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throttling mdworker on osx
#! /bin/bash
# from https://www.facebook.com/notes/netways/wenn-das-macbook-zu-hei%C3%9F-ist-cpulimitsh/10150313173463753/
# Description:
#
# If you want to decrease the CPU demands for an application
# you can use this very simple and ugly "hack".
# I use it when I convert videos on my MacBook Pro
# to prevent it from getting to warm. Even if the CPU is IDLE this hack
# will prevent the application to use the CPU during Sleep Time
# (in contrast to renice/nice commands which will take all IDLE time).
# This means the conversions will take longer time, but I
# don't care because I run it at night.
#
# There is similar c program for Linux called cpulimit, but it wont
# compile on my Mac.
#
# Usage: sudo ./cpulimit.sh
#
#################################
# config
sleeptime_default=0.5 # in seconds
runtimep_default=50 # in percent (50 = same as sleeptime)
reporttime=30 # report every x seconds while running
# PROCESSLISTformat: pid has to be on the second position
PROCESSLISTformat="ppid,pid,user,%cpu,%mem,start,cputime,stime,command"
#PROCESSLISTformat="ppid,pid,user,%cpu,%mem,start,cputime,stime,rss,vsz,cpu,re,wq,wqr,stat,nsigs,command"
#################################
# dont change anything below here
pid=""
scriptuser=$(id -u)
# run if user hits control-c
control_c()
{
echo ""
if [ "$pid" != "" ]; then
echo -en "\n*** Ouch! Stop throtteling of PID $pid. Exiting ***\n"
kill -SIGCONT $pid
fi
echo ""
exit $?
}
# trap keyboard interrupt (control-c)
trap control_c SIGINT
pidstring()
{
# takes pid as argument
ps -p $1 -w -o pid,user,%cpu,%mem,start,cputime,command 2>/dev/null
}
isnumber()
{
if [[ "$1" =~ ^[0-9]*([.][0-9]+)?$ ]] ; then
return 0
else
return 1
fi
}
#################################
# main
cat << EOF
This script will throttle a chosen process as you like it.
Therefore your cpu runs cooler - hopefully.
EOF
if [ "$scriptuser" != "0" ]; then
cat << EOF
You're not root!
If you want to controll processes that you dont own,
please run via sudo.
EOF
fi
PIDSTRING=""
until [ "$PIDSTRING" != "" ]; do
#PROCESSLIST=$(ps -r -A -f -S | head)
if [ "$scriptuser" != "0" ]; then
PROCESSLIST=$(ps -r -u $scriptuser -S -c -o $PROCESSLISTformat 2>/dev/null)
else
PROCESSLIST=$(ps -r -A -S -c -o $PROCESSLISTformat 2>/dev/null)
fi
if [ "$PROCESSLIST" = "" ]; then
echo -en "\n*** Sorry, ps dont work as expected on $(uname). Exiting ***\n\n"
exit 1
else
PROCESSLIST=$(echo "$PROCESSLIST" | head)
fi
echo -en "\nChose which process to throttle:\n$PROCESSLIST\n"
PID_GUESS=$(echo "$PROCESSLIST" | head -2 | tail -1 | awk '{print $2}')
echo -n "Which process ID (PID) [guess: $PID_GUESS]? "
read pid
if [ "$pid" = "" ]; then
pid=$PID_GUESS
fi
# test if $pid is valid
PIDSTRING=$(pidstring $pid)
if [ "$?" -eq "0" ]; then
echo -en "\nChosen:\n$PIDSTRING\n"
else
echo -en "\n$pid is not a valid PID for a running process.\n"
pid=""
fi
echo -en "\n"
done
sleeptime=""
until [ "$sleeptime" != "" ]; do
echo -n "Sleep time in seconds (e.g 0.5 or 1 …) [default: $sleeptime_default]? "
read sleeptime
if [ "$sleeptime" = "" ]; then
sleeptime=$sleeptime_default
fi
isnumber $sleeptime || sleeptime=""
done
#echo "sleeptime $sleeptime"
runtime=""
until [ "$runtime" != "" ]; do
runtime_default=$(echo "scale=4;$sleeptime*$runtimep_default/(100-$runtimep_default)"|bc)
echo -n "Run time in seconds (e.g 0.5 or 1 …) or percent [default: $runtime_default = $runtimep_default%]? "
read runtime
if [[ "$runtime" =~ ^([0-9]*([.][0-9]+)?)%$ ]] ; then
runtimep_default=${BASH_REMATCH[1]}
fi
if [ "$runtime" = "" ]; then
runtime=$runtime_default
fi
isnumber $runtime || runtime=""
done
#echo "runtime $runtime"
# now begin throttle
throttletime=1000000
looptime=$(awk "BEGIN { printf \"%.0f\\n\", ($sleeptime+$runtime)*100 }")
echo "OK. I will throttle PID $pid now and dislay processinfo every $reporttime seconds … "
((reporttime=$reporttime*100))
while true
do
if [ $throttletime -ge 500 ]; then
throttletime=0
PIDSTRING=$(pidstring $pid)
echo "$PIDSTRING"
fi
kill -SIGSTOP $pid || control_c
sleep $sleeptime
kill -SIGCONT $pid || control_c
sleep $runtime
throttletime=$(($looptime+$throttletime))
done
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