Difference between revisions of "RPi Java"

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(Created page with "Category:RaspberryPi == General tips == Some general tips about Java perfomace on Raspberry Pi. === System memory === Java loves memory. If you do not plan to use deskto...")
 
(General tips)
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=== Overclocking ===
 
=== Overclocking ===
 
Consider CPU overclocking with <code>sudo raspi-config</code> for considerable performance boost.
 
Consider CPU overclocking with <code>sudo raspi-config</code> for considerable performance boost.
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== Installing Java on Raspberry Pi ==
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=== Oracle Java 8 ===
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Oracle JDK 8 for ARM has JIT compiler and supports hard float point instructions. This is the fastest (1.5x-10x times faster than other JVMs) Java option for Raspberry Pi. Please note that Java 8 is still in beta stage and may be less stable than Java 7. You can install it on standard Raspbian system.
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* Visit [http://jdk8.java.net/fxarmpreview/ JDK 8 for ARM Early Access] web site, accept License Agreement, right click and copy download link.
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* Login to you Pi via ssh and run:
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<pre>
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# you download link from step 1
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wget http://www.java.net/download/JavaFXarm/jdk-8-ea-b36e-linux-arm-hflt-29_nov_2012.tar.gz
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tar zxf jdk-8-ea-b36e-linux-arm-hflt-29_nov_2012.tar.gz
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rm zxf jdk-8-ea-b36e-linux-arm-hflt-29_nov_2012.tar.gz
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sudo mv ./jdk1.8.0/ /opt/
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sudo chown root:root -R /opt/jdk1.8.0/
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sudo ln -s /opt/jdk1.8.0/ /opt/jdk8
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</pre>
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*Edit <code>sudo nano -w /etc/profile</code> and add these lines to the end of file:
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<pre>
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PATH="$PATH":/opt/jdk8/bin
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JAVA_HOME=/opt/jdk8
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</pre>
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* Logout and re-login via SSH. Run <code>java -version</code> to see if java is working. You should see something like:
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<pre>
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java version "1.8.0-ea"
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Java(TM) SE Runtime Environment (build 1.8.0-ea-b36e)
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Java HotSpot(TM) Client VM (build 25.0-b04, mixed mode)
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</pre>
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* Congratulations!

Revision as of 23:27, 22 February 2013


General tips

Some general tips about Java perfomace on Raspberry Pi.

System memory

Java loves memory. If you do not plan to use desktop enviroment / XBMC run sudo raspi-config select memory_split and decrease GPU memory to 16. You'll get more than 100 Mb of additional system memory.

Swap file

Do not swap! Manage your JVM memory consumption with -ms and -mx keys. If you absolutely have to swap move swap file (/var/swap) to USB HDD of fast flash drive because swapping to SD card is painfully slow. You can set swap size in /etc/dphys-swapfile config file.

Overclocking

Consider CPU overclocking with sudo raspi-config for considerable performance boost.

Installing Java on Raspberry Pi

Oracle Java 8

Oracle JDK 8 for ARM has JIT compiler and supports hard float point instructions. This is the fastest (1.5x-10x times faster than other JVMs) Java option for Raspberry Pi. Please note that Java 8 is still in beta stage and may be less stable than Java 7. You can install it on standard Raspbian system.

  • Login to you Pi via ssh and run:
# you download link from step 1
wget http://www.java.net/download/JavaFXarm/jdk-8-ea-b36e-linux-arm-hflt-29_nov_2012.tar.gz
tar zxf jdk-8-ea-b36e-linux-arm-hflt-29_nov_2012.tar.gz
rm zxf jdk-8-ea-b36e-linux-arm-hflt-29_nov_2012.tar.gz
sudo mv ./jdk1.8.0/ /opt/
sudo chown root:root -R /opt/jdk1.8.0/
sudo ln -s /opt/jdk1.8.0/ /opt/jdk8
  • Edit sudo nano -w /etc/profile and add these lines to the end of file:
PATH="$PATH":/opt/jdk8/bin
JAVA_HOME=/opt/jdk8
  • Logout and re-login via SSH. Run java -version to see if java is working. You should see something like:
java version "1.8.0-ea"
Java(TM) SE Runtime Environment (build 1.8.0-ea-b36e)
Java HotSpot(TM) Client VM (build 25.0-b04, mixed mode)
  • Congratulations!