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BUG: Old Version Viewer will crash Server 1.0.9.6

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YY
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BUG: Old Version Viewer will crash Server 1.0.9.6

Post by YY »

I found one serious issue, which I think should be fixed first.

The new issue I discovered is:

If this UVNC server is connected from a old viewer (1.0.8.2 in my test), the server will crash !!!
One of the winvnc.exe session will cause 100% CPU comsumption (in my dual core system, one core is fulled occupied).

I then did the same test on 10961 beta, 1.0.9.6 & 1.0.9.5 servers, the result (all run on WinXP Prof):

10961 beta & 1.0.9.6 -- same result, UVNC server consume 100% CPU

1.0.9.5 -- viewer terminated after a few moment automatically, and the server EYE icon changed to yellow for a few seconds, then resumed to Green color. Connection was not establish, but the winvnc.exe not crash, nor used 100% CPU.


I think this must be fixed first. In real application, an old viewer connection will crash the server is totally not acceptable.
Last edited by YY on 2011-04-17 09:54, edited 1 time in total.
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Rudi De Vos
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Re: BUG: Old Version Viewer will crash Server 1.0.9.6

Post by Rudi De Vos »

YY,

On my system, viewer 1082 connect to 1096 server without disconnect and cpu 100%.
This mean at only happen with a specific option.

What are the viewer options ?
How do you test it ?
YY
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Re: BUG: Old Version Viewer will crash Server 1.0.9.6

Post by YY »

OK! After hours of testing & testing, again & again, finally I locate the setting the causing this issue: the Remote Cursor Setting of viewer.

Here are my test results of 1.0.8.2 viewer connecting to 10961 server, with following setting:
- Track remote cursor locally -- server 100% CPU
- Let remote server deal with mouse cursor -- Connection established properly, CPU consumption normal. :-D
- Don't show remote cursor -- server 100% CPU

On the other hand, when using the 1.0.9.5 or 1.0.9.6 or 10961 viewer to connect to 10961 server, all are working properly with any one of the settings.



====================================================

Although (probably) the problem source is located, I would like to report some interesting phenomenon I saw during my test.

In following, the 10961 server was configured to accept multi viewers coonection (i.e.: Keep Existing Connections), the viewer is 1.0.8.2 and 1.0.9.6

1. If the 1.0.8.2 is the first viewer connected, the server will jump to 100% CPU.

2. If a 1.0.9.6 first connected, and then followed with 1.0.8.2, this will NOT cause the 100% CPU. Even then the 1.0.9.6 quitted and left the 1.0.8.2 alone, the server still running properly.

3. If the 1.0.8.2 is the first viewer connected, the server will become 100% CPU, but the server is NOT crash. At this moment, if a 1.0.9.6 connected, it will cause the server to recover -- the CPU consumption return normal.

Hope these information can help.
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Rudi De Vos
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Re: BUG: Old Version Viewer will crash Server 1.0.9.6

Post by Rudi De Vos »

First test was normal, then testing from a Vista (viewer) and after
erasing the default settings i was able to repeat it.

Still need to trace the cause...
Found, loop
updated 10961 bins
Last edited by Rudi De Vos on 2011-04-18 20:53, edited 1 time in total.
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