HDD Benchmark

good
fio --randrepeat=1 --ioengine=libaio --direct=1 --gtod_reduce=1 --name=test --filename=test --bs=4k --iodepth=64 --size=4G --readwrite=randrw --rwmixread=75
bad
#!/bin/bash

sync
echo 3 > /proc/sys/vm/drop_caches
echo "write test"
dd if=/dev/zero of=./tmp conv=fdatasync bs=384k count=1k

sync
echo 3 > /proc/sys/vm/drop_caches
echo "read test"
dd if=./tmp of=/dev/null bs=384k

rm -f ./tmp