dwm/xsetroot.d/load.sh

load_representation=(░ ▒ ▓ █)
thresholds=(0 16.7 50 83.3 100)

# Requires mpstat from the sysstat package.
load() {
    nboxes=$(nproc)
    load=$(awk '{print $1}' /proc/loadavg)
    loads=$(mpstat -P ALL -u 5 1 | tail -$nboxes | awk '{print 100-$NF}' | sort -n -r)
    for L in $loads; do
        for level in $(seq 0 ${#load_representation[*]}); do
            test_str="$L >= ${thresholds[$level]} && $L <= ${thresholds[$(( level + 1 ))]}"
            if (( $(bc -l <<< "${test_str}") )); then
                printf "%s" "${load_representation[$level]}"
                break
            fi
        done
    done
}

load_file=/tmp/load_summary
while true; do
    load > "$load_file"
    sleep 1
done &

show_load() {
    cat "$load_file"
}

register+=('show_load')