Simple script to test hard disk speed with dd

ddspeed

#!/bin/bash
# by TB : 2012-10-12

if [ "$USER" != "root" ]
then
	echo "You must be root to execute this script (in order to instruct the kernel to drop the cache)!" 
	exit 1
fi

if [ -z "$1" ]
then 
	TESTFILE=`mktemp -p '.' --suffix '.speedtest'`
else
	DIR="$1"
	[ ! -d "$DIR" ] && { echo "$DIR must be a directory"; exit 1; }
	echo "Are you sure you want to use $DIR as a test file directory. CTRL-C to abort" && read
	TESTFILE=$(mktemp --tmpdir=$DIR)
	
fi

function do_dd_test {
	echo -n "$1 ==>" 
	shift
	#dd $@ 2>&1 | tail -1 | cut -d, -f3
	DD_OUTPUT=`dd $@ 2>&1`
	BITS=1000;
	DD_HUMANIZED=$(echo "$DD_OUTPUT" | sed -r '/.*records /d' | tr -d '()' | awk '{sub(/.*bytes /, $1/'$BITS'/'$BITS'" MB "); sub(/in .* secs/, "in "$5/60" mins "); sub(/mins .*/, "mins (" $7/'$BITS'/'$BITS'" MB/sec)"); printf "%s Gb/s %s MB/s", $1/$6*.008, $1/$6}');
	echo $DD_HUMANIZED
}

trap "{ cleanup; exit 1; }" SIGKILL SIGTERM SIGINT

echo "$d Test `date`"
echo "===================="

for DD_SIZE in "bs=64k count=16k" "bs=1G count=1"; do
	#Drop cache
	echo 3 > /proc/sys/vm/drop_caches
	do_dd_test "WRITE TEST $DD_SIZE" if=/dev/zero of=${TESTFILE} ${DD_SIZE} conv=fdatasync

	#Drop cache
	echo 3 > /proc/sys/vm/drop_caches

	do_dd_test "READ TEST $DD_SIZE (W/O CACHE)"  if=${TESTFILE} of=/dev/null ${DD_SIZE}
	do_dd_test "READ TEST $DD_SIZE (WITH CACHE)" if=${TESTFILE} of=/dev/null ${DD_SIZE}
	rm ${TESTFILE};
done