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jondkent

Member

From: London

Registered: 2005-09-13

Posts: 123

strace query

Hi,

I just wanna ensure that I'm being sane here.  I've put together the following script

#!/bin/sh
#
# 
# Script to get either process CPU affinity
# or scheduler class
#

while getopts "p:sah" opt; do
        case "$opt" in
                p ) proc="$OPTARG"      ;;
                s ) sched="on"          ;;
                a ) afin="on"           ;;
                h ) echo "Usage: $0 -p [pid] -s -a"
                    echo "-s = get process scheduling class"
                    echo "-a = get process cpu affinity"; echo
                    exit 1
        esac
done

if [ -z "$proc" ] ; then
        echo "No pid entered...exiting"
        exit 1
fi

if [ -n "$sched" ] ; then
        echo
        echo "Getting scheduler for $proc"
        strace -etrace=sched_getscheduler chrt -p $proc
fi

if [ -n "$afin" ] ; then
        echo
        echo "Getting CPU affinity mask for $proc"
        strace -etrace=sched_getaffinity taskset -p $proc
fi

echo

The idea behind it is that I wanna get back the CPU affinity and scheduler class for an existing process.  This strace commands seem to work but I still wanna be sure that my reasoning is sound, in other words is strace query the running process?

Thanks for any feedback

Jon