RT Computer typically will have
   Time Critical Loop(deterministic response)
   Non Critical loop (Monitoring info to and from the  Host Gui)

Recommendations(to reduce Jitter)
Minimize the use of interrupts(COM Port type cards are interrupt driven devices), Disable Dedugging tools on on RT LV vi,,Disable Com is not used.
Use FIFO for Time Critical and Host Comm loop communication.
Use Fix Size Array. NO build array type function in time critical or Host loop.

LV Shared Variable
Provides a means
to have access to
variable access the
network between the Host and the RT.
The LabVIEW project makes it easy to created the SharedVariables
(Minimize the number of SharedVarible  from and to the RT and Host to reduce Enet traffic)

Provide a way to verify Deterministic quality(jitter) at a minimum use the parameter from the TimeCritcal TimedLoop structure.

Related Software Development Tools
LabVIEW(r)
LabVIEW RealTime