parses iostat to give iowait, reads and writes (Blk_read Blk_wrtn) in a specific way that I wanted it to at one point on some day or other.

iostatparse

#!/bin/bash
vg=vg_backup-lv_backup
numlines=50

geta() {
                a=()
                 while read -d $'\n'; do
                        a+=("$REPLY")
                 done < <(echo "$@" | tail -n 6| grep -A2 iowait  | awk '{ print $4 }'  | sed 's,\,,,g' | grep -o '[0-9]*' | sed 's/.$//')
}
getb() {
                b=()
                 while read -d $'\n'; do
                        b+=("$REPLY")
                 done < <(echo "$@" | tail -n 6 | grep $vg | awk '{ print $3 }' |sed 's/...$//')
}

getc() {
                c=()
                 while read -d $'\n'; do
                        c+=("$REPLY")
                 done < <(echo "$@" | tail -n 6 | grep $vg | awk '{ print $4 }' |sed 's/...$//')
}

zz=0
while (( zz < $numlines ));
do
x="$(iostat 1 2 -N $vg)"
geta "$x"
getb "$x"
getc "$x"
    echo "reads "${b[@]}" iowait  "${a[@]}" writes "${c[@]}""
(( zz++ ))
done