Thanks for the reply.
On 09/14/2015 03:39 PM, Michael Catanzaro wrote:
It is a non-ideal design. There is technical explanation in  (in
particular, comment #20) about why this was changed (TL;DR for running
X unprivileged), and the work that would be required to fix this.
We also need to bring back the nice transition between gnome-shell and
gdm (which disappeared due to this issue).
Yes, I understand the X server is now started non-root, but non-root X is functional
without keeping the gdm user session around for non-Gnome sessions.
Are you using NVIDIA's proprietary driver? So far, all of the
memory usage complaints I've seen have been from people using that
driver, which we obviously can't help with. :/
If you're using an open source driver, then please file a bug report.
The system is using the binary driver, but it is the only one that I leave on for
extended periods of time. I can try and replicate the issue on other systems with
open drivers now that I have a bug report to follow.