Display is not refreshed unless mouse movement over time

Describe the bug Client connected with vncviewer and seems to start fine without issues, however, over time, the connection seems to stop updating the screen unless you move the mouse over the viewer screen. The setup is kiosk mode with Gnome and view only.

We are using it on a local lan, so just a couple switches on a 40g fiber network. We see traffic passing between the systems using tcpdump, but when the system stops updating, all VNC traffic stops - until you move the mouse over the viewer, then it kicks back up with traffic.

We suspected packet drops and tcp re-transmits, but have been assured by network team that there are no errors on the 40g switches or the ports the systems are connected to.

To Reproduce To reproduce, we just have to kill the connection with vncviewer and reconnect. Again, initially it will start fine, but over time will degrade.

The time it takes can be from 5 min to several hours.

Expected behavior We expect the viewing session to continue to update the screen for changes over the course of the connection

Screenshots Unfortunately, this is a classified environment, so I will not be able to provide screen shots, but I can get you the information you need.

Client (please complete the following information):

OS: RHEL 8.6 - Desktop is Gnome
VNC client: TigerVNC
VNC client version: 1.12.0-6
Client downloaded from: RedHat Sat Repo
Using vncviewer -via user@server :0

Server (please complete the following information):

OS: RHEL 8.6
VNC server: TigerVNC
VNC server version: 1.12.0-6
Server downloaded from: Redhat Sat Repo
Server was started using: /usr/bin/x0vncserver -display :1 -AcceptSetDesktopSize=0 -AcceptPointerEvents=0 -AcceptKeyEvents=0 -AlwaysShared

Additional context

Here is the xorg.conf we are using on the server side:

` Section "DRI" Mode 0666 EndSection

Section "ServerLayout" Identifier "TwinLayout" Screen 0 "metaScreen" 0 0 Option "AllowNVIDIAGPUScreens" "true" EndSection

Section "Monitor" Identifier "Monitor0" Option "DPMS" "false" Option "CustomEDID" "DFP:/etc/X11/edids/dell_32edid.bin" EndSection

Section "Monitor" Identifier "Monitor1" Option "DPMS" "false" Option "CustomEDID" "DFP:/etc/X11/edids/extron4k_edid.bin" EndSection

Section "ServerFlags" Option "StandbyTime" "0" Option "SuspendTime" "0" Option "OffTime" "0" Option "BlankTime" "0" EndSection

Section "Device" Identifier "Device0" Driver "nvidia" VendorName "NVIDIA Corporation" BoardName "Quadro RTX 8000" BusID "PCI:33:0:0"

#Option "DamageEvents"  "True"
Option         "UseEDID" "true"
Option         "ConnectedMonitor"   "DFP-0, DFP-1"
Option         "metamodes" "DFP-0: 3840x1440 +0+0, DFP-1: 3840x1440 +2560+0"

EndSection

Section "Screen" Identifier "metaScreen" Device "Device0" Monitor "Monitor0" DefaultDepth 24 SubSection "Display" Modes "3840x2160" EndSubSection EndSection `

This systems is one of about 200 we have in this environment and they are connected by 2 monitors, sometimes 4. This is the only system we are connecting remotely with vnc as a monitor system. We are unable to test on other systems due to the nature of our business.

Please let me know if you need more information and I will provide it.

Thanks!

TigerVNC / tigervnc

Display is not refreshed unless mouse movement over time #1838