1. Death to the Java Profiler
How to make Java really fast.

2. Intro
Start install of
What is healthy response time of Threads of load Zero think time Java → TCP → Java where both Java’s are on the same machine?

3. The Problem
healthcare.gov-ish performance
Multi-second response time

4. Methodology
….home pages of the major hotel sites from the ten largest U.S. metropolitan areas on high-speed links attached to key points on the largest U.S. Internet Service Provider (ISP) backbones.

5. The Dream
The latest version:

6. JPetStore is Old School Performance
Fast before:
Before the LMAX Disruptor (Martin Thompson)
Before the
Name your performance technology du jour.
Just plain old java is required.

7. Obstacles Lack of Visibility / Tools The right monitoring is
Expensive
Only available in some environments
Lack of Expertise Only a small % of Java developers have the expertise
Mindset “Premature Optimization is the root of…..”

8. A Story and a Demo

9. Manual Call Stack Sampling
Apply load
Take about 4 dumps, a few seconds between each dump.
if you see a particular something that you could fix….
...and it shows up on two+ stacktraces, ones that are actually under load,
...then it is worth fixing.

10. Manual Call Stack Sampling
Three Books, two of them have been read
Partial Endorsement: Java Performance, The Definitive Guide Scott Oaks
Partial Endorsement: Java Performance, Charlie Hunt
Full Endorsement: Building Better Applications, Michael Dunlavey mathematical explanation

11. Less is More
I’m not suggesting to learn more about trouble shooting Java monitors/locks
...although that’s not a bad idea.

12. Less is More Limit what you look at in the thread dump. Less.
Production: Only consider threads in your package space
Test: Same, but also
Only 3 threads of load
Every SOA-service-sized component (or larger) must be load tested during development

13. Obstacles - Revisited
Lack of Visibility / Tools Use plug-it-in-now tools for all JVMs running in your world
Lack of Expertise Need a “Starting Point” -- a curriculum, the book I’m working on: Working title: JVM Performance Troubleshooting
Mindset ...that remains to be seen.

14. The End
Erik Ostermueller
@eostermueller