A bug has crept into the Icecream 1.0 release that makes the daemon crash on its first start after boot if /var/run is cleared (e.g. it's tmpfs-mounted by systemd). This in practice means that on such systems Icecream does not work unless started manually. So in case your compiles have felt tad a bit slower recently, upgrade to the just released version 1.0.1. If you run openSUSE, an online update with the fix has already been published.