dd testing script

run_dd.sh

#!/bin/bash

if [ $# -lt 2 ]; then
  echo "usage:$0 dev output_dir"
  exit 1
fi

DEV="$1"
OUTDIR="$2"
DATASIZE="500" # in MB

mkdir -p $OUTDIR

BLOCK_SIZES="8192 262144"

function run_test()
{
  local rc=
  block_size=$1
  count=`echo "$DATASIZE*1048576/$block_size"|bc`

  echo "doing write in ${block_size}B"
  rc=$(dd if=/dev/zero of=$DEV bs=$block_size count=$count oflag=direct 2>&1)
  echo $rc
  echo $rc >"$OUTDIR/dd.write.$block_size.log"

  echo
  echo "doing read in ${block_size}B"
  rc=$(dd of=/dev/null if=$DEV bs=$block_size count=$count iflag=direct 2>&1)
  echo $rc
  echo $rc >"$OUTDIR/dd.read.$block_size.log"
}

# run all the jobs
for block_size in $BLOCK_SIZES
do
  run_test $block_size
done