I like to use DigitalOcean for trying out new web-applications and scripts. The cheapest plan comes at $5/month but provides only 512MB of memory. Adding a 1Gb swap memory is usually sufficient for temporary memory extensive needs. These is a short documentation on how to add the swap partition.
Adding a swap partition:
sudo dd if=/dev/zero of=/swap bs=1M count=1024 sudo mkswap /swap sudo swapon /swap
Making the partition persistent on system reboots:
sudo vi /etc/fstab # Add a line to tell the system to use the file /swap none swap sw 0 0
vfc_cache_pressure for VPS needs:
sudo vi /etc/sysctl.conf # Add the following at the bottom vm.vfs_cache_pressure = 50 vm.swappiness = 10
The detailed article about what each of the above commands do is available here.