On Wed, 2006-12-20 at 13:20 +0000, David Wragg wrote: > "Albert Cahalan" <[EMAIL PROTECTED]> writes: > > On Mon, Dec 18, 2006 at 11:50:08PM +0000, David Wragg wrote: > >> This patch (against 2.6.19/2.6.19.1) 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: http://www.fenrus.org/cstop.stp -- if you want to mail me at work (you don't), use arjan (at) linux.intel.com Test the interaction between Linux and your BIOS via http://www.linuxfirmwarekit.org - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
