$ vncserver -geometry 1024x768
to start a vnc server with geometry 1024×768, which works well with Gnome 2 before. This also works for
However, after I connect to the vnc server, the resolution is not 1024×768. I change the geometry to other resolution and the actual resolution is not changed.
Gnome tries to resize the VNC session by setting the resolution last time restored.
So the solution is to set the Gnome 3 resolution inside the session in VNC in the Display settings of gnome. You can start it quickly by
$ gnome-control-center display
or find it out in the “Settings” for Gnome 3.