Comment 7 for bug 634487

I've done some more testing/poking and here's what I've found:

suite___ |arch| java_______ | result
lucid___ |32 |sun-java6-jdk | fail, system unreachable
lucid___ |32 |openjdk-6-jdk | fail, system unreachable
maverick |32 |sun-java6-jdk | bad performance, dpkg hang
maverick |32 |openjdk-6-jdk | bad performance, dpkg hang
lucid___ |64 |sun-java6-jdk | no failure
lucid___ |64 |openjdk-6-jdk | no failure
maverick |64 |sun-java6-jdk | no failure
maverick |64 |openjdk-6-jdk | no failure

the maverick tests were performed on 20100913 daily build (ami-48897c21/ami-46897c2f in us-east-1). The lucid tests were performed on ubuntu-lucid-10.04-amd64-server-20100827 (ami-1234de7b/ami-1634de7f in us-east-1).

more information on the 'result' column above:
 * fail, system unreachable: system crashes, ssh connection is terminated, system cannot be ssh'd to. The console log will eventually show the kernel trace as attached here.
 * bad performance, dpkg hang: upon installation, rsyslogd and the 'java' process mentioned above will peg CPU. The java pid is not killable. A kill -9 will simply send it to <defunct> (per 'ps' output). The dpkg process will not return, waiting for the java process.
 * no failure: class data sharing is not enabled on amd64, so the 'java -Xshare:dump' is not run, and apt installation proceeds and finishes. The preinstall script for jre-headless runs 'java -client -Xshare:dump -XX:PermSize=128m' only on i386 or sparc.

So, if you want to avoid this, you can just use an amd64 image. Additionally, for debugging, the maverick i386 images will be better as the system can be looked at (albeit painfully) while it is failing.