On 2020-10-27 11:34:11 [+0100], Daniel Wagner wrote: > On Tue, Oct 27, 2020 at 11:28:51AM +0100, Sebastian Andrzej Siewior wrote: > > Is it running as a RT task? > > root@c2d:~/rt-tests# ./pi_stress > Starting PI Stress Test > Number of thread groups: 1 > Duration of test run: infinite > Number of inversions per group: unlimited > Admin thread SCHED_FIFO priority 4 > 1 groups of 3 threads will be created > High thread SCHED_FIFO priority 3 > Med thread SCHED_FIFO priority 2 > Low thread SCHED_FIFO priority 1 > > It says so, let me double check if those task really run with SCHED_FIFO. urgh. You wrote pi_stress and I read stress-ng. Okay this explains it. > > Otherwise it looks that if you throw enough non-RT load on the system, > > RCU can not catch up which does not sound good. > > I think this is what Clark tried to tell me. If I understood him > correctly the test tool is not correct though. a dummy RCU section might help. But otherwise it is correct :/ Sebastian
