Comment # 2 on bug 901132 from Antons Svedkijs

Use-Case: 

On VMs with calculation / read-only / load-balancing services there is no need
to reserve more space than it was needed vor installation + some more space for
logs and update cache (~1GB).

Update are important for security reasons.

But critical severity was a rash choice :) Sorry for that. I'll be carefull
next with severity choice.