Move small memory instructions to advanced installation - installation.md

docs/installation.md

@@ -3,6 +3,7 @@
 ## Requirements
 
 - A fresh VM running Ubuntu `14.04 x64`
+- At least `1GB` of system memory ([workaround for 512MB machines](http://progrium.viewdocs.io/dokku/advanced-installation))
 
 Ubuntu 14.04 x64 x64. Ideally have a domain ready to point to your host. It's designed for and is probably best to use a fresh VM. The bootstrapper will install everything it needs.
 
@@ -29,24 +30,3 @@ As well, you may wish to customize your installation in some other fashion. or e
 - [Debian Package Installation Notes](http://progrium.viewdocs.io/dokku/getting-started/install/debian)
 - [Vagrant Installation Notes](http://progrium.viewdocs.io/dokku/getting-started/install/vagrant)
 - [Advanced Install Customization](http://progrium.viewdocs.io/dokku/advanced-installation)
-
-### VMs with only up to 512mb memory
-Having only 512mb of system-memory available for dokku and its containers, for example Digital Ocean's smallest machines, might result in unexpected errors, such as **! [remote rejected] master -> master (pre-receive hook declined)** during installation of NPM dependencies (https://github.com/npm/npm/issues/3867).
-
-To work around this issue, it might suffice to augment the linux swap file size to a maximum of twice the physical memory size.
-
-To resize the swap file of a 512MB machine to 1GB, follow these steps while in SSH within your machine:
-
-```shell
-cd /var
-touch swap.img
-chmod 600 swap.img
-
-dd if=/dev/zero of=/var/swap.img bs=1024k count=1000
-mkswap /var/swap.img
-swapon /var/swap.img
-free
-
-echo "/var/swap.img    none    swap    sw    0    0" >> /etc/fstab
-```
-Reference: https://www.digitalocean.com/community/tutorials/how-to-configure-virtual-memory-swap-file-on-a-vps