AdoptOpenJDK/jitwatch

Log analyser / visualiser for Java HotSpot JIT compiler. Inspect inlining decisions, hot methods, bytecode, and assembly. View results in the JavaFX user interface.

Source code at GitHub https://github.com/AdoptOpenJDK/jitwatch

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  "description": "Log analyser / visualiser for Java HotSpot JIT compiler. Inspect inlining decisions, hot methods, bytecode, and assembly. View results in the JavaFX user interface.",
  "fullName": "AdoptOpenJDK/jitwatch",
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  "language": "Java",
  "name": "jitwatch",
  "pushedAt": "2025-11-11T20:31:12Z",
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  "topics": [
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  "url": "https://github.com/AdoptOpenJDK/jitwatch"
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JITWatch

Log analyser and visualiser for the HotSpot JIT compiler.

Video introduction to JITWatch video
Slides from my LJC lightning talk on JITWatch slides

For instructions and screenshots see the wiki

https://github.com/AdoptOpenJDK/jitwatch/wiki

The JITWatch user interface is built using JavaFX which is downloaded as a maven dependency for JDK11+.

For pre-JDK11 you will need to use a Java runtime that includes JavaFX.

maven

mvn clean package && java -jar ui/target/jitwatch-ui-shaded.jar

Build an example HotSpot log

# Build the code and then run
cd scripts && ./makeDemoLogFile.sh