Read/Write Performance Benchmark with dd

Trying to measure the read/write performance of a Patriot Xporter XT Boost 16GB USB Flash drive, I came up with a bash script. The Xporter XT Boost performance is:

  write:  13.40 MB/s
   read:  27.27 MB/s

Note: above 1 MB/s corresponds to 1024*1024 bytes/s. In dd 1 MB/s corresponds to 1000*1000 bytes/s. Interesting to note is that the sync mount option kills the performance, therefore the script:

#!/bin/bash

GB_COUNT=3
GB_SIZE=1000
MOUNT_OPTIONS="-o flush,uid=$UID"

flash_device=$1
flash_mount_point=/tmp/$RANDOM

READSPEED=0
WRITESPEED=0

function mount_flash {
  mounted=$(mount -l | grep $flash_device)
  if [ -z "$mounted" ]
  then
    echo "mounting..."
     sudo mount $MOUNT_OPTIONS $flash_device $flash_mount_point
    fi
}
function umount_flash {
  UNMOUNTING=$(date +%s)

  mounted=$(mount -l | grep $flash_device)
  while [ ! -z "$mounted" ]
  do
    echo "unmounting $flash_device ..."
    sudo umount $flash_device
    mounted=$(mount -l | grep $flash_device)
  done


  UNMOUNTED=$(date +%s)
  echo "! device $flash_device unmounted in $(($UNMOUNTED-$UNMOUNTING)) sec"
}

function init {
  mkdir -p $flash_mount_point
  if [ -z "$flash_device" ] || [ ! -b "$flash_device" ]
  then
    echo "Invalid device specified:[$flash_device]"
    exit
  fi

  umount_flash
  mount_flash
  echo ""
  echo "     Read/Write Benchmark"
  echo "=============================="
  echo "!   device:  $flash_device"
  echo "!  mounted:  $(sudo mount -l | grep $flash_device)"
  echo "!" 
  echo "=============================="
  echo ""
}

function write_test {
  mount_flash

  START=$(date +%s)

  for i in $(seq 1 1 $GB_COUNT)
  do
    echo "  writing $GB_SIZE MB: $i of $GB_COUNT"
    dd count=$GB_SIZE bs=1M if=/dev/zero of=$flash_mount_point/test.$i
  done

  echo "! unmounting.."
  umount_flash

  END=$(date +%s)
  TIME=$(($END-$START))

  echo "! writting $(($GB_COUNT*$GB_SIZE)) MB  done in: $TIME sec"
  echo ""

  integ=$(($GB_SIZE*$GB_COUNT/$TIME))
  frac=$((100*$GB_SIZE*$GB_COUNT/$TIME-100*$integ))
  WRITESPEED=$integ.$frac
  echo "! write: $WRITESPEED MB/s"
}

function read_test {
  mount_flash
  START=$(date +%s)

  for i in $(seq 1 1 $GB_COUNT)
  do
    echo "  reading $GB_SIZE MB: $i of $GB_COUNT"
    dd count=1000 bs=1M of=/dev/null if=$flash_mount_point/test.$i
  done

  umount_flash

  END=$(date +%s)
  TIME=$(($END-$START))

  echo "! reading $(($GB_COUNT*$GB_SIZE)) MB done in: $TIME sec"
  echo ""

  integ=$(($GB_SIZE*$GB_COUNT/$TIME))
  frac=$((100*$GB_SIZE*$GB_COUNT/$TIME-100*$integ))
  READSPEED=$integ.$frac
  echo "! read: $READSPEED MB/s"
}


init
write_test
read_test

echo "======================"
echo "  Benchmark Result:"
echo ""

echo "  write:  $WRITESPEED MB/s"
echo "   read:  $READSPEED MB/s"

echo ""
echo "======================"

Worth reading - http://www.hjreggel.net/cardspeed