Simultaneous Execution of Object Methods

[DanielSchick]

Hej Matthias,

Just a simple question. It seems that one cannot execute two methods of the same G# object simulatneously.

Is that correct?

Cheers

Daniel

[Mattias_Ericsson]

Hi Daniel,

Let's see if I understand your question correctly. For an object executing methods in parallel you could have two situations:

1) The method you try to execute in parallel is one and the same. In order to get this to work, it needs to be set as reentrant, just like any VI. This is set from VI Properties->Execution->Reentrant "Share clones..." options. This situation also occurs for two different objects using the same method in parallel. This is the way LabVIEW works.

2) If there are two different methods you try to execute in parallel, this works just fine without making them reentrant.

However, if you are using the attributes in the methods using the "In Place Element" structure, only one of the methods could be executing inside the "In place element" structure, forcing the other method to wait until it is finished. Don't place any code inside the "In Place Element" structure that is not needed there and will keep  the attributes "locked" longer than necessary.

I guess the answer to your question would be: Yes, two methods could execute in parallel on the same G# object, but can't access the attributes (inside the "In Place Element" structure) at the same time.

Regards,

Mattias

[DanielSchick]

Alright, that was the problem. I am using the In Place Structure quite heavily, since I thought it speed up my application.

But I havnt thought about the blocked attributes.

Thanks a lot so far...

[Mattias_Ericsson]

Hi again,

Using the "In place element" structure directly in you code and set "return data"=FALSE on the GetAttribute, will actually improve your performance a lot, since you will avoid a lot of data copying by LabVIEW. You are absolutely correct there. Especially when you have many attributes carrying a lot of data like waveforms and arrays. Using the "in place element" structure directly in your code, instead of letting "GetAttributes" return data will be a hugh difference in performance, but sometimes it is quite nice to set "return data" = TRUE when you have e.g. a single simple attribute like a boolean or integer since the code will end up quite clean and it will hardly make any difference in performance.

Just don't put more code than you need inside the "In place element" structure, preferely no code at all, just get or set the data you need.

- Mattias