Changes

!ProcessorVersion

!Development Kit version!Notes

|i1.0.MX6 Cortex-A90|Nov 2019|[[Axel_Embedded_Linux_Kit_(XELK)#XELK_4.0.0|XELK 4.0.0]]|i.MX6 DualLite SOC version|-|i.MX6UL Cortex-A7|Nov 2019|, [[AXEL_ULite_and_SBC_Lynx_Embedded_Linux_Kit_(XUELK)#XUELK_2.0.1.2F2.0.2.2F2.0.3|XUELK 2.0.3]]| i.MX6 Ultra Lite SOC version

Nowadays the Java programming language is more and more used for creating embedded application taking advantages from the popular and powerful programming language like [https://en.wikipedia.org/wiki/Java_(programming_language) Javaprogramming language] has been mainly used to develop business server side application. On the latest years it can be used on embedded devices too, thanks both to the constantly increasing processing power of embedded microprocessors and to the optimization of Java Virtual Machines === Java Virtual Machine ===There are many different JVM that can run on ARM platform: the JVM let you to run your Java application on an Embedded platform like the DAVE's [[:Category:SBC-AXEL | SBC-AXEL]] and [[:Category:SBC_Lynx | SBC-Lynx]]platforms.

As well knownIn this Application Note, we would like to explore some of the most popular Java Virtual Machines and measure their performances on the embedded platform. The different JVMs performance results let the user to target which JVM can be the best selection for running its Java code. ==== ZeroVM====The [https://openjdk.java.net/projects/zero/ ZeroVM] JDK version has to be taken into account if used on some JVM: this version - used for example on ''OpenJDK 8'' and ''AdoptOpenJDK 8'' - gives output results '''really less performing''' then the others VMs. It should be considered - infact - that ''OpenJDK Zero VM is an interpreter only JVM''. It's easier to port because it has no architecture specific assembly code but, on the other hand, it's not performant because it has no architecture specific assembly code. == Available Java Virtual Machines ==There's tons of JVM available in the market, both commercials and free/opensource ones: the JVM listed below have been selected from the main Java players in the market. Obviously the <b>Oracle JDK</b> is the reference one due to the original Java project started by [https://en.wikipedia.org/wiki/Java_(programming_language) Sun Microsystems] and acquired by [https://en.wikipedia.org/wiki/Sun_acquisition_by_Oracle Oracle] on 2010. Historically Sun/Oracle provides different flavors of their JVM, depending on the target host (desktop vs server vs embedded. [https://www.oracle.com/java/technologies/javase-embedded-downloads.html Oracle Java SE Embedded] was the flavor targetting embbedded market, but Oracle announced that '''Java 8''' is ''the final major Oracle Java SE Embedded Product''. [https://blogs.oracle.com/java-platform-group/convergence-of-oracle-java-se-embedded-with-oracle-jdk Here] descriptionthe blog announce:

Java is a general-purpose programming language that is class-basedAccordingly, object-orientedstarting with JDK 9, and designed Oracle doesn't plan to have as few implementation dependencies as possibleoffer a separate "Oracle Java SE Embedded" download. It is intended to let application developers write once In other words, run anywhere: Oracle Java code can run on all platforms that support SE 8 Embedded is the final release series of the "Oracle Java without SE Embedded" product. New features in JDK 9 obviate the need for recompilation.Java applications are typically compiled it to bytecode that can run on any Java virtual machine (JVM) regardless of the underlying computer architecturebe a separate product.

For the ''The Oracle Java License'', please find more information on Oracle [https://java.com/en/download/release_notice.jsp Java web site]. Newest JVM based on Java 9, 10, 11, 12 and 13 can be found from the OpenJDK JVM players. === Java Selection of embedded Virtual Machine ===There are many different JVM that can run on ARM platform Here below the list of JVMs compared in the tests and the binary download sites: {| class="wikitable" border="1"! Java Virtual Machine! JDK version! VM version!Notes|-| [https://www.oracle.com/technetwork/java/javase/downloads/jdk8- like downloads- let you to run your 2133151.html Oracle JDK]| 8u211| Java application on HotSpot(TM) Client VM (build 25.211-b12, mixed mode)||-| OpenJDK (*)| 1.8.0_102| OpenJDK Zero VM (build 25.102-b14, interpreted mode)| [https://openjdk.java.net/projects/zero/ ZeroVM]|-| [https://github.com/AdoptOpenJDK/openjdk8-binaries/releases/download/jdk8u232-b09/OpenJDK8U-jdk_arm_linux_hotspot_8u232b09.tar.gz AdoptOpenJDK]| 1.8.0_232| OpenJDK Zero VM (AdoptOpenJDK)(build 25.232-b09, interpreted mode)| [https://openjdk.java.net/projects/zero/ ZeroVM]|-| [https://cdn.azul.com/zulu-embedded/bin/zulu8.42.0.195-ca-jdk1.8.0_232-linux_aarch32hf.tar.gz ZuluCommunity]| 8u232| OpenJDK Client VM (Zulu8.42.0.195-CA-linux_aarch32hf) (build 25.232-b195, mixed mode, Evaluation)||-| [https://github.com/AdoptOpenJDK/openjdk11-binaries/releases/download/jdk-11.0.5%2B10/OpenJDK11U-jdk_arm_linux_hotspot_11.0.5_10.tar.gz AdoptOpenJDK]| 11.0.5| OpenJDK Server VM AdoptOpenJDK (build 11.0.5+10, mixed mode)||-| [https://download.bell-sw.com/java/11.0.5+11/bellsoft-jdk11.0.5+11-linux-arm32-vfp-hflt.tar.gz LibericaJDK]| 11.0.5-BellSoft| OpenJDK 32-Bit Server VM (build 11.0.5-BellSoft+11, mixed mode)||-| [https://cdn.azul.com/zulu-embedded/bin/zulu11.33.21-ca-jdk11.0.4-linux_aarch32hf.tar.gz ZuluCommunity]| 11.0.4| OpenJDK Client VM Zulu11.33+21-CA (build 11.0.4+10-LTS, mixed mode)||-|}(*) We do not provide a download URL for OpenJDK 1.8.x because it has been build with standard recipe provided with DAVE's Embedded platforms. Development Kits === Licensing ===Each JVM has a proper licensing model and this has to be taken into account:

