$ export CLASSPATH=/usr/lib/jvm/java-1.4.2-gcj-1.4.2.0/lib/tools.jar
$ time gij -verbose:class com.sun.tools.javac.Main HelloWorld.java &> class.interp.log
real    0m9.633s
user    0m8.675s
sys     0m0.094s
$ time gij -verbose:class -Dgnu.gcj.precompiled.db.path=/usr/lib/eclipse/eclipse.db \
  com.sun.tools.javac.Main HelloWorld.java &> class.precomp.log
real    0m8.972s
user    0m8.761s
sys     0m0.113s
$ diff class.interp.log class.precomp.log > class.log.diff
$ sudo mv /usr/lib/eclipse/plugins/org.eclipse.jdt.core_3.1.0/jdtcore.jar.so \
          /usr/lib/eclipse/plugins/org.eclipse.jdt.core_3.1.0/jdtcore.jar.so.not
$ time gij -verbose:class com.sun.tools.javac.Main HelloWorld.java &> class.interp2.log
real    0m2.543s
user    0m2.430s
sys     0m0.111s
$ time gij -verbose:class -Dgnu.gcj.precompiled.db.path=/usr/lib/eclipse/eclipse.db \
  com.sun.tools.javac.Main HelloWorld.java &> class.precomp2.log
real    0m2.116s
user    0m2.014s
sys     0m0.097s