Queue reference genesis location

[dchip]

Background: 
I am running multiple vis simultaneously.  Each vi contains several queue references which are written and/or read. 
I created a debugging vi to monitor the # of elements in all of my queues.
 
Question:
Is there any way to indicate which vi obtained the first reference to a particular queue (i.e. what vi generated the initial reference).  Along the same lines is there any way to programmatically determine which vis are using particular queues?   Any thoughts?
 
Thank you,
 
-David

[srikrishnaNF]

hi dchip,

   Ofcourse you can know which VI is using which queue by knowing the queue reference number.Always if you create a queue automatically you can type cast the queue reference to a U32 value.That value will give the queue value.

Thanks and regards,

srikrishnaNF

[tst]

NI has a product called the desktop execution trace toolkit which can show you the various resources your VIs use and it probably includes that information.

Another option is to add a wrapper to the obtain primitive, so that every time you call it, it logs the caller (using the Call Chain primitive).

I wouldn't use the other method suggested, simply because it's not guaranteed to work - the 32 bit representation of the reference is an internal thing, so you can't rely on it to always increase.

[F._Schubert]

The Obtain Queue function has an output called: Created New? which will is true the first time it's obtained.

Felix

[DFGray]

The Desktop Execution Trace Toolkit is probably the way to go to get the information you want.  It will give you a list of which VI calls what queue in what order.  It also shows which VI acquires what queue in what order.  The toolkit is available starting at LabVIEW 8.6 (earlier versions did not include the needed hooks in the LabVIEW code).

An alternate method is to add hooks to your code which will post timing information to another process.  In Windows, you can do this by writing to the debug output using the Windows system DLLs.  This method is described here. There are also replies which should give enough info to do this for Linux and Mac OS X users.

[Corny]

when a VI creates the queue, why not create an unique queu name that not only holds the name of the queue but also the VI name that has created the queue (or any other static information you might need). If another VI reads this queue, and suddently needs to know who initiallt created the queue, you can get out the Queue name by using the "get queue status VI" on the queue reference?

[Ben]

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dchip wrote:

Background: 
I am running multiple vis simultaneously.  Each vi contains several queue references which are written and/or read. 
I created a debugging vi to monitor the # of elements in all of my queues.
....

Thank you,
 
-David

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How are you getting the refs to the queues?

How are you handling different queue types?

Are after the call chain that created the queue or the exact VI with the create primative in it?

Ben

[tst]

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Corny wrote:
why not create an unique queu name...

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Because then you need to know who created the queue in order to know the queue name so you can obtain a reference. Kind of circular.
Either that, or you would need to transfer the reference around using some sort of global, which is a bad idea.

And if you move the creation into a subVI, you're basically back to my original suggestion of a wrapper.