From: Paolo Abeni <pab...@redhat.com> Date: Wed, 24 Jan 2018 15:54:05 +0100
> Niklas suggested a possible relation with CONFIG_IRQ_TIME_ACCOUNTING=y > and indeed he was right. > > The patched kernel under test had CONFIG_IRQ_TIME_ACCOUNTING set, and > very little CPU time was accounted to the kworker: > > [2125 is the relevant kworker's pid] > grep sum_exec_runtime /proc/2125/sched; sleep 10; grep sum_exec_runtime > /proc/2125/sched > se.sum_exec_runtime : 13408.239286 > se.sum_exec_runtime : 13456.907197 > > despite such process was processing a lot of packets and basically > burning a CPU. So IRQ_TIME_ACCOUNTING makes the scheduler think that the worker threads are using nearly no task time at all. The existing ksoftirqd code should hit the same problem, right?