In this Application Note, we would like to explore some of * Oracle: the most popular [https://www.oracle.com/downloads/licenses/javase-license1.html Java Virtual Machines license] agreement should be accomplished in order to use and measure their performances on the embedded platformevaluate it* OpenJDK, AdoptOpenJDK: [https://adoptopenjdk.net/about.html GPLv2]* Zulu: see [https://www.azul.com/products/zulu-community/ Zulu Community] (''free download and uses without restrictions'', cit'')''* BellSoft: [https://bell-sw.com/pages/java-11.0. The different JVMs performance results let the user to target which JVM can be used 5%20for%20Embedded/ Liberica JDK for running its Java code in the better wayEmbedded] (''provided with no license restrictions'', cit.'')''

* <b><i>SciMark</i></b>: please read the [https://math.nist.gov/scimark2/credits.html credits] page about <b>National Institute of Standards and Technology (NIST)</b> GPL license* <b><i>CaffeineMark</i></b>: according to the <b>Pendragon Software's CaffeineMark'''™''' ver. 3.0</b>** the test was performed without independent verification by Pendragon Software and that Pendragon Software makes no representations or warranties as to the result of the test === Test results ===The benchmarks have been run on the same platform and same cpu: the different JVMs was decompressed in the ''/home/root/java'' directory of the target and started manually. ==== XELK ====The following tests have been performed on [[:Category:SBC-AXEL | SBC-AXEL]] equipped with:* '''DXLM0193''' SOM * i.MX6 Dual Lite processor @ 792MHz* 1GB DDR* boot from SD card (u-boot, kernel and root file system) {| class="wikitable" border="1"! Java Virtual Machine! SciMark 2.0 (Composite Score)! CaffeineMark 3.0 (Overall score)|-| Oracle JDK 8| 69.37| 22673|-| OpenJDK 8 (*)| ''3.62''| ''605''|-| AdoptOpenJDK 8 (*)| ''3.44''| ''569''|-| ZuluCommunity 8| 69.14| 17237|-| AdoptOpenJDK 11| '''82.39'''| '''78111'''|-| LibericaJDK 11| '''82.55'''| '''77083'''|-| ZuluCommunity 11| 69.61| 17060|-|} (*) The ''interpreted'' [[XELK-AN-009:_Comparing_JVMs_(Java_Virtual_Machines)_on_i.MX6_family_processors#ZeroVM | ZeroVM]] JVM version explains the very poor performance  ==== XUELK ====The following tests have been performed on [[:Category:SBC_Lynx | SBC-Lynx]] equipped with:* i.MX6 Ultra Lite processor @ 528MHz* 512MB DDR* boot from SD card (u-boot, kernel and root file system) {| class="wikitable" border="1"! Java Virtual Machine! SciMark 2.0 (Composite Score)! CaffeineMark 3.0 (Overall score)|-| Oracle JDK 8| 28.75| 9426|-| OpenJDK 8 (*)| ''1.68''| ''257''|-| AdoptOpenJDK 8 (*)| ''1.55''| ''243''|-| ZuluCommunity 8| 29.26| 9482|-| AdoptOpenJDK 11| '''54.23'''| '''30268'''|-| LibericaJDK 11| '''54.46'''| '''27261'''|-| ZuluCommunity 11| 29.16| 9200|-|} (*) The ''interpreted'' [[XELK-AN-009:_Comparing_JVMs_(Java_Virtual_Machines)_on_i.MX6_family_processors#ZeroVM | ZeroVM]] JVM version explains the very poor performance  For a detailed test command usage, please read carefully click on the [http''Expand'' link: <div class="mw-collapsible mw-collapsed"> <pre class="board-terminal">root@sbc-lynx:~/java# ls -ladrwxr-xr-x 10 root root 4096 Jan 8 22:29 .drwx------ 4 root root 4096 Jan 8 21:41 ..drwxr-xr-x 10 1000 1000 4096 Jan 8 22:15 adopt-jdk11.0.5drwxr-xr-x 5 1000 1000 4096 Jan 8 21:45 adopt-jdk8u232drwxrwxr-x 7 1000 1000 4096 Jan 8 21:55 bellsoft-jdk11.0.5drwxr-xr-x 3 root root 4096 Jan 8 21:53 