LabView 2009 WebServer hangups

[kolan]

Hi all!

Here is a simple VI containing no controls, functions or libraries in LabView 2009 f3.

WebServer settings are default. After Tools->Web Publishing Tool operation from other PC we are connecting to this panel (IE6 for example) and putting a finger to F5-button not raising it.

Web page with the VI is refreshing continiously.

There are 3 results.

1. In DevEnv: LabView die.

2. In DevEnv: Need to restart LabView so WebServer reloads and connection restores.

3. In App.exe: die

4. In App.exe: LabView interpreter loose some while-cycles in case they exist but connection stored.

5. In App.exe: connection lost but the application working good.

Is it normal? Is there any WebServer settings to avoid this situation.

Message Edited by kolan on 02-03-2010 03:24 AM

[BCho]

Hey kolan,

Is there a reason why your are holding down F5 in your internet browser to try to continuously refresh the page. I am not sure I can think of a used case for doing something like this. Even if you were trying to monitor a VI continuously, it would take time to reload the page and even if everything worked as expected, you wouldn't be able to see your front panel because it would be in a continual state of refreshing. In regards to the outcome of this test, when you say the "DevEnv" are you referring to the development machine running the VI and when you say App.exe are you referring to the instance of internet explorer trying to view the front panel? 

If you are looking to view your VI as it is running, you should use the  'Embedded' Video mode. This allows you to view the front panel as it updates so there would be no need to refresh the browser. 

Message Edited by BCho on 02-04-2010 10:32 AM

[kolan]

Good evening BCho!

Pressing F5 is just an action which shows a way to achive LabView crash state.

Another way is closing Web-browser on client's PC when it connected to LabView's server.

App.exe - is an executable VI made by an action: Tools->Create an executable

VI may not be downloaded when I press F5 again. 

This methods shows that LabView crashes when improper client's request sent.

Does the NI-website die when you close Your browser ? 

(DE=DevEnv=Development Environment, App.exe - higher)

No, there are no reasons to do something what wouldn't help to find a solution.

Message Edited by kolan on 02-04-2010 02:08 PM

[Dennis_Knutson]

I've run those different scenarios and I have not been able to reproduce any of the problems.

[kolan]

The result appear not every time.

For a simple panel with no controls it can be reproduced on 20-40 webpage refresh or disconnect from remote panel.

For a panel with 2 buttons, one XY-chart, 2 tab controls and 2 multilists it can appear immediately or on 5-10 reconnect time.

There is a probability which is proportional network speed and number of controls.

LabView does not handle incorrect request and die/hangups/lost connection or begin to behave unexpectedly.

[kolan]

Just look at this example (in attach) which reproduces one of the problems... And sorry for my bad english, I hope You understand me...
Now we have to deliver the software to a customer (and register LV9) but this BUG...

F5continious video

[kolan]

There are bugs in LabView WebServer EVENTS and PROPERTY code. Not in the LabView engine!!!

LabView developers need to include checkups between WebServer and LabView engine for improper data sending and to reject all unknown data.

[kolan]

But if it is too hard to add such checkups into web-server because it may doesn't know anything about send/received data the second way is to realize verifications in the ThEvent.cpp and ThProperty.cpp LabView source code files. But the second way is a bad idea because the error and it's checking must be in one place.

I expect for Developer's reply 

[kolan]

not ThProperty.cpp but prop.cpp...

Message Edited by kolan on 02-08-2010 07:54 AM

[The_Chancenator]

Hi Kolan,

I'm still not sure why you would want to continuously refresh the page by pressing F5 repeatedly.  Do you see any issues when you are running the VI in "embedded" mode?