dd if=/dev/zero of=/tmp/output bs=8k count=10k; rm -f /tmp/output
fio --randrepeat=1 --ioengine=libaio --direct=1 --gtod_reduce=1 --name=test --filename=test --bs=4k --iodepth=64 --size=2G --readwrite=randrw --rwmixread=75; rm -rf test;
https://askubuntu.com/questions/87035/how-to-check-hard-disk-performance/87036#87036