-#!/bin/bash
+#!/bin/sh
############################################################################
#
# Function definitions #
#########################
-function usage {
+usage() {
echo "Usage: $0 [-a] [-d] [-i <i>] [-n] [-r] [-s <l2s>] <dev>"
echo " -a - use asynchronous (buffered) I/O."
echo " -d - use direct (non-buffered) I/O."
echo " <dev> - block device to run the I/O performance test on."
}
-function drop_caches {
+# Echo ((2**$1))
+pow2() {
+ if [ $1 = 0 ]; then
+ echo 1
+ else
+ echo $((2 * $(pow2 $(($1 - 1)) ) ))
+ fi
+}
+
+drop_caches() {
sync
if [ -w /proc/sys/vm/drop_caches ]; then
echo 3 > /proc/sys/vm/drop_caches
# using format $1, and also echo the average transfer size in MB/s, its
# standard deviation and the number of IOPS using the total I/O size $2 and
# the block transfer size $3.
-function echo_and_calc_avg {
- awk -v fmt="$1" -v iosize="$2" -v blocksize="$3" '{if ($1 != 0){n++;sum+=iosize/$1;sumsq+=iosize*iosize/($1*$1)};printf fmt, $1} END{d=(n>0?sumsq/n-sum*sum/n/n:0);avg=(n>0?sum/n:0);stddev=(d>0?sqrt(d):0);iops=avg/blocksize;printf fmt fmt fmt,avg/2**20,stddev/2**20,iops}'
+echo_and_calc_avg() {
+ awk -v fmt="$1" -v iosize="$2" -v blocksize="$3" 'BEGIN{pow_2_20=1024*1024}{if ($1 != 0){n++;sum+=iosize/$1;sumsq+=iosize*iosize/($1*$1)};printf fmt, $1} END{d=(n>0?sumsq/n-sum*sum/n/n:0);avg=(n>0?sum/n:0);stddev=(d>0?sqrt(d):0);iops=avg/blocksize;printf fmt fmt fmt,avg/pow_2_20,stddev/pow_2_20,iops}'
}
#########################
# Argument processing #
#########################
-set -- $(/usr/bin/getopt "adi:nrs:" "$@")
+set -- $(/usr/bin/getopt "adhi:nrs:" "$@")
while [ "$1" != "${1#-}" ]
do
case "$1" in
fi
if [ "${read_test_only}" = "false" -a "${verify_device_data}" = "true" ] \
- && ! cmp -s -n $((2**log2_io_size)) "${device}" /dev/zero
+ && ! cmp -s -n $(pow2 $log2_io_size) "${device}" /dev/zero
then
echo "Error: device ${device} still contains data."
exit 1
# Header, line 1
printf "%9s " blocksize
-for ((i = 0; i < ${iterations}; i++))
+i=0
+while [ $i -lt ${iterations} ]
do
printf "%8s " "W"
+ i=$((i+1))
done
printf "%8s %8s %8s " "W(avg," "W(std," "W"
-for ((i = 0; i < ${iterations}; i++))
+i=0
+while [ $i -lt ${iterations} ]
do
printf "%8s " "R"
+ i=$((i+1))
done
printf "%8s %8s %8s" "R(avg," "R(std" "R"
printf "\n"
# Header, line 2
printf "%9s " "(bytes)"
-for ((i = 0; i < ${iterations}; i++))
+i=0
+while [ $i -lt ${iterations} ]
do
printf "%8s " "(s)"
+ i=$((i+1))
done
printf "%8s %8s %8s " "MB/s)" ",MB/s)" "(IOPS)"
-for ((i = 0; i < ${iterations}; i++))
+i=0
+while [ $i -lt ${iterations} ]
do
printf "%8s " "(s)"
+ i=$((i+1))
done
printf "%8s %8s %8s" "MB/s)" ",MB/s)" "(IOPS)"
printf "\n"
# Measurements
-for ((log2_blocksize = log2_max_blocksize;
- log2_blocksize >= log2_min_blocksize;
- log2_blocksize--))
+log2_blocksize=${log2_max_blocksize}
+while [ ! $log2_blocksize -lt $log2_min_blocksize ]
do
if [ $log2_blocksize -gt $log2_io_size ]; then
continue
fi
- iosize=$((2**log2_io_size))
- bs=$((2**log2_blocksize))
- count=$((2**(log2_io_size - log2_blocksize)))
+ iosize=$(pow2 $log2_io_size)
+ bs=$(pow2 $log2_blocksize)
+ count=$(pow2 $(($log2_io_size - $log2_blocksize)))
printf "%9d " ${bs}
- for ((i = 0; i < ${iterations}; i++))
+ i=0
+ while [ $i -lt ${iterations} ]
do
if [ "${read_test_only}" = "false" ]; then
drop_caches
else
echo 0
fi
+ i=$((i+1))
done | echo_and_calc_avg "%8.3f " ${iosize} ${bs}
- for ((i = 0; i < ${iterations}; i++))
+ i=0
+ while [ $i -lt ${iterations} ]
do
drop_caches
dd if="${device}" of=/dev/null bs=${bs} count=${count} \
${dd_iflags} 2>&1 \
| sed -n 's/.* \([0-9.]*\) s,.*/\1/p'
+ i=$((i+1))
done | echo_and_calc_avg "%8.3f " ${iosize} ${bs}
printf "\n"
+ log2_blocksize=$((log2_blocksize - 1))
done