Brief description of the setup: We have a mobile platform, where the OEM ECU and different sensors are connected to a X90 PLC. These sensor data and setpoints are exchanged via Powerlink to an APC910. There, a hypervisor system with an AR and a debian GPOS is installed, exchanging data via exOS. We…

Ok, well. we ruled that out then. Your latency doesnt look alarming. what you show there are acceptable results, mostly as a result on being second-in-line on a hypervisor system - AR will always have priority over the GPOS system, so the 10-50us you see in standalone runs are not always acheivable…

Hi, I haven’t any experience with ExOS or deeper knowledge of Hypervisor system. But at least, the data I see looks a bit similar to an issue I had many years ago (using ArWin, not Hypervisor). That’s the reason why I want to share my thoughts: the data im the backtrace points in the direction o…

I do have quite a lot of experience with exOS :smiley: but I would need some more information. Its been a while, but it seems you’re using the ethernet based communication? → lxi_eth_client_process If so, that implementation is not deterministic and was only designed for simulation purposes, ie. u…

Thanks a lot for your insights and comments. Hi Patric, you helped us a lot in the beginning to setup the project :slight_smile: It worked well for some years, but these errors are getting more and more. Might be related to an increase in network traffic as already mentioned. The lower task class…

Humm, yep that certainly looks like shared memory! I think youre good in that respect. maybe the semtake etc comes from the locking of resources between the ExApi function blocks and the rest of the data commincation. in order to have consistent data there are a few semaphores/critical section betwe…

The DMR lives in TC#5 as can be seen in the screenshot above, as well as the exOS application does. The hottest candidate for me is still something blocking the hardware bus for the system tick exception, which might be solved by increasing the system tick and refactoring the task classes. But if t…

Ok did you disable the storageMon? If not please do so. [image]

Yep. This could actually be a thing, as we found issues with the storage monitor influencing the behavior of the Linux realtime behavior on the 4.91 versions (it was introduced before but thats where we really came across it). The feature is in a later version, huess 4.92 but it could also be 4.93. …

HI @Christoph_Frohlich what is status of this discussion, have you found solution? can you update us?

Not yet. I was able to somehow reproduce at least the “failed system tick” exception: I use a ROS stack on the GPOS linux side. Sending ROS actions periodically in a loop triggers the exception. Don’t ask me what the underlying DDS communication layer is doing on the network card to influence the t…

SERV Mode after exceptions on Hypervisor system

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Christoph_Frohlich (Christoph Fröhlich) March 18, 2026, 10:04am 8

I don’t see this option even in advanced parameter mode? The project is running on AR B4.91, if this is relevant here.

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SERV Mode after exceptions on Hypervisor system

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