February 2015 - java-devroom - lists.fosdem.org

DevRoom Proposal: Jitsi Videobridge in Cryptoland: the adventures of a Java WebRTC video router on the road to supporting 1000s of video streams
by Lyubomir Marinov 06 Feb '15

06 Feb '15

Title: Jitsi Videobridge in Cryptoland: the adventures of a Java WebRTC video router on the road to supporting 1000s of video streams Abstract: In Jitsi Videobridge (https://jitsi.org/Projects/JitsiVideobridge) a WebRTC video conferencing router, encryption and packet signing were among the most expensive components in terms of CPU intensity. We therefore set out on a journey to optimize them as much as possible. We would like to share this journey with the Java FLOSS community. We are going to present a comparison we have made on the execution times of popular open source implementations of AES and SHA-1 in search of the best performer. Our reference implementations are provided by the pure-Java Bouncy Castle cryptography APIs. Our contenders are an assortment of widely-used Java and cross-platform C code: the SunJCE security provider optimized by Java Runtime Environment (JRE) 8, the Mozilla Network Security Services (NSS) libraries employed through the SunPKCS11 security provider and the OpenSSL Crypto library accessed with the help of the Java Native Interface (JNI). We're going to pit software against hardware in our examination how we can leverage the Advanced Encryption Standard New Instructions (AES-NI). We're going to look at the performance compromises of transferring bytes between Java and C. Can we beat Java's intrinsics? Will Java New/Non-blocking I/O (NIO) be better? Recording me on audio and/or video: The default is OK. Brief Bio: Lyubomir Marinov is the leading media developer at Jitsi (https://jitsi.org) He has been working on things like general performance and RTP-specific optimizations, audio/video encoding, rendering, mixing and processing for the past 8 years. Recently, Lyubomir is concentrating on solving issues related to video routing, speaker detection and the architecture of Jitsi Videobridge. Microblog URL: https://twitter.com/jitsinews

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DevRoom Proposal: Caciocavallo, or how we ported OpenJDK from embedded to cloud and still liked it
by Mario Torre 04 Feb '15

04 Feb '15

* Title Caciocavallo, or how we ported OpenJDK from embedded to cloud and still liked it * Abstract Caciocavallo has been one of the very first external projects to land in the OpenJDK repository and sponsored by the OpenJDK Porters Group. Named after a delicious cheese we're never tired of eating, it had the original purpose of refactoring the AWT peers to allow different implementations to be added to OpenJDK. The project evolved very quickly until it became itself a full implementation of AWT based on Swing with just enough abstraction to allow custom plugging into the Java2D system for rendering. As time passed, this characteristic was used to implement a GUI testing framework running on offscreen buffers to avoid the usual problems of focus stealing and random mouse moving that plague every other GUI testing framework (here everything is emulated!), and finally a full Web based backend to allow application to run remotely but still be visible on the local screen. This talk will cover the progress we have done over the years, we will show how easy is to implement a new backend and how this project could be used to give Wayland support to OpenJDK. We will show the testing framework and finally we will discuss about WebJDK, an idea to give more web oriented functionality to OpenJDK and use the web backend to enable fully cloud based applications. * Recording me on audio and/or video Yes, * Speakers Mario Torre, Red Hat, Inc. Roman Kennke, Red Hat, Inc. -- pgp key: http://subkeys.pgp.net/ PGP Key ID: 80F240CF Fingerprint: BA39 9666 94EC 8B73 27FA FC7C 4086 63E3 80F2 40CF Java Champion - Blog: http://neugens.wordpress.com - Twitter: @neugens Proud GNU Classpath developer: http://www.classpath.org/ OpenJDK: http://openjdk.java.net/projects/caciocavallo/ Please, support open standards: http://endsoftpatents.org/

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Free Java DevRoom: IcedTea-Web goes offline and beyond ; tallk proposal
by Jiri Vanek 04 Feb '15

