Just reporting that I'm experiencing this behavior too.
As soon as a program tries to allocate much memory on the heap and the system starts swapping, everything freezes
and I can't do anything but power-down.
Specs: 8GB of RAM, Ubuntu 12.04 amd64, linux 3.2.0-20-generic, encrypted swap and root fs.
Just reporting that I'm experiencing this behavior too.
As soon as a program tries to allocate much memory on the heap and the system starts swapping, everything freezes
and I can't do anything but power-down.
Specs: 8GB of RAM, Ubuntu 12.04 amd64, linux 3.2.0-20-generic, encrypted swap and root fs.