Increase pixHawk Frequency

I’m using pixHawk on VINS, and the frequency needs to be at least around 200Hz to make sure the program works properly. I used Qgroundcontrol to calibrate pixHawk. It seems no matter what airframe I chose, the publishing frequency remained at around 50Hz.
I read some online posts about modifying an extras.txt file but I don’t seem to have it. Does anyone know how to increase the frequency up to at least 200Hz?
Thanks much!