04 Feb '15

Title: IcedTea-Web goes offline and beyond Abstract: Future of java applets and javaws is dark. Chrome have already cut down NPAPI. Most of the banks moved from java to javascript for they internet banking. The javaws will suffer a lot by introducing jigsaw modules. What is remaining? The "physical applets" of course! Seriously - the "killing" feature of applets is that they do not work offline. But similarly to javaws - they can! IcedTea-Web is now removing this boundaries, and what more, it will also allow you to detach applet out from browser - by jnlp shortcut, or by lunching html page by javaws directly. Apart of this, ITW is now JDK independent and you can run those features on any OpenJDK, even on Oracle or IBM JDKs. And except serving you web application comfortably online, ITW allows you to lock this application - even "signed ones" in sandbox. And of course there is Jogamp project - the awt-less plugin - How I wish to see it merged upstream!-) *** Long story short, more security and much much more freedom *** A/V recording: Ashamed, but Ok ET: 30 min + demos. Speaker: Jiri Vanek Most of the time cooking coffee for rest of Red Hat's OpenJDK team. Except this, maintaining OpenJDK for Fedora, developing ITW and trying to contribute to any open source stumbled over.

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Shenandoah - Project overview
by Christine Flood 04 Feb '15

04 Feb '15

Title: Shenandoah - Project overview Abstract: Garbage Collection pauses make it hard for Java applications to meet quality of service guarantees. No matter how fast your application processes requests, a 30 second GC pause is going to ruin any guarantees you might want to make. Shenandoah is a new GC algorithm designed to address this issue. We take a simple approach that allows us to do more work while your Java program is running so we can substantially reduce the time the JVM is paused. Our goal is to be able to garbage collect 100gb+ heaps in under 10ms. This talk will focus on the current status of the project, the goals we've met so far, and what we are hoping to achieve in the coming year. We might even share some performance numbers. Speakers: Christine H. Flood, Roman Kennke, Red Hat Inc. Christine H, Flood was part of the design team that brought you G1 and the parallel collector. She has 20+ years experience in programming language design and implementation. She's thrilled to be working for Red Hat on free and open software. Roman Kennke is a long time free Java (and Software) activist, originally involved in GNU Classpath since 2004, later participated in opening OpenJDK and since then is regular contributor to several parts of OpenJDK (AWT/Swing, general class library, lately Hotspot). After finishing Diploma in 2007 he was employed by aicas, who are building a hard realtime capable Java VM. During 2009 and 2010 worked for Sun Microsystems on Java Webstart. After a short period as contractor for JP Morgan, he's now a Prinipal Software Engineer at Red Hat, where he used to work on Thermostat, the Zero and Shark port of OpenJDK, and currently on the Shenandoah GC.

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ARM microJIT slides
by Edward Nevill 04 Feb '15

04 Feb '15

Hi all, I have put my slides at http://openjdk.linaro.org/arm32jit/fosdem15.pdf A binary of the JIT for R. PI is available at http://openjdk.linaro.org/arm32jit/images/arm32jit.tgz If anyone wants to try it, let me know of any problems etc. And check out http://connect.linaro.org/hkg15/ next week for any news! Many thanks to Mario and the team for making it a great Java devroom this year. The quality of the presentations was excellent. All the best, Ed.

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Dev Room Proposal: "cache2k, Java caching turbo charged"
by Jens Wilke 04 Feb '15

04 Feb '15

Title: cache2k, Java caching turbo charged Abstract: The development of cache2k has two streams: It is a robust cache implementation and provides features we miss from other products, on the other hand it is a research area to try out new caching algorithms and implementations to achieve the best performing in-memory Java cache that is available today. The talk will start with some real-world scenarios and challenges and how the cache can help, making it the pivotal point in an application to manage data resources and provide them on time. The second part of the talk will be about modern and adaptive caching algorithms and why you should not implement yet another "LRU cache" by yourself. This talk should encourage to use more caching to speed up applications and, of course, to hack and improve existing caching products. There is still much to achieve! Recording me on audio and/or video: acceptable under a CC-BY-2.0 license Speaker Bio: Jens Wilke is a coding veteran and part-time entrepreneur in a boutique software engineering company in Munich. In ancient times jens worked on many different projects, from embedded systems up to software for the IBM mainframe, in startups and in "legacy" companies. He is enthusiastic about improving performance, within developer teams as well as in complex software systems. Links: http://cache2k.org http://cruftex.net Cheers, Jens -- "Everything superfluous is wrong!" // Jens Wilke - headissue GmbH - Germany \// http://www.headissue.com

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DevRoom Proposal: Sustaining the zero assembler port in OpenJDK: An inside perspective of CPU specific issues.
by Severin Gehwolf 03 Feb '15

