2 # Copyright 2014 the V8 project authors. All rights reserved.
3 # Use of this source code is governed by a BSD-style license that can be
4 # found in the LICENSE file.
6 CPUPATH=/sys/devices/system/cpu
8 MAXID=$(cat $CPUPATH/present | awk -F- '{print $NF}')
11 echo "Setting CPU frequency governor to \"$1\""
12 for (( i=0; i<=$MAXID; i++ )); do
13 echo "$1" > $CPUPATH/cpu$i/cpufreq/scaling_governor
18 echo "Switching to dual-core mode"
19 for (( i=2; i<=$MAXID; i++ )); do
20 echo 0 > $CPUPATH/cpu$i/online
25 echo "Switching to single-core mode"
26 for (( i=1; i<=$MAXID; i++ )); do
27 echo 0 > $CPUPATH/cpu$i/online
33 echo "Reactivating all CPU cores"
34 for (( i=1; i<=$MAXID; i++ )); do
35 echo 1 > $CPUPATH/cpu$i/online
41 set_governor "performance"
44 set_governor "powersave"
47 set_governor "ondemand"
59 echo "Usage: $0 fast|slow|default|singlecore|dualcore|all"