Re: High latency of a system based on 5.19 rt

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Tue, 2023-09-26 at 12:30 +0000, Clark Williams wrote:
> On Tue, Sep 26, 2023 at 7:05 AM Mike Galbraith <efault@xxxxxx> wrote:
> > On Mon, 2023-09-25 at 18:30 +0200, g.medini@xxxxxxxxxxx wrote:
> > > # tracer: wakeup_rt
> > > #
> > > # wakeup_rt latency trace v1.1.5 on 5.19.0-rt10
> > > # --------------------------------------------------------------------
> > > # latency: 357 us, #401/401, CPU#0 | (M:preempt_rt VP:0, KP:0, SP:0 HP:0 #P:2)
> > > #    -----------------
> > > #    | task: ktimers/0-15 (uid:0 nice:0 policy:1 rt_prio:1)
> > > #    -----------------
> >
> > The first thing that pokes me in the eye is that priority. I'd bump
> > that a lot.  As it sits, anything high priority ktimers may wake when
> > it finally gets the CPU gets to enjoy all the latency ktimers is eating
> > in this trace due to it having been deemed relatively unimportant.
>
> Hmmm, IRQs are running at FIFO:50 by default. Do we want the ktimer
> running above the IRQ service thread? 

I think so yeah, quick like bunny wakeup resource should punch through.

	-Mike





[Index of Archives]     [RT Stable]     [Kernel Newbies]     [IDE]     [Security]     [Git]     [Netfilter]     [Bugtraq]     [Yosemite]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Linux ATA RAID]     [Samba]     [Video 4 Linux]     [Device Mapper]

  Powered by Linux