Shared Variable and classes

Hi friends,
1.can you tell me the Disadvantages of Shared Variables?
2.What is classes ,how to make it?
Raj

Hi! Raj
Shared Variables
shared variables share data between loops on a single diagram or between VIs across the network. For doing that they break the LabVIEW dataflow paradigm.
Disadvantages:
1. Using variables allows for race conditions and incurs more overhead than passing the data by wire(break the LabVIEW dataflow paradigm).
Race conditions happen when you, for example, write data to a shared resource from multiple operations faster than you read data from the same shared resource.
2.You must have a project open to create a shared variable
You can also read more about shared variables at http://zone.ni.com/devzone/cda/tut/p/id/4679
Attachments:
Race condition.PNG ‏57 KB

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