Magneto is the tool, which informs you when updates are available. You can also launch Sulfur from the context menu (see picture). It is splitted into several packages. E.g., some of them are for Gnome/KDE integration.
If your System is up to date, then a greenish shieldsymbol appears in the taskbar. From time to time Magneto tries to connect to the Sabayon-Server to look for updates. If updates are available, Magneto changes the green symbol to a yellow one and displays a notification.
If you doubleclick on the yellow Symbol, a small window appears which shows you the available updates. You can also directly start Sulfur here. After the completion of the update process, Magneto is displaying a corresponding Notification and changes its symbol back to the green one. This means that all is ok now.
You can disable automatic updates by rightclicking on Magnetos symbol if you need full control over Sulfur and the Repository.
Only one program (this includes you too) at time can have access to the Repository and the update and installation processes. So if Magneto interferes with workflow, then you can also completely stop Magneto from the context menu.