benchmarkdrwxr-xr-x 10 1000 1000 4096 Jan 8 21:52 jdk1.8.0_211drwxrwxr-x 9 111 122 4096 Jan 8 21:49 zulu-jdk1.8.0_232drwxrwxr-x 10 111 122 4096 Jan 8 22:01 zulu-jdk11.0.4root@sbc-lynx:~/java# ls -la benchmark/drwxr-xr-x 3 root root 4096 Jan 8 21:53 .drwxr-xr-x 10 root root 4096 Jan 8 22:29 ..drwxr-xr-x 2 root root 4096 Jan 8 21:43 Caffeine-rwxr-xr-x 1 root root 34229 Jan 8 21:53 scimark2lib.jarroot@sbc-lynx:~/java#</pre> Here below an example of SciMark benchmark started for OracleJDK on '''i.MX6DL''': <pre class="board-terminal">root@imx6qxelk:~/java# ./wwwjdk1.8.benchmarkhq0_211/bin/java -cp .ru/cm30benchmark/disclaimscimark2lib.jar jnt.scimark2.commandlineSciMark 2.0a Composite Score: 69.html37463986126829FFT (1024): 69.63592899407837SOR (100x100): 123.68132332709474Monte Carlo : 17.99165245491594Sparse matmult (N=1000, nz=5000): 50.866191316811516LU (100x100): 84.69810321344092 java.vendor: Oracle Corporationjava.version: 1.8.0_211os.arch: armos.name: Linuxos.version: 4.9.11-xelk-4.0.0root@imx6qxelk:~/java#license license agreement] for running </pre> and the same JVM on the '''i.MX6UL''': <pre class="board-terminal">root@sbc-lynx:~/java# ./jdk1.8.0_211/bin/java -cp ./benchmark/scimark2lib.jar jnt.scimark2.commandline SciMark 2.0a Composite Score: 28.752359792101156FFT (1024): 24.74240503907121SOR (100x100): 52.136229862882686Monte Carlo : 7.4006247447847375Sparse matmult (N=1000, nz=5000): 24.794189606277396LU (100x100): 34.68834970748977 java.vendor: Oracle Corporationjava.version: 1.8.0_211os.arch: armos.name: Linuxos.version: 4.1.15-xuelk-2.0.3root@sbc-lynx:~/java#<b/pre>Pendragon Software Then, an example of Caffeine benchmark on '''i.MX6DL'''s CaffeineMark: <pre class="board-terminal">root@imx6qxelk:~/java# ./jdk1.8.0_211/bin/java -cp ./benchmark/Caffeine CaffeineMarkEmbeddedAppSieve score = 12204 (98)Loop score = 46042 (2017)Logic score = 22955 (0String score = 29983 (708)Float score = 21900 (185)Method score = 16041 (166650)Overall score = 22673root@imx6qxelk:~/java#</pre> and the same JVM on the '''™i.MX6UL''' ver: <pre class="board-terminal">root@sbc-lynx:~/java# ./jdk1.8. 30_211/bin/java -cp ./benchmark/Caffeine CaffeineMarkEmbeddedAppSieve score = 6359 (98)Loop score = 14088 (2017)Logic score = 11336 (0)String score = 11944 (708)Float score = 7008 (185)Method score = 8253 (166650)Overall score = 9426root@sbc-lynx:~/java#</pre> </bdiv> == Copyright and Trademark Information == Java™ and HotJava™ are trademarks of Sun Microsystems, Inc. and refer to Sun's Java programming language and HotJava browser technologies. Java™ and OpenJDK™ are trademarks or registered trademarks of Oracle and/or its affiliates. Zulu Community™ is a trademark and Copyright © of Azul Systems, Inc.

== JVMs ==The following Java Virtual Machines have been selected for the main Java player in the market. Obviously the <b>Oracle JDK</b> Liberica is the reference one due to the a Copyright of © BellSoft LTD

The [https://www.oracle.com/downloads/licenses/javase-license1.html Java license] agreement should be accomplished in order to use CaffeineMark™ benchmark is a trademark and evaluate the OracleCopyright © of Pendragon Software

* [https://wwwAdoptOpenJDK is a community of Java User Group (JUG) members, Java developers and vendors including Azul, Amazon, GoDaddy, IBM, jClarity, Microsoft, New Relic, Pivotal and Red Hat.oracle.com/technetwork/java/javase/downloads/jdk8-downloads-2133151.html Oracle JDK SE 8]