[lkml]   [2011]   [Feb]   [18]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
    SubjectRe: [PATCH 3/3] perf events: add timehist option to record and report
    On Fri, 2011-02-18 at 11:07 -0700, David Ahern wrote:
    > We want not only context-switch events, but the stack trace at the
    > switch.

    Both ftrace and perf can do that:

    perf record -ge sched:sched_switch -c 1


    echo 1 > /debug/tracing/options/stacktrace

    > That data along with the gettimeofday timestamp has allowed us to
    > resolve performance issues such as a system call taking longer than
    > expected during a specific sequence of events or a process getting
    > preempted and not scheduled for N seconds. etc., etc.

    Non of that seems to require GTOD stamps.

     \ /
      Last update: 2011-02-18 19:41    [W:0.040 / U:2.216 seconds]
    ©2003-2017 Jasper Spaans. hosted at Digital OceanAdvertise on this site