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@m1st0
Forked from samueljon/toggleHT.sh
Last active May 21, 2019 15:00
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Disable / Enable HyperThreading cores on runtime - linux
#!/bin/bash
# Turn hyperthreading on or off.
HYPERTHREADING=1
RED="\033[0;31m"
GREEN="\033[0;32m"
YELLOW="\033[0;33m"
ENDCOLOR="\033[0m"
function toggleHyperThreading() {
for CPU in /sys/devices/system/cpu/cpu[0-9]*; do
CPUID=`basename ${CPU} | cut -b4-`
printf "${YELLOW}CPU: ${CPUID}${ENDCOLOR}\t"
[ -e ${CPU}/online ] && printf "1" > ${CPU}/online
THREAD1=`cat ${CPU}/topology/thread_siblings_list | cut -f1 -d,`
if [ ${CPUID} = ${THREAD1} ]; then
printf "${GREEN}-> enable${ENDCOLOR}\n"
[ -e ${CPU}/online ] && printf "1" > ${CPU}/online
else
if [ "${HYPERTHREADING}" -eq "0" ]; then printf "${YELLOW}-> disabled${ENDCOLOR}\n"; else printf "${GREEN}-> enable${ENDCOLOR}\n"; fi
printf "${HYPERTHREADING}" > ${CPU}/online
fi
done
}
function enabled() {
printf "${GREEN}Enabling HyperThreading${ENDCOLOR}\n"
HYPERTHREADING=1
toggleHyperThreading
}
function disabled() {
printf "${YELLOW}Disabling HyperThreading${ENDCOLOR}\n"
HYPERTHREADING=0
toggleHyperThreading
}
function check_privilege() {
WHOAMI=$(/usr/bin/whoami)
if [ "${WHOAMI}" != "root" ] ; then
printf "${RED}Script must be run with proper user priviledges.${ENDCOLOR}\n"
exit 1
fi
}
ONLINE=$(cat /sys/devices/system/cpu/online)
OFFLINE=$(cat /sys/devices/system/cpu/offline)
printf "${YELLOW}%s\n" "---------------------------------------------------"
printf "CPU's online: ${GREEN}${ONLINE}${YELLOW}\t CPU's offline: ${RED}${OFFLINE}\n"
printf "${YELLOW}%s${ENDCOLOR}\n" "---------------------------------------------------"
check_privilege
read -p "Type in e to enable or d disable hyperThreading or q to quit [e/d/q] ?" ed
case ${ed} in
[Ee]* ) enabled; exit;;
[Dd]* ) disabled; exit;;
[Qq]* ) exit;;
* ) printf "${YELLOW}Please answer e for enable or d for disable hyperThreading.${ENDCOLOR}\n";;
esac
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