Raspberry PI current system info

systat

#!/bin/bash

# systat — Raspberry PI current system info

# For work vcgencmd maybe you should does this actions:
# sudo -i
# usermod -a -G video you_user
# ln -s /opt/vc/bin/vcgencmd /usr/bin/vcgencmd
# echo 'SUBSYSTEM=="vchiq",GROUP="video",MODE="0660"' > /etc/udev/rules.d/10-vchiq-permissions.rules
# exit
# sudo reboot

function convert_to_MHz {
    let value=$1/1000
    echo "$value"
}

function calculate_overvolts {
    let overvolts=${1#*.}-20
    echo "$overvolts"
}

temp=$(vcgencmd measure_temp)
temp=${temp:5:4}

volts=$(vcgencmd measure_volts)
volts=${volts:5:4}

if [ $volts != "1.20" ]; then
    overvolts=$(calculate_overvolts $volts)
fi

minFreq=$(cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_min_freq)
minFreq=$(convert_to_MHz $minFreq)

maxFreq=$(cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq)
maxFreq=$(convert_to_MHz $maxFreq)

freq=$(cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_cur_freq)
freq=$(convert_to_MHz $freq)

governor=$(cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor)

free_data="$(free)"
mem_data="$(echo "$free_data" | grep 'Mem:')"
free_mem="$(echo "$mem_data" | awk '{print $4}')"
buffers="$(echo "$mem_data" | awk '{print $6}')"
cache="$(echo "$mem_data" | awk '{print $7}')"
total_free=$((free_mem + buffers + cache))
used_swap="$(echo "$free_data" | grep 'Swap:' | awk '{print $3}')"

echo "$temp°C | $volts V | $minFreq/$maxFreq/$freq MHz | $governor"
echo "Free mem: $((total_free / 1024)) MB | Swap: $((used_swap / 1024)) MB"

if [[ $used_swap -eq 0 ]]; then
    echo "No swap is in use"
elif [[ $used_swap -lt $total_free ]]; then
    echo "Freeing swap..."
    sudo swapoff -a
    sudo swapon -a
else
    echo "Not enough free memory. Exiting."
    exit 1
fi

exit 0