$ sudo fio --bs=4k --ioengine=libaio --iodepth=32 --size=10g --direct=1 --runtime=60 \--filename=/dev/mapper/wc --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-3.12 Starting 1 process Jobs: 1 (f=1): [w(1)][100.0%][eta 00m:00s] test: (groupid=0, jobs=1): err= 0: pid=7055: Sat Oct 12 19:09:53 2019 write: IOPS=34.8k, BW=136MiB/s (143MB/s)(9.97GiB/75084msec); 0 zone resets [ ... ] Run status group 0 (all jobs): WRITE: bw=136MiB/s (143MB/s), 136MiB/s-136MiB/s (143MB/s-143MB/s), io=9.97GiB (10.7GB), run=75084-75084msec