Best way to use variables seperately for each clone VI

[brucexliu]

I am writting an VI that could be open for multiple times, Each opened one is an instance VI(VI clone). Because it's complex so I have to use global variables or functional global. But comes with question, how can VI clone 1 and VI clone 2 use the different set of global? I mean each clone could manage its own global. For example, global A initialize to 1. VI clone 1 write global A to 2. so all subVIs called by clone 1 get global A as 2. But in clone 2 and all its subVIs the global A is still 1. The only way I figured out to do this is using call chain to find current clone name. And then search for the global of the clone. It works but may have performance issue in the future that each time I read or write global means a search operation and a get call chain operation. Is there any better way to do this?? Many thanks！

[brucexliu]

And also I think functional global is performance better than global when dealing with large set of data. Am I right?

[moderator1983]

Global variable has to be non-reentrant, you can probably make a global variable with an array of 'Data-type' that you were planning to have in Global 1 & 2 separately. Now each Clone has its own space (identified by the array index)...!!

But still at sub-VI level it should know, whether its caller is Clone-1 or Clone-2..., now apart from using 'Call Chain' you might want to pass the name of clone to each sub-VI, so that instead of using "Call Chain", the sub-VI already have the Clone ID available with them...!!

[brucexliu]

Well, it's ok if this is a project about hundred VIs. But there are thousands VIs so pass the clone name to all subVIs may not be an option.

Visit global by index, sure. But I mean is there any way to avoid calling "call chain"? 

[moderator1983 · Accepted solution]

For a sub-VI(s) to know, who is its caller, there is only two methods possible:

1. use 'Call Chain'.

2. Pass the name of Caller.

I cant think of any third method...!!

Now even if there are thousands of sub-VIs, do they all need the name/identity of caller..?? If thats the requirement... probably you should re-design the architecture (yeah I know it sounds painful)...!!

[Yamaeda]

Assuming you have your dataset/controls as a cluster (which you should), use that cluster as input and output of the VI. In the main VI, use an Array of Clusters. Feed each VI their data, collect result.

/Y

[brucexliu]

Thanks.

I prefer call chain then..