Very high CPU usage on a DUAL 3.2GHz?

[Markos23]

Hi, i never had this problem on all the machines i installed UVNC 1.0.1, but i just installed a UVNC Server on a HP DL380 DUAL 3.2Ghz processor with windows 2003 standard installed and 2 ethernet controllers.

When VNC is in idle mode, no problems registered.

When a client connects to this Server, i see that the CPU usage on the Server goes to 40-50%, causing the server to slow down all the operations, and making it unusable.

I see the process prority is set to normal, as always.

I tried both in service mode and not, and still i have the same problem.

I repeat, it never happened on the other machines where i installed UVNC. And this is a fresh Windows 2003 install, directly installed from HP people.

Any suggestion?

[vertexwahn]

did you install the ultra vnc mirror driver?

[Guest]

no, should i?

but i found some topic speaking about 24 bit depth problems, i'll try to see if the video mode is set to 24 as soon as i'll have access again to the server.

[Guest]

i forgot, i never installed the mirror driver on my other servers, but i only had 8/9% cpu usage maximum, on machines that are very very lesser performant than this one.

[Guest]

I had the same problem... high cpu (using 95%) when I logged on using vnc but normal otherwise.

I corrected the problem by removing the hardware acceleration on the video card.

[bevtech]

yes there seems to be a slight problem with the newest mirror driver and hardware acceleration. I had a ghosting effect until I turned mine off. This seems to be really noticable in window 2003 servers.

[Guest]

I had the same problem... high cpu (using 95%) when I logged on using vnc but normal otherwise.

I corrected the problem by removing the hardware acceleration on the video card.

This worked for me as well. Thanks!

[JonnyPhenomenon]

I had the same problem... high cpu (using 95%) when I logged on using vnc but normal otherwise.

I corrected the problem by removing the hardware acceleration on the video card.

This worked for me as well. Thanks!

Oh man, you have no idea how glad I am to have found this. I had one seerver out of about 10 that was completely trounced by attached vnc clients. 100% cpu for winvnc.exe on our NAS box. I thought it was something to do with the NAS version of windows 2003. but as it turns out, it was the video acceleration bit! Now I am going frmo machine to machine in the server room, with the task manager open so I can watch the cpu % that winvnc.exe is using, I change the video acceleration to none, and POOF, 8-9%. THANKS A BUNCH!

[Guest]

Just another vote - Disabling hardware acceleration worked for me aswell. Reducing the CPU from 80%~90% down to 3%~40% (yes three percent!).

[scottcopus]

I have two Windows Server 2003 machines. Only one of them had that high CPU utilization problem... until I moved the hardware acceleration all the way off as suggested above. I still don't understand why this worked for this ONE server... because both of these servers had the acceleration on that "2nd" notch ("disable all but basic accelerations") to begin with. The other server still has this basic accelerations enabled... and it has never had CPU utilization problems with VNC.

Here's the specs on the server that had high CPU utilization to begin with... that I had to completely disable video hardware acceleration:
Dell PowerEdge 2650
Single Xeon (with hyperthreading) CPU
2GB RAM
VIDEO: RAGE XL PCI Family (Microsoft Corporation) v5.10.2600.6013 3/24/2005

Here's the specs on the server that had no problems... that was already defaulted on the "2nd notch" hardware acceleration:
Dell PowerEdge 2850
Dual Xeon (with hyperthreading) CPUs
1GB RAM
VIDEO: RADEON 7000 SERIES v6.14.0010.6422 1/21/2004

So does anyone have any idea what the REAL source of high CPU utilization is... at least for Windows Server 2003 systems?

P.S. I uninstalled UltraVNC and also tried TightVNC. TightVNC had the same high CPU utilization problem too.

Scott.