lkml.org 
[lkml]   [2007]   [Jul]   [8]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: v2.6.21.5-rt19
    Fernando Lopez-Lezcano wrote:
    > On Sat, 2007-07-07 at 11:24 +0200, Ingo Molnar wrote:
    >
    >> * Fernando Lopez-Lezcano <nando@ccrma.Stanford.EDU> wrote:
    >>
    >>>>> Changes since 2.6.21.5-rt18:
    >>>>>
    >>>>> - Fixed a nasty and hard to track down slowness / boot problem on SMP
    >>>>> machines with CONFIG_NOHZ enabled. The problem was caused by the timer
    >>>>> wheel base lock held during the get_next_timer_interrupt() call in the
    >>>>> idle path, which eventually led to a bogus PI boosting of the idle task
    >>>>> and in consequence a stale wrong scheduler selection for the affected idle
    >>>>> task.
    >>>>>
    >>>>> Kudos to Carsten Emde, who patiently and meticulously isolated the
    >>>>> problem and provided the traces, which allowed to identify the root cause.
    >>>>>
    >>>>> Problem solution: Prevent idle task boosting
    >>>>>
    >>>> Maybe someone remember me whining about troubles with 2.6.21-rt2..18
    >>>> on my Core2 T7200 laptop (fujitsu-siemens amilo i1520).
    >>>>
    >>>> Althought I'm still with my fingers crossed, I can tell the good
    >>>> news are that 2.6.21.5-rt19 (and -rt20) does behave far better now
    >>>> on the very same box.
    >>>>
    >>> Yes, it works much better indeed...
    >>>
    >>> Ingo: is there a place where I can read about the changes in different
    >>> rtxx releases? What is new/better/fixed in rt20? (I see scheduler
    >>> stuff in a diff from rt19 to rt20 but I don't really know what it
    >>> means).
    >>>
    >> and rt18 was a -rt-only NOHZ fix, that bug got introduced in rt11 when
    >> CFS was merged.
    >>
    >> i _think_ Rui might have seen two separate problems. Perhaps by the time
    >> we fixed the first problem (which Rui saw since -rt2) we introduced the
    >> other one via -rt11 - which then got fixed in -rt19.
    >>
    >
    > Ahh, CFS is now part of rt, I was obviously not paying attention... I'm
    > really trying to provide a "stable" rt kernel for audio usage and
    > including another subsystem into rt is - IMHO - not going to help.
    > What's the chance of splitting things?
    >
    >
    >> btw., we'd love to get more feedback regarding CFS. CFS is a completely
    >> new scheduler for Linux.
    >>
    >
    > Then I'd rather have it separate from rt.
    >
    >
    >> It has a design centered around keeping
    >> application latencies down, so it is ultimately real-time friendly, and
    >> it should also make things work better for desktop-ish and audio-ish
    >> stuff as well. (even under SCHED_OTHER)
    >>
    >
    > Maybe this is CFS related? (tail of a thread in the Planet CCRMA mailing
    > list):
    >
    > On Sun, 2007-07-08 at 15:26 -0400, Hector Centeno wrote:
    >
    >> Ok, so just to confirm, that 2.6.21-0182.rt19.1.fc7.ccrmart works fine
    >> on my desktop but on my laptop it makes Firefox and Tomboy to crash.
    >> On the same laptop using 2.6.21-0182.rt17.1.fc7.ccrmart there is no
    >> problem.
    >>
    >> Cheers,
    >>
    >> Hector
    >>
    >>
    >> On 7/7/07, Hector Centeno <hcengar@gmail.com> wrote:
    >> Hi Fernando,
    >>
    >> I do have Flash installed but for me Firefox crashes when
    >> trying to
    >> access gmail (which AFAIK doesn't use Flash, does it?). Right
    >> now
    >> Firefox is frozen and I'm typing this email using Konkeror (in
    >> Gnome).
    >> This is ps' output:
    >>
    >> hector 3595 1.1 2.2 194352 46336 ? D 16:25
    >> 0:03
    >> /usr/lib/firefox-2.0.0.4/firefox-bin
    >>
    >> I think the problem is not present in my Desktop but I have to
    >> double
    >> check. In the same laptop using the stock fedora kernel both
    >> Tomboy
    >> and Firefox work fine. My laptop has a centrino duo processor,
    >> 2 gigs
    >> of ram and the Inte GMA950 graphics chip.
    >>
    >> Hector
    >>
    >
    > I managed to completely hang firefox (fc7) with flash 9 installed
    > (unkillable even with -9).

    Firefox with flash 9 does not work good , there are a lot bugs reported
    about ( just google ) and it hangs on vanilla or
    whatever other kernels as well. Not only Firefox but also Swiftfox,
    Opera, Epiphany etc.

    The most time Firefox dies when you use flash 9 and close a window or a tab.

    > Does not seem to happen with flash 7.

    Yes flash 7 is fine.

    > Have
    > not tried yet with gmail and flash uninstalled. I'll try to strace it to
    > see when/why it hangs.
    >
    >
    > -- Fernando
    >
    >
    >
    >> So it would be nice if you could keep an extra eye on any scheduling
    >> artifacts or regressions, and make sure your favorite workload is still
    >> handled by the Linux scheduler in the utmost best way. I'd like to hear
    >> about any sort of "scheduling behavior / interactivity" regression you
    >> might see, relative to the vanilla kernel. Or if you can see no such
    >> problems then a line of "it works as well as the previous scheduler" is
    >> important info to us too. Thanks!
    >>
    >
    >
    >


    Regards,

    Gabriel C
    -
    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: 2007-07-09 01:45    [W:0.033 / U:32.564 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site