DaCapo benchmarks

This page describes how to get the Oracle-Sun JRE version 7 working on a disk image for use with ARM gem5. This will allow you to use the DaCapo benchmarks, which are on the Ubuntu image for gem5 ARM in the /benchmarks/dacapo directory.

Installing Oracle-Sun Java on an Ubuntu image for ARM gem5

Download the standard edition(SE) of Java 7 from Oracle. The SE version is the free version of Java available from Oracle. Make sure to get the headless version of the JRE for ARMv6/7 from Oracle. You may need to register with Oracle before being allowed to download. Once you have this, untar it.

• Create a mount point and mount the Ubuntu image:

sudo mkdir /mnt/ubuntu-gem5
sudo mount -o loop,offset=32256 arm-ubuntu-natty-headless.img /mnt/ubuntu-gem5
Setup the Java install directory and copy the Java directory over to your image:
cd /mnt/ubuntu-gem5/usr/lib
sudo mkdir jvm
sudo cp -a /path_to_jre/jre_folder /mnt/ubuntu-gem5/usr/lib/jvm

• Install Java:

//setup your directory
cd /mnt/ubuntu-gem5/usr/lib/jvm
ln -s ./jre_dir java-7-sun
cd /mnt/ubuntu-gem5
sudo bind -o /proc ./proc
sudo bind -o /dev ./dev
sudo bind -o /sys ./sys
sudo chroot .
exec ./bin/bash

//install Java
update-alternatives --install /usr/bin/java java /usr/lib/jvm/java-7-sun/bin/java 1
update-alternatives --install /usr/bin/keytool keytool /usr/lib/jvm/java-7-sun/bin/keytool 1

//setup .jinfo file
echo "name=java-7-sun" > .java-7-sun.jinfo
echo "alias=java-7-sun" >> .java-7-sun.jinfo
echo "priority=1" >> .java-7-sun.jinfo
echo "section=non-free" >> .java-7-sun.jinfo
echo "jre java /usr/lib/jvm/java-7-sun/bin/java" >> .java-7-sun.jinfo
echo "jre keytool /usr/lib/jvm/java-7-sun/bin/keytool" >> .java-7-sun.jinfo

//update java alternatives
update-java-alternatives -s java-7-sun

Once you have unmounted the image, you should be able to run Java with this disk image. Boot this image on gem5 and from the terminal type java -version to verify the Java version on your image.