ext-cryptopp/TestScripts/governor.sh
2017-10-08 14:12:16 -04:00

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1.5 KiB
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#!/usr/bin/env bash
# This scripts queries and modifies CPU scaling frequencies to produce more
# accurate benchmark results. To move from a low energy state C-state to a
# higher one, run 'governor.sh performance'. To move back to a low power state
# run 'governor.sh powersave' or reboot. The script is based on code by
# Andy Polyakov, http://www.openssl.org/~appro/cryptogams/.
if [ "x$1" = "x" ]; then
echo "usage: $0 on[demand]|pe[rformance]|?"
[[ "$0" = "$BASH_SOURCE" ]] && exit 1 || return 1
fi
# "on demand" may result in a "invalid write argument" or similar
case $1 in
on*|de*) governor="ondemand";;
po*|pw*) governor="powersave";;
pe*) governor="performance";;
us*) governor="userspace";;
\?) ;;
*) echo "$1: unrecognized governor";;
esac
if [ -z "$governor" ]; then
[[ "$0" = "$BASH_SOURCE" ]] && exit 1 || return 1
fi
cpus=$(ls /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor 2>/dev/null)
if [ -z "$cpus" ]; then
echo "Failed to read CPU system device tree"
[[ "$0" = "$BASH_SOURCE" ]] && exit 1 || return 1
fi
echo "Current CPU governor scaling settings:"
count=0
for cpu in $cpus; do
echo " CPU $count:" $(cat "$cpu")
((count++))
done
if [ "x$governor" != "x" ]; then
for cpu in $cpus; do
echo $governor > $cpu
done
fi
echo "New CPU governor scaling settings:"
count=0
for cpu in $cpus; do
echo " CPU $count:" $(cat "$cpu")
((count++))
done
[[ "$0" = "$BASH_SOURCE" ]] && exit 0 || return 0