Zero dependency linux IO usage checker

iocheck.sh

#!/bin/sh

INTERVAL=10
PARTITION=mmcblk0p2
DEVICE=mmcblk0

#PARTITION=sda2
#DEVICE=sda

S_SIZE=`cat /sys/block/$DEVICE/queue/hw_sector_size`

while getopts "h?i:" opt; do
    case "$opt" in
    h|\?)
        show_help
        exit 0
        ;;
    i)  INTERVAL=$OPTARG
        if [ $INTERVAL -lt 1 ];then
            echo "You wanted an INTERVAL of $INTERVAL, but must be greater than
1"
            exit 1
        fi
        ;;
    esac
done

show_help ()
{
    echo "Usage: -i <INTERVAL in seconds>"
    echo "Example: ./bw.sh -i 5"
    echo "The longer the INTERVAL, the more accurate the average. Minimum is 1,
default is 10".
}

check_net ()
{
    cat /proc/net/netstat | grep 'IpExt: ' | tail -n 1 | awk '{ print $8 "\t" $9 }'
}

check_disk ()
{
    cat /proc/diskstats  | grep $PARTITION | awk '{print $9 "\t" $13 }'
}

NET_START=`check_net`
NET_IN_START=`echo $NET_START | awk '{ print $1 }'`
NET_OUT_START=`echo $NET_START | awk '{ print $2 }'`


DISK_START=`check_disk`
DISK_IN_START=`echo $DISK_START | awk '{ print $1 }'`
DISK_OUT_START=`echo $DISK_START | awk '{ print $2 }'`


sleep $INTERVAL

NET_END=`check_net`
NET_IN_END=`echo $NET_END | awk '{ print $1 }'`
NET_OUT_END=`echo $NET_END | awk '{ print $2 }'`

DISK_END=`check_disk`
DISK_IN_END=`echo $DISK_END | awk '{ print $1 }'`
DISK_OUT_END=`echo $DISK_END | awk '{ print $2 }'`



NET_IN_BPS=`awk -v s=$NET_IN_START -v e=$NET_IN_END 'BEGIN { print ( ( e - s ) / 10^6 ) }'`
NET_OUT_BPS=`awk -v s=$NET_OUT_START -v e=$NET_OUT_END 'BEGIN { print ( ( e - s ) / 10^6 )
}'`
NET_TOTAL_BPS=`awk -v i=$NET_IN_BPS -v o=$NET_OUT_BPS 'BEGIN { print i + o }'`


DISK_IN_BPS=`awk -v s=$DISK_IN_START -v e=$DISK_IN_END 'BEGIN { print ( ( e - s ) / 10^6 ) }'`
DISK_OUT_BPS=`awk -v s=$DISK_OUT_START -v e=$DISK_OUT_END 'BEGIN { print ( ( e - s ) / 10^6 )
}'`
DISK_TOTAL_BPS=`awk -v i=$DISK_IN_BPS -v o=$DISK_OUT_BPS 'BEGIN { print i + o }'`


TOTAL_BPS=`awk -v i=$DISK_TOTAL_BPS -v o=$NET_TOTAL_BPS 'BEGIN { print i + o }'`

echo "Net In: " $NET_IN_BPS "MB/s";
echo "Net Out: " $NET_OUT_BPS "MB/s"
echo "Net Total: $NET_TOTAL_BPS MB/s"

echo "Disk In: " $DISK_IN_BPS "MB/s";
echo "Disk Out: " $DISK_OUT_BPS "MB/s"
echo "Disk Total: $DISK_TOTAL_BPS MB/s"

echo "Total: $TOTAL_BPS MB/s"