[lkml]   [2006]   [Dec]   [20]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
    SubjectRe: [PATCH] procfs: export context switch counts in /proc/*/stat
    On Wed, 2006-12-20 at 13:20 +0000, David Wragg wrote:
    > "Albert Cahalan" <> writes:
    > > On Mon, Dec 18, 2006 at 11:50:08PM +0000, David Wragg wrote:
    > >> This patch (against 2.6.19/ adds the four context
    > >> switch values (voluntary context switches, involuntary
    > >> context switches, and the same values accumulated from
    > >> terminated child processes) to the end of /proc/*/stat,
    > >> similarly to min_flt, maj_flt and the time used values.
    > >
    > > Hmmm, OK, do people have a use for these values?
    > My reason for writing the patch was to track which processes are
    > active (i.e. got scheduled to run) by polling these context switch
    > values. The time used values are not a reliable way to detect process
    > activity on fast machines. So for example, when sorting by %CPU, top
    > often shows many processes using 0% CPU, despite the fact that these
    > processes are running occasionally. If top sorted by (%CPU, context
    > switch count delta), it might give a more useful display of which
    > processes are active on the system.

    if all you care is the number of context switches, you can use the
    following system tap script as well:

    if you want to mail me at work (you don't), use arjan (at)
    Test the interaction between Linux and your BIOS via

    To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
    the body of a message to
    More majordomo info at
    Please read the FAQ at

     \ /
      Last update: 2006-12-20 14:53    [W:0.030 / U:10.984 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site