My appartement is under the roof and on really hot days I want to flee somewhere cold with access to my main-computer. Network access via dlan (with about 5-15MBit/s)

As we are using Unity3D/Windows in my day-job,...using Remote Desktop (win-host <-> win-client) makes quite a decent job and I used it the last two years from time to time.

But as my OS of choice is linux I needed a good alternative for linux.

X2Go seemed to be a good candiate here but lacks using opengl based applications.

SSH with X11 forwarding kind of worked but ultra slow on gl-based applications. Reminded me a bit on the good old C64-Textadventure with some turtle-graphics that took some time to be painted (like in The Hobbit):

# connect
ssh -X -Y SERVER

I found some hints the virtualgl can help with that. I'm not describing the steps needed. Follow these steps:
https://gist.github.com/cyberang3l/422a77a47bdc15a0824d5cca47e64ba2

In this you install virtualgl on the host (server) and a TurboVNC-server. You tell the TurboVNC what XSession to start (e.g. ubuntu-mate) and also tell that this session should be started via vglrun.

That was actually all pretty straight forward. But at the beginning there was no performance gain at all. In my special case the NVidia-Driver on the host was the problem. I had to add an option to /etc/X11/xorg.conf:

 Option         "HardDPMS" "true"

After this you just need to ssh into your account you want to share via vnc and start the TurboVnc-Server:

/opt/TurboVNC/bin/vncserver

This will indicate what display it will be working on. (e.g. :1 you need to remember this) You can now log out. On your client. Connect to TurboVNC:

/opt/TurboVNC/bin/vncviewer

Type in the host plus the display: e.g. 192.168.1.60:1 Login and that's it.

Some useful links: