATS

Deep traces may produce verbose output. Performance overhead increases with trace depth. Use conditions to limit output.

HISTORY

trace is a core diagnostic command in Arthas, essential for performance troubleshooting in production Java applications.