Re: [PATCH 00/18] tracing/ring-buffer: fixes for latency tracer [2.6.32]

[Jan Blunck]

On Mon, Sep 07, Frederic Weisbecker wrote:

> On Mon, Sep 07, 2009 at 12:20:50PM +0200, Jan Blunck wrote:
> > On Sat, Sep 5, 2009 at 5:06 PM, Arnaldo Carvalho de Melo<acme@xxxxxxxxxx> wrote:
> > >
> > > I did a quick port to tip/rt/head and couldn't reproduce the problems I
> > > was experiencing, thanks!
> > >
> > > I've put the ported patch series at:
> > >
> > > http://userweb.kernel.org/~acme/rostedt-rb-rt
> > >
> > 
> > Nice, this also seems to fix my problem with the hanging wakup
> > selftest. At least the system continues to boot. However, I still get
> > this:
> > 
> > [   13.739115] Testing tracer sched_switch: PASSED
> > [   14.002071] Testing tracer function: PASSED
> > [   14.158816] Testing dynamic ftrace: PASSED
> > [   14.512524] Testing tracer irqsoff: PASSED
> > [   14.693519] Testing tracer preemptoff: PASSED
> > [   14.853519] Testing tracer preemptirqsoff: PASSED
> > [   15.013506] Testing tracer wakeup:
> > [   15.134004] hrtimer: interrupt too slow, forcing clock min delta to
> > 27508383 ns
> 
> 
> 
> Ah, Ulrich Lukas also reported me such warnings. I would like to
> track the reason of these messages (the hrtimer hanging detection
> seems to warn too early).
> 
> Could you please send me your config, I hope I could reproduce it.
> 

I only see that on one of my systems, a 32 core Opteron and not on my 8
core. So it seems that size does matter ...

Attachment: hrtimer-slow.config
Description: application/config