an open source instrumentation tool for the hotspot...

Thermostat

An Open SourceInstrumentation Tool for theHotspot JVM

Severin Gehwolf, Red HatMario Torre, Red Hat

Developer Conference 2013

2/34 Severin Gehwolf & Mario Torre Feb 23, 2013

Agenda

● What is it exactly this Thermostat?● How does Thermostat work?● Current and upcoming features● Thermostat plug-ins 101● Demo/Hack Session

3

The Tool Explained(a.k.a. What is this tool exactly?)


What is Thermostat?

Monitoring

Diagnostics

Tuning

Profiling

OpenSource

OpenJDK


What is Thermostat?

Monitoring

Diagnostics

Tuning

Profiling

OpenSource

OpenJDK

Information Hub


What is Thermostat?

AS

JVM

OS


What is Thermostat?

AS

JVM

OS

Vertical Integration


What is Thermostat?

Local Remote Cluster Cloud?


What is Thermostat?

Horizontal Integration


Lines of Code

Source: https://www.ohloh.net/p/thermostat-monitoring-tool


Commits Per Month

Source: https://www.ohloh.net/p/thermostat-monitoring-tool

12

Current and Upcoming Features


Current Features

● CPU monitoring

● Memory usage

● GC invocations

● Thread monitoring

● Heap dump analysis

● Classloader information

● Numa


Upcoming Features

● Finish NUMA support● JVM tuning● Systemtap / oprofile backend● Memory leak & deadlock analysis● Eclipse client/IDE integration● Web client● Host / JVM issues overview● Open Shift deployment. Maybe?

15

Cool!How Does It Work?


Agent, Client, Storage Approach


How Does It Work?

Agents


How Does It Work?

Storage


How Does It Work?

Clients


Where Is The Data Coming From?

● JvmStat

● JMX

● /proc

● Systemtap

● Oprofile

● App Server


Where Is The Data Coming From?

● JvmStat

● JMX

● /proc

● Systemtap

● Oprofile

● App Server

At Present

In Future

22

Plug-in 101


The Basics (1)

● Extensible through plug-ins

● OSGi

● Write your own agent extensions

● Write your own client extensions

● plugin.xml file tells Thermostat about your new

bundles


Recall...

Agents


Agent Extensions

Numa

Backends


Storage Extensions

NumaDAO

DAOs


Client Extensions

InformationService

VmRef HostRef


The Basics (2)

● Backend's extend agents

● Data Access Objects (DAO) extend Storage

● InformationService's extend GUI

● Can bind UI to...

– HostRef (a specific host/agent)

– VmRef (a specific JVM)


plugin.xml<?xml version="1.0" ?><plugin> <commands> <command type="extends"> <name>gui</name> <bundles> <bundle>your-plugin-0.1-SNAPSHOT.jar</bundle> </bundles> </command> <command type="provides"> <name>hello</name> <description>Prints hello</description> <usage>hello</usage> <bundles> <bundle>your-hello-world-plugin-0.1-SNAPSHOT.jar</bundle> </bundles> <dependencies> <dependency>thermostat-client-core-0.6.0-SNAPSHOT.jar</dependency> </dependencies> </command> </commands></plugin>

30

Questions?


Why This New Tool?

● Scalability● Avoiding unwanted dependencies.● Written in Java, by Java devs, for Java devs.● Flexible data model● Developer ego (This is joke. You laugh

now).

32

Demo/Hack Session Time!


References

● Homepage: http://icedtea.classpath.org/thermostat/

● Code: http://icedtea.classpath.org/hg/thermostat

● Mailing list: http://icedtea.classpath.org/mailman/listinfo/thermostat

● IRC: #thermostat on freenode.net

● Duke images from around the net

● http://jroller.com/neugens/entry/thermostat_scheduler_plugin_a_walk

34

Thank You!Kudos to Mario and Omair for providing most of the plug-in code!

an open source instrumentation tool for the hotspot...

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