I think you can make BD if you set enough swap space

something like 

modprobe zram
echo 2000000000 > /sys/block/zram0/disksize
mkswap /dev/zram0
swapon /dev/zram0

for 2 gb swap on 6 gb ram machine (usually pure 32 bit kernel can't see more than 4gb, but PAE kernel can, and you might have 64 bit kernel with 32-bit user apps/libs - thus 4 gb address space per process, and access to all physacal ram and 64-bit kernel optimizations and 64/32 bit x86 kvm!)