ZRAM setup and configuration

I am trying to setup ZRAM on ubuntu 4.4 kernel. I can load and create zram based swap devices fine as you can see below. # apt-get install zram-config cat /proc/swaps Filename Type Size Used Priority /dev/sda3 partition 16638972 0 -1 /dev/zram0 partition 2036816 0 5 /dev/zram1 partition 2036816 0 5 /dev/zram2 partition 2036816 0 5 How can I make it work. I tried running memtester and load it with stress stress --vm-bytes $(awk '/MemFree/{printf "%d\n", $2 * 0.9;}' < /proc/meminfo)k --vm-keep -m 1 It does not look like it is being used. I notice that 'used' count in /proc/swaps does not bump at all. I even tried 'vmstat 1 100 ' while running stress and memtester and did not see any change in SO and SI. What am I missing? Thanks Russel