javantura v4 - jvm++ the graalvm - martin toshev

JVM++: The Graal VM

Martin Toshev

@martin_fmi

Special thanks to Thomas Wuerthinger and Oracle Labs for inspiring this presentation …

Who am ISoftware consultant (CoffeeCupConsulting)

BG JUG board member (http://jug.bg)

OpenJDK and Oracle RBDMS enthusiast

Twitter: @martin_fmi

http://jug.bg/

Agenda

• Overview of the Graal VM

• Building and managing Graal

• Performance benchmarks

• Future directions

Overview of the Graal VM


Some background …

static compilation vs dynamic compilation

static compiler

source code (e.g. JVM bytecode)

dynamic compilerruntime

machine code

runtime

source code (e.g. JVM bytecode)

machine code


• Graal is a new JIT (Just-in-Time) compiler for the JVM

• Brings the performance of Java to scripting languages (via the Truffle API)

• written in Java


• In essence the Graal JIT compiler generates machine code from an optimized AST rather than bytecode

• However the Graal VM has both AST and bytecode interpreters


• The Truffle API:

– is a Java API

– provides AST (Abstract Syntax Tree) representation of source code

– provides a mechanism to convert the generated AST into a GraalIR (intermediate representation)


• The Truffle API is declarative (uses Java annotations)

• The AST graph generated by Truffle is a mixture of control flow and data flow graph

• Essential feature of the Truffle API is the ability to specify node specializations used in node rewriting


• The Truffle API is used in conjunction with custom annotation processor that generates code based on the Truffle annotations used in the interpreter classes

Truffle Interpreter

javac

Annotation processor

Compiled Interpreter

Generated Interpreter source code


• General architecture:

HotSpot VM (C++)

Graal (Java)

Truffle (Java) Java Other JVM language

JavaScript Ruby ROther interpreted

language

Graal <–> Hotspot adapter (C++, Java)

Maxine VM (Java)

Graal <–> Maxine adapter (Java)


• Let’s see, for example, how a JavaScript interpreter works in Graal …


HotSpot VM (C++)

Graal (Java)



language


Run JavaScript file: app.js


HotSpot VM (C++)

Graal (Java)



language


JavaScript Interpreter parses app.js and converts it to Truffle AST


HotSpot VM (C++)

Graal (Java)



language


The app.js Truffle AST is converted to Graal IR (AST)


HotSpot VM (C++)

Graal (Java)



language


The Graal VM has bytecode and AST interpreters along with a JIT compiler(optimizations and AST lowering is performed to generate machine code and perform partial evaluation)


HotSpot VM (C++)

Graal (Java)



language


When parts of app.js are compiled to machine code by the Graal compiler the compiled code is transferred to Hotspot for execution by means of Hotspot APIs and with the help of a Graal – Hotspot adapter interface


HotSpot VM (C++)

Graal (Java)



language


Compiled code can also be deoptimized and control is transferred back to the interpreter (e.g. when an exception occurs, an assumption fails or a guard is reached)


• Optimizations done on the Graal IR include:

– method inlining– partial escape analysis– inline caching– constant folding– arithmetic optimizations and others …


• Currently supported languages include:

– JavaScript (Graal.JS)– R (FastR)– Ruby (RubyTruffle)– Experimental interpreters for C, Python, Smalltalk, LLVM

IR and others …

(some are not open-sourced yet as of the time of this presentation)


• The SimpleLanguage project provides a showcase on how to use the Truffle APIs

Source file Parser Truffle AST Graal VM

Building the Graal VM


• The Graal VM interoperates with JEP 243: Java-Level JVM Compiler Interface

• In that regard two modes of operation are supported – via the Graal VM or via the JVMCI (JVM Compiler Interface)


• Early access builds of Graal available for download

• You can build Graal on any supported platform (Windows, Linux, MacOS, Solaris) from source code


git clone https://github.com/graalvm/mx.git

export PATH=$PWD/mx:$PATH

git clone https://github.com/graalvm/graal-core.git

cd graal-core

mx --vm graal build

mx vm

Building the Graal VM• The MX tool is a Python (2.7) tool that manages the Graal

projects and allows to: - update sources and run JUnit tests and benchmarks;

- builds (sub)projects (Java and C++ sources can be built separately);

- runs VM tools (such as IGV or c1visualizer) that can aid development of Graal or language interpreters;

- can be used to generate IDE project files for Graal development (support for Eclipse and NetBeans)

The Graal VMdemo

Performance benchmarks

Performance benchmarks

• According to various JVM benchmarks such as SPECjvm2008 and Scala Dacapo the Graal compiler positions between the client and server JVM compilers(source: One VM to Rule Them All, Thomas Wuertinger)

• In general Truffle interpreters provide much better performance for some dynamic languages

Performance benchmarks• Graal.JS – shows improvement of 1.5x in some cases

with a peak of 2.6x compared to V8 (running Google Octane’s benchmark)

