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Incredibly high CPU utilization

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Ripcord
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Incredibly high CPU utilization

Post by Ripcord »

Hi,

I just installed RC18 and am using UltraVNC for the first time (I've been using RealVNC on Windows).

I'm connecting to a non-UltraVNC server (in this case, Mac OS X). It displays okay as long as I don't select the "Auto" connection setting (otherwise I get some garbage at the top of the screen and no screen drawing), but I'm having a major problem with the client.

Regardless of the connection settings I specify, the client seems to be having some major performance problems. If I start doing anything on the remote system that requires ANY screen updates at all, the client gets EXTREMELY slow, CPU utilization goes to 100%, and the application becomes unresponsive until the (painfully slow) screen update is done.

I did some research on the site but haven't found anyone else having similar problems. Is it just me?

I'm running the client on XP SP1 on a 1.6ghz Pentium M.
Polet
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Post by Polet »

Did you install Video Hook Driver as well?
Per Aspera Ad Astra
Ripcord
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Post by Ripcord »

You mean the mirror driver?

When I tried to run the driver setup utility on the OS X system it just laughed at me...

I'd really like to use UltraVNC tho, it has features much superior to other VNC viewers, but uses REALLY high CPU/much slower updates compared to any others I've used with similar settings.

The problem where CPU would go to 100% and I'd get maybe 1 frame every 5 seconds is gone (I never saw this happen on any other machines so I have to assume it was something about the system I was using, or software conflict that no longer exists, though I haven't really changed anything...), so it's usable again, but still would be MUCH better if it was faster (now maybe 1-2fps on a no-packet-loss, nearly-zero latency 100mbps LAN).
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Rudi De Vos
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Post by Rudi De Vos »

-Server or viewer cpu 100%
-What compression does the viewer support.
-Try to play with the polling settings

In case it is the viewer that have a very high cpu. It is possible caused by the high refresh rate ultravnc is capable off.
There is not a lot you can do, then finding someone who can
benchmark the viewer at function level.

In case the server is 100%, install the driver, this should give about a 10% cpu use.
NightRyder
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Post by NightRyder »

Does it happen with lower settings? ie. higher compression.
The mac probably wont take that driver.
"connecting to a non-UltraVNC server (in this case, Mac OS X)"
As in, not an ultravnc program on the server?
Or, just a Mac running ultravnc?

If the first, what is the program?
Does ultravnc's server program run on a Mac?
using latest code.... always... except when im not.
Ripcord
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Post by Ripcord »

Since the threads in the "bug reports" section all appear to have been deleted for the 1.0 forum, reposting in this similar thread.

Key points:

- Viewer CPU goes to 100% on any screen update activity
- Server is Apple Remote Desktop VNC Server that ships with all Macs
- Problem only happens if connecting with at least high-color settings. Connecting with 256 color causes the viewer to explode (draws garbage at top of new window with correct geometry, then exits after approx. 1 second)
- I'd love it if I could install the UltraVNC driver on the server as per Rudi's suggestion. I assume we would need some Mac developers or to donate some hardware to Rudi before this could happen.
- Other VNC clients (RealVNC, TightVNC, etc) do not appear to experience this problem.
Ripcord
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Post by Ripcord »

Any interest in working on this? It's still a problem with the latest release. I can provide network traces, etc if that will help...
redge
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Post by redge »

I read of your first post, you installed RC18,
so now there a UltraVNC 1.0.1 (aug 6 2005)
Did you try it ?
UltraVNC 1.0.9.6.1 (built 20110518)
OS Win: xp home + vista business + 7 home
only experienced user, not developer
Ripcord
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Post by Ripcord »

1.0.1 has the same problems.
wwiii
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Post by wwiii »

There is no ultraVNC for Mac OS X but there are compatible freeware products you can use to connect to ultraVNC.

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Wheat Williams
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