lkml.org 
[lkml]   [2005]   [Oct]   [11]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    SubjectRe: Latency data - 2.6.14-rc3-rt13
    From
    Date
    On Mon, 2005-10-10 at 20:45 -0700, Mark Knecht wrote:
    > On 10/10/05, Mark Knecht <markknecht@gmail.com> wrote:
    > >
    > > ( softirq-timer/0-3 |#0): new 3997 us maximum-latency critical section.
    >
    > So the root cause of this 4mS delay is the 250Hz timer. If I change
    > the system to use the 1Khz timer then the time in this section drops,
    > as expected, to 1mS.
    >
    > ( softirq-timer/0-3 |#0): new 998 us maximum-latency critical section.
    > => started at timestamp 121040020: <acpi_processor_idle+0x20/0x379>
    > => ended at timestamp 121041019: <thread_return+0xb5/0x11a>
    >
    > So, thinking very interesting here I think.
    >

    Maximum preemption latencies near the timer period
    are sometimes indicative of mismatched
    preempt_disable/preempt_enable pairs in the code.

    Usually the scheduler warns about that on the console, however.

    Sven

    > Back to the drawing board as to my xruns.
    >
    > - Mark
    > -
    > 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/
    --
    ***********************************
    Sven-Thorsten Dietrich
    Real-Time Software Architect
    MontaVista Software, Inc.
    1237 East Arques Ave.
    Sunnyvale, CA 94085

    Phone: 408.992.4515
    Fax: 408.328.9204

    http://www.mvista.com
    Platform To Innovate
    ***********************************

    -
    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: 2005-10-11 10:58    [W:0.037 / U:3.332 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site