madskg

Thanks for your inputs. I will give UDP a go. Maybe Active-X is the way to go, i've never used Active-x myself, so that can be plan b. I don't know how the C# program is made, but i suppose that the C# program maybe can keep the DLL in memory, and the shared variables would remain connected (and saving the reference in a functional global)...

I'm using a Labview Shared Library (DLL) to comunicate between a C# program (made by another company) and a labview Executeable (which means different processes) on the same PC. Currently i'm using network published shared variables, to communicate between the Labview DLL and the LABVIEW program (both made by me) which works well, except for the performance. Each time the DLL is called it needs to connect to the shared variable, which takes between 50 and 300 ms. When it is connected, the data transfer is instant. I have tried to use the PSP "Open Variable Connection In Background", which is a bit faster, because it doesn't wait to verify the connection. But it still adds some overhead. I have also tried to use notifiers from this example: https://lavag.org/topic/10408-communication-between-projects/ . Opening connection and sending the notifier takes 50 - 100 ms. I guess both the notifier and the shared variables are "slow" because they use the network communication, even if it is the same pc both programs are running on (localhost). Does any of you know of a faster method of communicating between a program that is running continuesly (connection open constantly) and one only exectuted when new data is ready (connection "re"-opened on every instance)? Thanks in advance. Best Regards Mads