UI Thread Setting of Preferred Execution System

Updated Nov 3, 2023

Reported In


  • LabVIEW

Issue Details

What does the UI Thread setting mean for Preferred Execution System in VI settings?


The user interface thread (UI thread) is a thread allocated by LabVIEW for user events (e.g. keyboard/mouse input). This thread can also be used for other purposes, like executing VIs with property nodes or for executing thread-unsafe CINs and DLLs.

Additional Information

A thread-unsafe DLL can be set to run on the UI thread from the settings of a Call Library Fn Node.

You can read more about the various execution systems in Multitasking in LabVIEW .

Even if you use the standard execution system, the user interface is still separated into its own thread. Any activities conducted in the user interface, such as drawing on the front panel, responding to mouse clicks, and so on, take place without interfering with the execution time of the block diagram code. Likewise, executing a long computational routine does not prevent the user interface from responding to mouse clicks or keyboard data entry.