[Xenomai] Low latency under stress, otherwise high latency
rpm at xenomai.org
Wed Feb 28 19:06:39 CET 2018
On 02/26/2018 10:34 PM, Julian Viereck wrote:
> Hi folks,
> after installing Xenomai 3.0.5/kernel 4.9.38 following  on our Dell
> Precision 5820 machine (Intel Xeon W-2145), there are high latencies
> when the system is at rest. When starting a stress test via `stress -v
> -c 8 -i 10 -d 8`, the latency goes down (see terminal output below).
> Usually I would assume the latency increases with higher load and not go
> down. Does someone has an idea where to start in debugging / fixing the
> high latencies? Note that the cores are in C0 state 100% of the time
> (with and without the load on the machine).
Maybe a SMI issue . You may want to boot your hardware with a vanilla
kernel (unpatched, no Xenomai), then run the hwlatdetect test from the
rt testsuite . If SMIs are detected, you may want to ask your BIOS
vendor to fix their code (some do actually).
More information about the Xenomai