question about a function attribute

Hi, every one.

I have a question on a attribute of function module.

There is a attribute named 'Global'. We can find it in the function builder->attributes tab->General Data.

It's a checkbox and we can set it by menu Edit->interface->Globalize parameter.

SAP help says 'If you select this field, the system declares the interface parameters in the function group globally. '.

My question is when two function which in an function group are called in the same time, these Globalize parameter will impact each other or not? Assume they have the same parameter name.

If using this Globalize parameter, is there any synchronous problem?

Hope the reply of you. Thank you.