UltraVNC server settings & performance impact

[VncUser2014]

Hello, we are a big user of UltraVNC server/client (+ 500 installations).
We are using UltraVNC in a mixed OS environment of Windows XP, Windows 2003R2 Server, Windows 2008R2 Server, Windows 2012R2 Server.

As we have seen several problems regarding screen updates & ultravnc host performance during sessions, I have a few questions:

1. What is the correct server installation method for the latest version of VNC on a Windows platform? Always install the setup + addons package?

2. What is the difference between the mirror driver & the hook in the addons? Do you need both options installed at all times?
Are these options OS-dependant? I mean, do you need different addons on different Windows versions? (XP to 2012R2 / ?

3. Is the latest stable release ok to install & use on older Windows operating systems like XP / 2003Server? Or is an older version recommended?

4. What are the optimal settings for server screen update handling? Between branches you see our current default settings for Win 2003R2.
The impact of these settings seem to have a big influence both on the accuracy of the screen handlding, and especially on the load on the host server system.

Poll Full screen (ultra fast) [true]
Poll Foreground Window [true]
Poll Window Under Cursor [true]
Poll Console Windows Only [false]
Poll On Event Only [false]
System HookDll [true]
Video Hook Driver [false]
Low Accuracy (Turbo Speed) [true]
Max CPU [40]

5. Several of our hosts are time critical servers, and during vnc session, related to the settings above, we can clearly see an impact on the server load (not CPU wise) but still the system gets slower.
I wonder if this has to do with the issue described by another forum user here : https://forum.ultravnc.net/viewtopic.php?f=54&t=30956

6. Is there a possibility to close down idle VNC sessions automatically? At some of our systems, multiple VNC sessions are opened to the same server for a very long time because people do not close the connection.
I know there is a timebased automatic closing option that can be configured, but it would be better if the time was not session time, but idle session time. Is this possible?


Thank you for any input & feedback.

[Rudi De Vos]

4. We usual use this
Poll Full screen (ultra fast) [true]
Poll Foreground Window [false]
Poll Window Under Cursor [false]
Poll Console Windows Only [false]
Poll On Event Only [false]
System HookDll [true]
Video Hook Driver [false]
Low Accuracy (Turbo Speed) [true]
Max CPU [40]

Are you able to test 5.
Forgot this post and it's a simple change
Version with SDTimer removed
http://www.uvnc.eu/download/1204/winvnc_SDtimer.zip

[VncUser2014]

Which version do I need to use to test this WinVNC.exe without SDTimer?

[Rudi De Vos]

without SDtimer to see if you can see any performance improvement.
Possible https://forum.ultravnc.net/viewtopic.php?f=54&t=30956 has only impact on specific systems.

[VncUser2014]

What I meant was, which installer version to start from? I guessed 1.2.0.3, stopped the service, replaced WinVNC.exe and started the service again.
I tested this on two systems, would like to test more when I have the opportunity.

Is this special WinVNC.exe without SDTimer only for 32bit version or also for 64bit? I can test it on a Win2008R2 x64 systems as well.

Also, I notice that using both hook & mirror driver at the same time gives best results on Win2003 systems? Maybe the hook driver is not installed there? Is there a way to check this?

Thanks

[Rudi De Vos]

Just replace winvnc.exe, and in case it's a service stop replace start.
Test Version is X86 for xp ( windows 2003) and higher

[VncUser2014]

So far, this version without SD timer is running stable on the Windows 2003 x86 server systems.
Do you plan to add this change as standard in the next UltraVNC releases?

[Rudi De Vos]

yes, i'm current compiling the November update.
Update =1.2.0.4 online via forum + extra changes
- SDtimer replaced
-a better uvnc_settings.exe with more options and proper defaults when used to create a new ini file.

[VncUser2014]

Looking forward to the new version then, thanks for the feedback.
Having the opportunity to configure an idle connection timeout is not considered? (I mean sessions that are idle are closed by the server after x minutes)

[Rudi De Vos]

Person A want the session to stay open, even when viewer is minimized.
Person B want the session to be closed on idle

The problem is that we need to generate data to keep the ports ( on the router open, else they close after X time and viewer/server disconnect).

You can try using uvnc_settings.exe or manual in the ini file
keepalive interval 5000=83min ( Then no keepalive is transmitted, default is 5 sec)
idle timeout = 600 ( without keepalives, you should reach an idle counter and connection breaks
socket timeout = 300

1.2.0.4 has been placed online via uvnc.com

[VncUser2014]

I understand, you cannot satisfy everybody and still UltraVNC is a free product
I was thinking in the terms of an optional switch inside the server configuration: if the vnc server receives no keyboard or mouse input for X minutes, the server stops the connection for that given session.
If this value is set to 0 inside the vnc config, then connections are never ended after being idle. That would satisfy everybody's wishes.

Something like that. But I think you mean with "The problem is that we need to generate data to keep the ports", that you are simulating keyboard or mouse input to keep the connections alive?

Thanks for the information & support!

[Rudi De Vos]

There is already an idle detection, but it works on all data.
The idle detection was broken when we added the keepalive message
WIthout the keepalive, the idle detection should work...

An extra timer need to be added, that only use the input or we can replace the current idle timer ( he as no use with keepalive on) so he is only
impacted by a "input messg "....
I see what we can do for next ( Decemeber) update

[VncUser2014]

That would be great, I guess this would help a lot in a factory environment where multiple HMI's can have open VNC sessions to a central server.

[Rudi De Vos]

It actual need to be a viewer option, the server only know if all input, all viewers need to be idle before server input is idle.
The viewer know his own input.

The we better add a slow mode to
viewer idle->viewer close
viewer idle->ask updates very 10 seconds, go in slow mode

[VncUser2014]

Hmmmm... I guess it would make more sense to do this from the server side (VNC server handles each session seperate doesn't it?)
It would make sense that the server admin decides if sessions get closed automatically after x idle time. If you put this feature in the viewer, it's the end user that decides it. It's also on the server side that you decide to keep existing connections, only allow one connection at a time, etc...

[Rudi De Vos]

It's complexer then that.

If a idle timeout close the server session, the viewer sees a close session.
Default desktop/logon desktop use other sessions, to be able to coop with session switches the viewer
auto reconnect on session close, because he think the server switched session.
Closing a server session wil cause a viewer reconnect !

To be able to set the options on the server site, you need to send the option parameters to the viewer.
But it is the viewer that does the disconnect on idle inpu.

[VncUser2014]

OK thank you for the detailed information, I understand now.

[Rudi De Vos]

Please test 1.2.0.5 ( forum)
idle disconnect was added