Changing Time stamps from Monotonic to Real-Time
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Hello,
This is probably more of a question that is probably designed to make everything on the voxl2 stop working correctly but I am going to ask it anyways.
What would happen if we changed the code to use the real-time clock instead of Monotonic for voxl-camera-server and the voxl-imu-server?
Would the other services not function correctly? Would they have to also be changed to Real-time clocks? Is everything going to work smoothly like before?
Not sure where IMU-server is located, otherwise I would try it out and post here but I see Camera server can access real-time but it is not used.
Thank you for your time,
Aaron Porter -
@Aaron-Porter Why would you want to do that?
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A second device use NTP + PPS for time sync. the problem is that the second device uses the Real-Time clock when time stamping its data. The goal is to sync up the data from the second device with the camera-server, and IMU data generated but the VOXL2. The Problem is that camera-server and imu-server use Monotonic. There is an obvious offset between real-time and monotonic but that varies from the offset +/- 150 ms. This wouldn't be a huge deal but using that data with that level of deviation cause problems with the postprocessing.
So the current thought is if it is possible to just use the real-time instead of monotonic then there will still be an offset but should be far more consistent especially when using Pulse-per-second (PPS).
Thank you,
Aaron Porter -
@Aaron-Porter Using CLOCK_REALTIME can be bad because it can move around. That can lead to errors when the clock jumps and it makes it seem like a deadline has passed that hasn't, etc. So, it would be much better if the application using CLOCK_REALTIME switches to CLOCK_MONOTONIC instead.
