lkml.org 
[lkml]   [2007]   [Dec]   [2]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [BUG] Strange 1-second pauses during Resume-from-RAM
On Sun, 2 December 2007 21:07:22 +0100, Ingo Molnar wrote:
> * Jörn Engel <joern@logfs.org> wrote:
>
> > Result looked like a livelock and finally convinced me to abandon the
> > latency tracer. Sorry, but it appears to be the right tool for the
> > wrong job.
>
> hm, we routinely use it in -rt to capture "what on earth is happening"
> incidents. The snippet below is a random snipped from a trace that i've
> just captured, with mcount enabled. It seems to work fine here, with and
> without mcount. (pit clocksource is almost never used, that's why you
> had those early problems.)
>
> oprofile helps if you can reliably reproduce the slowdown in a loop or
> for a long amount of time, with lots of CPU utilization - and then it's
> also lower overhead. The tracer can be used to capture rare or complex
> events, and gives the full flow control and what is happening within the
> kernel.

Such a trace would be useful indeed. But so far the patch has only
given me grief and nothing remotely like useful output. Maybe I should
simply use the complete -rt patch instead of debugging the broken-out
latency-tracer patch.

Jörn

--
Mundie uses a textbook tactic of manipulation: start with some
reasonable talk, and lead the audience to an unreasonable conclusion.
-- Bruce Perens
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2007-12-02 21:39    [W:0.141 / U:0.508 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site