Hi Gaute,

When you say that you are running Linux on core 0 and FreeRTOS on core 1, do you mean that you are running both Linux and FreeRTOS on the Cortex-A cluster in separate virtual machines, using a hypervisor?

Or are they running on separate clusters, such as FreeRTOS on Cortex-M/R and Linux on a Cortex-A?

Cheers,

Stefano

On Mon, 7 Sep 2020, Gaute Nilsson via Openamp-rp wrote:

We are running Linux on core 0 and FreeRTOS on core 1.

We have a high priority FreeRTOS task that needs to run with a 100 µs interval. When the system is up and running, no cross core communication takes place.

If I login with a ssh session into the Linux core, this will cause a performance hit on the FreeRTOS core and cause the high priority task to miss its deadline.

I can see that even an ISR on FreeRTOS core that normally takes 4.5 µs to execute, temporarily will take 7.6 µs to execute just when I open a ssh session into Linux core. So everything will temporarily run slower on FreeRTOS core before it goes back to normal.

What can cause this, and how can we prevent activity on Linux core affecting performance on FreeRTOS core?

-Gaute Nilsson