[Redmi Note 2 General] DarthJabba9:
How about this script for on-the-fly speed/battery tweaks? (it needs to be run from a terminal prompt, and must be run as superuser);

#!/system/bin/sh

# ---------------------------------------
# Redmi Note 2 cpu stuff (DarthJabba9)
# Must be run as superuser
# ---------------------------------------

syntax()
{
echo "Syntax = $0 <code>"
echo "Codes: "
echo " 0 = battery saver mode (1.2Ghz Max)"
echo " 1 = balanced mode (1.6Ghz Max)"
echo " 2 = performance mode (1.9Ghz Max)"
exit 1
}

Write()
{
echo $2 > $1
}

# no argument - halt
[ -z "$1" ] && syntax

# default to "Balanced"
code=1
[ "$1" = "0" ] || [ "$1" = "1" ] || [ "$1" = "2" ] && {
code=$1
}

# Tweak Entropy (thanks to jajk and Namaless)
Write /proc/sys/kernel/random/read_wakeup_threshold "2048"
Write /proc/sys/kernel/random/write_wakeup_threshold "4096"

# cpu tweaks (thanks to CM team, and jajk)

# Battery saver
Battery_saver()
{
Write /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq "1183000"
Write /sys/devices/system/cpu/cpu1/cpufreq/scaling_max_freq "1183000"
Write /sys/devices/system/cpu/cpu0/cpufreq/scaling_min_freq "403000"
Write /sys/devices/system/cpu/cpu1/cpufreq/scaling_min_freq "403000"
Write /sys/devices/system/cpu/cpufreq/interactive/target_loads '90 403000:84 806000:92 1100000:96 1183000:99'
Write /proc/cpufreq/cpufreq_limited_max_freq_by_user "1183000"
Write /sys/devices/system/cpu/cpu3/online "1"
Write /sys/devices/system/cpu/cpu4/online "0"
Write /sys/devices/system/cpu/cpu5/online "0"
Write /sys/devices/system/cpu/cpu6/online "0"
Write /sys/devices/system/cpu/cpu7/online "0"
exit 0
}

# Balanced
Balanced()
{
Write /sys/devices/system/cpu/cpu3/online "1"
Write /sys/devices/system/cpu/cpu4/online "1"
Write /sys/devices/system/cpu/cpu5/online "1"
Write /sys/devices/system/cpu/cpu6/online "1"
Write /sys/devices/system/cpu/cpu7/online "1"
Write /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq "1650000"
Write /sys/devices/system/cpu/cpu1/cpufreq/scaling_max_freq "1650000"
Write /sys/devices/system/cpu/cpu0/cpufreq/scaling_min_freq "403000"
Write /sys/devices/system/cpu/cpu1/cpufreq/scaling_min_freq "403000"
Write /sys/devices/system/cpu/cpufreq/interactive/target_loads '90 403000:70 806000:80 1183000:84 1326000:88 1469000:92 1625000:96 1650000:99'
Write /proc/cpufreq/cpufreq_limited_max_freq_by_user "1650000"
exit 0
}

# Performance
Performance()
{
Write /sys/devices/system/cpu/cpu3/online "1"
Write /sys/devices/system/cpu/cpu4/online "1"
Write /sys/devices/system/cpu/cpu5/online "1"
Write /sys/devices/system/cpu/cpu6/online "1"
Write /sys/devices/system/cpu/cpu7/online "1"
Write /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq "1950000"
Write /sys/devices/system/cpu/cpu1/cpufreq/scaling_max_freq "1950000"
Write /sys/devices/system/cpu/cpu0/cpufreq/scaling_min_freq "806000"
Write /sys/devices/system/cpu/cpu1/cpufreq/scaling_min_freq "806000"
Write /sys/devices/system/cpu/cpufreq/interactive/target_loads '90 403000:70 806000:80 1183000:84 1326000:88 1469000:92 1650000:96 1950000:99'
Write /proc/cpufreq/cpufreq_limited_max_freq_by_user "1950000"
exit 0
}

case "$code" in
0)
Battery_saver > /dev/null 2>&1
Battery_saver
;;
1)
Balanced > /dev/null 2>&1
Balanced
;;
2)
Performance > /dev/null 2>&1
Performance
;;
*)
syntax
;;
esac

Here are some Geekbench 3 benchmarks:

Saver:

single-core 598

multi-core 3154

Balanced:

single-core 770

multi-core 4023

Performance:

single-core 874

multi-core 4375

Normal (i.e., no tweaks):

single-core 885

multi-core 4460