$ sudo fio --bs=4k --ioengine=libaio --iodepth=32 --size=500m --direct=1 --runtime=60 --filename=/dev/sdf --rw=randwrite --numjobs=1 --name=test test: (g=0): rw=randwrite, bs=(R) 4096B-4096B, (W) 4096B-4096B, (T) 4096B-4096B, ioengine=libaio, iodepth=32 fio-3.16 Starting 1 process Jobs: 1 (f=1): [w(1)][100.0%][w=1733KiB/s][w=433 IOPS][eta 00m:00s] test: (groupid=0, jobs=1): err= 0: pid=12944: Sat Jun 19 14:49:58 2021 write: IOPS=421, BW=1685KiB/s (1725kB/s)(98.9MiB/60118msec); 0 zone resets [ ... ] Run status group 0 (all jobs): WRITE: bw=1685KiB/s (1725kB/s), 1685KiB/s-1685KiB/s (1725kB/s-1725kB/s), io=98.9MiB (104MB), run=60118-60118msec Disk stats (read/write): sdf: ios=51/25253, merge=0/0, ticks=7/1913272, in_queue=1862556, util=99.90%