# fio --ioengine=psync --filename=/dev/zvol/tank/test --size=9G --time_based --name=fio --group_reporting --runtime=600 --direct=1 --sync=1 --iodepth=1 --rw=write --bs=4k --numjobs=32
fio: (g=0): rw=write, bs=(R) 4096B-4096B, (W) 4096B-4096B, (T) 4096B-4096B, ioengine=psync, iodepth=1
...
fio-3.12
Starting 32 processes
Jobs: 32 (f=32): [W(32)][100.0%][w=181MiB/s][w=46.3k IOPS][eta 00m:00s]
fio: (groupid=0, jobs=32): err= 0: pid=95469: Fri Jan 15 12:54:59 2021
write: IOPS=66.2k, BW=258MiB/s (271MB/s)(151GiB/600002msec); 0 zone resets
clat (usec): min=59, max=143209, avg=482.78, stdev=1112.45
lat (usec): min=59, max=143210, avg=482.95, stdev=1112.45
clat percentiles (usec):
| 1.00th=[ 215], 5.00th=[ 245], 10.00th=[ 265], 20.00th=[ 293],
| 30.00th=[ 322], 40.00th=[ 359], 50.00th=[ 404], 60.00th=[ 445],
| 70.00th=[ 494], 80.00th=[ 578], 90.00th=[ 742], 95.00th=[ 996],
| 99.00th=[ 1401], 99.50th=[ 1614], 99.90th=[ 5145], 99.95th=[ 7701],
| 99.99th=[12649]
bw ( KiB/s): min= 4856, max=11424, per=3.13%, avg=8270.95, stdev=1912.80, samples=38369
iops : min= 1214, max= 2856, avg=2067.72, stdev=478.20, samples=38369
lat (usec) : 100=0.03%, 250=5.97%, 500=64.97%, 750=19.27%, 1000=4.77%
lat (msec) : 2=4.76%, 4=0.11%, 10=0.09%, 20=0.01%, 100=0.01%
lat (msec) : 250=0.01%
cpu : usr=0.45%, sys=24.12%, ctx=281344506, majf=0, minf=349
IO depths : 1=100.0%, 2=0.0%, 4=0.0%, 8=0.0%, 16=0.0%, 32=0.0%, >=64=0.0%
submit : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, 32=0.0%, 64=0.0%, >=64=0.0%
complete : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, 32=0.0%, 64=0.0%, >=64=0.0%
issued rwts: total=0,39696863,0,0 short=0,0,0,0 dropped=0,0,0,0
latency : target=0, window=0, percentile=100.00%, depth=1
Run status group 0 (all jobs):
WRITE: bw=258MiB/s (271MB/s), 258MiB/s-258MiB/s (271MB/s-271MB/s), io=151GiB (163GB), run=600002-600002msec