A script to monitor IO activities

This follows my discussion posted earlier regarding iostat. The script given below might be helpful in monitoring a device that has the given directory in it.

#!/bin/ksh

# This script will print IO activity for the partition given in the argument.
# If no partition is given, it will print IO activity for the partition
# that contains the current directory.
#

if [ -z "$1" ] ; then
DIR=`pwd`
else
DIR="$1"
fi

ORIG_DIR=$DIR
while [ "$DIR" != "/" -a "$DIR" != "." ] ; do
MDEV=`mount -p | grep $DIR | nawk '{print $1;}'`
if [ ! -z "$MDEV" ] ; then
  MDEV=`basename $MDEV`
  break
else
  DIR=`dirname $DIR`
fi
done

if [ -z "$MDEV" ] ; then
echo "Unable to find out the mounted device for $ORIG_DIR."
exit 1
fi

echo "Mounted device for $ORIG_DIR is $MDEV"

iostat -x -p -n -z 5 | egrep "$MDEV|device"

This script was tested in SunOS 5.9 running ksh.

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