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How to get percentage of processor use with bash?


I wonder how do I get the percentage of my processor usage from 0% to 100%?

to know how many percent'm using my processor preferably in bash or other methods provided that percentage.

I have this script that I found on google however it is very much imprecisso I tried to make more improvements could not, does anyone know any method to get the percentage of CPU utilization in% 0-100

my script

NUMCPUS=`grep ^proc /proc/cpuinfo | wc -l`; FIRST=`cat /proc/stat | awk '/^cpu / {print $5}'`; sleep 1; SECOND=`cat /proc/stat | awk '/^cpu / {print $5}'`; USED=`echo 2 k 100 $SECOND $FIRST - $NUMCPUS / - p | dc`; echo ${USED}% CPU Usage

Solution

  • Processor use or utilization is a measurement over time. One way to measure utilization in % is by computation over two successive reads of /proc/stat. A simple common bash script to compute the percentage is:

    #!/bin/bash
    
    # Read /proc/stat file (for first datapoint)
    read cpu user nice system idle iowait irq softirq steal guest< /proc/stat
    
    # compute active and total utilizations
    cpu_active_prev=$((user+system+nice+softirq+steal))
    cpu_total_prev=$((user+system+nice+softirq+steal+idle+iowait))
    
    usleep 50000
    
    # Read /proc/stat file (for second datapoint)
    read cpu user nice system idle iowait irq softirq steal guest< /proc/stat
    
    # compute active and total utilizations
    cpu_active_cur=$((user+system+nice+softirq+steal))
    cpu_total_cur=$((user+system+nice+softirq+steal+idle+iowait))
    
    # compute CPU utilization (%)
    cpu_util=$((100*( cpu_active_cur-cpu_active_prev ) / (cpu_total_cur-cpu_total_prev) ))
    
    printf " Current CPU Utilization : %s\n" "$cpu_util"
    
    exit 0
    

    use/output:

    $ bash procstat-cpu.sh
     Current CPU Utilization : 10
    

    output over 5 iterations:

    $ ( declare -i cnt=0; while [ "$cnt" -lt 5 ]; do bash procstat-cpu.sh; ((cnt++)); done )
     Current CPU Utilization : 20
     Current CPU Utilization : 18
     Current CPU Utilization : 18
     Current CPU Utilization : 18
     Current CPU Utilization : 18