On Monday, September 12, 2016 06:14:44 PM Peter Zijlstra wrote: > On Mon, Sep 12, 2016 at 12:01:58PM -0400, Chris Metcalf wrote: > > On 9/7/2016 5:11 PM, Francis Giraldeau wrote: > > >When running only the test_jitter(), the isolation mode is lost: > > > > > > [ 6741.566048] isolation/9515: task_isolation mode lost due to > > > irq_work > > > > > >With ftrace (events/workqueue/workqueue_execute_start), I get a bit more > > >info: > > > > > > kworker/1:1-676 [001] .... 6610.097128: workqueue_execute_start: > > > work struct ffff8801a784ca20: function dbs_work_handler > > > > > >The governor was ondemand, so I tried to set the frequency scaling > > >governor to performance, but that does not solve the issue. Is there > > >a way to suppress this irq_work? Should we run the isolated task with > > >high real-time priority, such that it never get preempted? > > > > On the tile platform we don't have the frequency scaling stuff to contend > > with, so > > I don't know much about it. I'd be very curious to know what you can > > figure out > > on this front. > > Rafael, I'm thinking the performance governor should be able to run > without sending IPIs. Is there anything we can quickly do about that?
The performance governor doesn't do any IPIs. At this point I'm not sure what's going on. Thanks, Rafael
