101 Profiling

Agenda

1. Java Context
2. Java profilers
3. Introduction to VisualVM
4. Profilers in Action
5. Summary
6. References
7. Homework
8. Q&A

Educational Goals

1. Learn to use a Java Profiler
2. Learn to use JVM flags

Java Context

1. Java Lifecycle
2. Java Architecture
3. Java Memory Model
4. Java & Containers
5. JVM Flags

Java Lifecycle

Java Architecture

Java Memory Model

Java & Containers

JVM Flags

java -Xms256m -Xmx256m \
    -verbose:gc  \
    -XX:+UseG1GC -XX:-DisableExplicitGC \
    -Djava.security.egd=file:/dev/./urandom \
    -Dsun.management.jmxremote.level=FINEST \
    -Dsun.management.jmxremote.handlers=java.util.logging.ConsoleHandler \
    -Djava.util.logging.ConsoleHandler.level=FINEST \
    -Dcom.sun.management.jmxremote.local.only=false \
    -Dcom.sun.management.jmxremote=true \
    -Dcom.sun.management.jmxremote.ssl=false \
    -Dcom.sun.management.jmxremote.authenticate=false \
    -Dcom.sun.management.jmxremote.port=9010 \
    -Dcom.sun.management.jmxremote.rmi.port=9010 \
    -Dcom.sun.management.jmxremote.host=0.0.0.0 \
    -Djava.rmi.server.hostname=0.0.0.0 \
    -agentlib:jdwp=transport=dt_socket,server=y,suspend=n,address=5005 \
    -server \
    -jar -jar app.jar
                  

More flags...

Java profilers

1. What is Profiling?
2. What kind of problems try to solve?
3. Alternatives

What is Profiling?

The term profiling describes a dynamic analysis that covers issues of the resource management of a program during execution.

Performance analysts profile their programs to find methods that are worth optimizing: the “hot” methods.

What kind of problems try to solve a Profiler?

1. CPU Bottleneck
2. Memory Leak
3. Multithreading problems
4. Define JVM Settings

Alternatives

1. JProfiler (Commercial Product)
2. YourKit (Commercial Product)
3. Java VisualVM

References

Articles

1. A Guide to Java Profilers
2. Memory Profiling using Visual VM
3. The art of profiling
4. Java is a first class citizen in a Docker ecosystem
5. Java 9 by Example

Books

Books

Books