• RubyTruffle – shows improvements between 1.5x and 4.5x in some cases with a peak of 14x compared to JRuby

• FastR - shows improvements between 2x and 39x in some cases with a peak of 94x compared to GnuR

(source: One VM to Rule Them All, Thomas Wuertinger)

Future directions

Future directions

• Graal provides an extensible framework for researching and experimenting with other compiler optimizations

• In that regard new types of compiler optimizations that address runtime behavior in certain scenarios may be introduced in the VM

Future directions• Graal provides an extensible framework for creating

language interpreters further simplified by the Truffle API

• In that regard more languages can be introduced that run in the Graal VM

• Currently existing languages that compile to bytecode may support Truffle in the future

Future directions

• Graal provides an extensible framework for different types of operating systems and CPU architectures

• In that regard more CPU architectures and operating systems might be supported by Graal

Thank you !

Q&A

ReferencesGraal Project

http://openjdk.java.net/projects/graal/

Graal - A New Just In Time Compiler for the JVM

http://www.oracle.com/technetwork/oracle-labs/program-languages/overview/index.html

Graal VM: GitHub repositories

https://github.com/graalvm

http://openjdk.java.net/projects/graal/

http://www.oracle.com/technetwork/oracle-labs/program-languages/overview/index.html

https://github.com/graalvm

ReferencesGraal - A Bytecode Agnostic Compiler for the JVM, Thomas Wuerthinger, JVM Language Summit

http://medianetwork.oracle.com/video/player/1113230360001

Graal and Truffle: One VM to Rule Them All

http://www.slideshare.net/ThomasWuerthinger/graal-truffle-ethdec2013?qid=848a4965-9768-40d5-b167-ccd8eb7d1659&v=&b=&from_search=2


http://www.slideshare.net/ThomasWuerthinger/graal-truffle-ethdec2013?qid=848a4965-9768-40d5-b167-ccd8eb7d1659&v=&b=&from_search=2

ReferencesGraal and Truffle: Modularity and Separation of Concerns as Cornerstones for Building a Multipurpose Runtimehttp://www.slideshare.net/ThomasWuerthinger/2014-0424-graal-modularity?qid=0e86ed21-0b8f-4087-9212-68f76546d674&v=&b=&from_search=4

Dynamic Compilation - Thomas Wuerthingerhttps://www.youtube.com/watch?v=RLsG2kE1EMIhttps://www.youtube.com/watch?v=U_QpToYLsO0

JVMLS 2012: Graalhttp://medianetwork.oracle.com/video/player/1785432492001

http://www.slideshare.net/ThomasWuerthinger/2014-0424-graal-modularity?qid=0e86ed21-0b8f-4087-9212-68f76546d674&v=&b=&from_search=4

https://www.youtube.com/watch?v=RLsG2kE1EMI

https://www.youtube.com/watch?v=U_QpToYLsO0


ReferencesGraal Tutorial at CGO 2015 by Christian Wimmer

http://lafo.ssw.uni-linz.ac.at/papers/2015_CGO_Graal.pdf

Writing a language in Truffle: Part 1 - Using Truffle and Graal

https://cesquivias.github.io/blog/2014/10/13/writing-a-language-in-truffle-part-1-a-simple-slow-interpreter/

Writing a language in Truffle: Part 2 - Using Truffle and Graal

http://cesquivias.github.io/blog/2014/12/02/writing-a-language-in-truffle-part-2-using-truffle-and-graal/

http://lafo.ssw.uni-linz.ac.at/papers/2015_CGO_Graal.pdf

https://cesquivias.github.io/blog/2014/10/13/writing-a-language-in-truffle-part-1-a-simple-slow-interpreter/

http://cesquivias.github.io/blog/2014/12/02/writing-a-language-in-truffle-part-2-using-truffle-and-graal/

ReferencesGraal publications, JKU, Linz

http://ssw.jku.at/Research/Projects/JVM/Graal.html

Truffle publications, JKU, Linz

http://ssw.jku.at/Research/Projects/JVM/Truffle.html

http://ssw.jku.at/Research/Projects/JVM/Graal.html

http://ssw.jku.at/Research/Projects/JVM/Truffle.html

ReferencesR as a citizen in a Polyglot world: The promise of the Truffle framework

http://user2015.math.aau.dk/presentations/112.pdf

Truffle/C Interpreter

http://www.manuelrigger.at/downloads/trufflec_thesis.pdf

Graal.JS - high-performance JavaScript on the JVM talk by Christian Wirth

https://www.youtube.com/watch?v=OUo3BFMwQFo

http://user2015.math.aau.dk/presentations/112.pdf

http://www.manuelrigger.at/downloads/trufflec_thesis.pdf

https://www.youtube.com/watch?v=OUo3BFMwQFo

javantura v4 - jvm++ the graalvm - martin toshev

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