How to avoid [Errno 12] Cannot allocate memory errors caused by using subprocess module

If you are running out of memory, you may want to increase your swap memory. Or you might have no swap enabled at all. In Ubuntu (it should work for other distributions as well) you can check your swap by:

$sudo swapon -s

if it is empty it means you don’t have any swap enabled. To add a 1GB swap:

$sudo dd if=/dev/zero of=/swapfile bs=1024 count=1024k
$sudo mkswap /swapfile
$sudo swapon /swapfile

Add the following line to the fstab to make the swap permanent.

$sudo vim /etc/fstab

     /swapfile       none    swap    sw      0       0 

Source and more information can be found here.