03 Feb '15

* Title Sustaining the zero assembler port in OpenJDK: An inside perspective of CPU specific issues. * Abstract OpenJDK comes with a zero assembler port called Zero. Back in 2009 when Zero was originally developed by Gary Benson, OpenJDK was available only on x86, x86_64 and SPARK. Despite recent JIT ports, such as the AArch64 and ppc/aix port, Zero still remains relevant for many Linux distributions. For example, at Red Hat we build and use the OpenJDK zero variant on PPC/PPC64 and s390/s390x. What's more it's a useful tool for getting new JIT ports built from source using free software. This talk will give a brief summary what Zero is and how it works. It will cover some of the recently discovered issues with sustaining the Zero port, how we try to catch them early and it will explain our experience with pushing fixes upstream. There will also be examples how this effort benefits the OpenJDK ecosystem as a whole. * Recording me on audio and/or video Yes * Speakers Severin Gehwolf, Red Hat, Inc. Severin Gehwolf a is a Software Engineer at Red Hat. Currently he is a member of the OpenJDK team primarily working on OpenJDK tooling and the zero assembler hotspot port. Photo link: http://www.gravatar.com/avatar/031db269afe97065baead22ce42e71bd Blog: https://jerboaa.wordpress.com/

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DevRoom Proposal: Packed Objects, Object Layout & Value Types - a Survey
by Volker Simonis 02 Feb '15

02 Feb '15

Title: Packed Objects, Object Layout & Value Types - a Survey Abstract: Java is often criticized for its lack of supporting C-style structs. This makes it hard to efficiently implement certain type of data structures (like for example arrays of small objects) in Java. However, recently there have been several different approaches which try to address this problem. My talk will briefly introduce "Packed Objects" [1], an extension available in IBM's Java SDK 8, "Object Layout" [2], a layout-optimized Java data structure package proposed by Azul Systems and Value Types [3][4], an OpenJDK proposal for immutable, reference-free value objects. I will describe the commonalities and differences of the three approaches and explain how they can improve the memory overhead and locality of Java objects. [1] http://www.oracle.com/technetwork/java/jvmls2013sciam-2013525.pdf [2] http://objectlayout.org/ [3] http://openjdk.java.net/jeps/169 [4] http://cr.openjdk.java.net/~jrose/values/values-0.html Bio: Volker Simonis works for SAP in the SAP JVM Technology group. He is an OpenJDK contributor from the very beginning and helped SAP and the SAP JVM team engage in the OpenJDK project. He's the project lead of the OpenJDK PowerPC/AIX porting project, a JDK8 committer and JDK9 reviewer. Recording me on audio and/or video is acceptable I'd like to get a 45min slot if possible. Thank you and best regards, Volker

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DevRoom Proposal: Open Heart Surgery: HotSpot Debugging at the OS Level
by Volker Simonis 02 Feb '15

02 Feb '15

Title: Open Heart Surgery: HotSpot Debugging at the OS Level Abstract: Debugging Java applications is comfortable and simple, but if you want to look beyond the Java horizon, you need special knowledge and and different tools. This interactive session shows you how to debug a running VM or analyze a VM core file with a native debugger like gdb. You will also learn how to use some of the more than 1,200 VM options to trace or modify the VM behavior. This knowledge can greatly help you identify, isolate and reproduce the root cause of hard VM crashes, and it can also be pure fun to see which actual machine instruction the CPU is executing for your Java code. Bio: Volker Simonis works for SAP in the SAP JVM Technology group. He is an OpenJDK contributor from the very beginning and helped SAP and the SAP JVM team engage in the OpenJDK project. He's the project lead of the OpenJDK PowerPC/AIX porting project, a JDK8 committer and JDK9 reviewer. Recording me on audio and/or video is acceptable This session requires a 45min slot. Thank you and best regards, Volker

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Re: VMFlexArray in OpenJDK
by Christopher Friedt 02 Feb '15

02 Feb '15

Hi I don't have Martin's contact info. I'm not sure if I've spelled his name correctly! He said that I should speak to him about possibly adding some of my change proposals for VMFlexArray to OpenJDK. Martin, if you receive the email, please email me back off-list. Thanks! © Sent from my Android

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