#!/bin/bash

[ -z $1 ] && echo -e "Usage: $0 <file> [delay] [#lines] appends iostats for raw drives to\n" \
                     "       file w/header every #lines lines , and tees out to stdout" && exit


delay=15
[ -n $2 ] && delay=$2

lines=40
[ -n $3 ] && lines=$3

while :; do
  ( echo
  echo -e "`date "+%Y%m%d %H%M%S"`\ndrv   rrqm/s   wrqm/s     r/s     w/s    rkB/s   wkB/s avgrq-sz avgqu-sz  await  svctm  %util"
  iostat -kxd -t $delay $lines | egrep --line-buffered --color "^sda.*$|sd[a-z] " ) |
  tee -a "$1"  
done
