root@tools:~ # fio --name=rand --filename=/tmp/testfile --rw=randrw --bs=4k --size=1G --numjobs=4 --iodepth=32 --runtime=60 --time_based --direct=1
rand: (g=0): rw=randrw, bs=(R) 4096B-4096B, (W) 4096B-4096B, (T) 4096B-4096B, ioengine=psync, iodepth=32
...
fio-3.40
Starting 4 processes
note: both iodepth >= 1 and synchronous I/O engine are selected, queue depth will be capped at 1
note: both iodepth >= 1 and synchronous I/O engine are selected, queue depth will be capped at 1
note: both iodepth >= 1 and synchronous I/O engine are selected, queue depth will be capped at 1
note: both iodepth >= 1 and synchronous I/O engine are selected, queue depth will be capped at 1
Jobs: 4 (f=4): [m(4)][100.0%][r=12.1MiB/s,w=12.4MiB/s][r=3103,w=3184 IOPS][eta 00m:00s]
rand: (groupid=0, jobs=1): err= 0: pid=992: Wed Oct 22 10:10:55 2025
  read: IOPS=753, BW=3015KiB/s (3087kB/s)(177MiB/60001msec)
    clat (nsec): min=1644, max=31595k, avg=42007.67, stdev=205464.47
     lat (nsec): min=1712, max=31595k, avg=42188.75, stdev=205467.34
    clat percentiles (usec):
     |  1.00th=[    3],  5.00th=[    4], 10.00th=[    8], 20.00th=[   34],
     | 30.00th=[   37], 40.00th=[   38], 50.00th=[   40], 60.00th=[   41],
     | 70.00th=[   44], 80.00th=[   47], 90.00th=[   54], 95.00th=[   65],
     | 99.00th=[  102], 99.50th=[  133], 99.90th=[  635], 99.95th=[ 1270],
     | 99.99th=[ 3621]
   bw (  KiB/s): min= 2088, max= 6480, per=25.25%, avg=3017.55, stdev=469.90, samples=119
   iops        : min=  522, max= 1620, avg=754.39, stdev=117.47, samples=119
  write: IOPS=749, BW=2998KiB/s (3070kB/s)(176MiB/60001msec); 0 zone resets
    clat (usec): min=4, max=27253, avg=1288.48, stdev=400.24
     lat (usec): min=4, max=27253, avg=1288.69, stdev=400.26
    clat percentiles (usec):
     |  1.00th=[   53],  5.00th=[ 1029], 10.00th=[ 1090], 20.00th=[ 1139],
     | 30.00th=[ 1188], 40.00th=[ 1221], 50.00th=[ 1254], 60.00th=[ 1303],
     | 70.00th=[ 1352], 80.00th=[ 1418], 90.00th=[ 1549], 95.00th=[ 1696],
     | 99.00th=[ 2008], 99.50th=[ 2278], 99.90th=[ 4817], 99.95th=[ 5800],
     | 99.99th=[12780]
   bw (  KiB/s): min= 1976, max= 6840, per=25.10%, avg=2998.39, stdev=436.58, samples=119
   iops        : min=  494, max= 1710, avg=749.60, stdev=109.15, samples=119
  lat (usec)   : 2=0.01%, 4=2.52%, 10=3.06%, 20=0.23%, 50=37.76%
  lat (usec)   : 100=6.63%, 250=0.52%, 500=0.25%, 750=0.11%, 1000=1.02%
  lat (msec)   : 2=47.37%, 4=0.42%, 10=0.09%, 20=0.01%, 50=0.01%
  cpu          : usr=0.39%, sys=6.57%, ctx=57249, majf=0, minf=0
  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=45219,44973,0,0 short=0,0,0,0 dropped=0,0,0,0
     latency   : target=0, window=0, percentile=100.00%, depth=32
rand: (groupid=0, jobs=1): err= 0: pid=993: Wed Oct 22 10:10:55 2025
  read: IOPS=748, BW=2994KiB/s (3066kB/s)(175MiB/60004msec)
    clat (nsec): min=1577, max=63625k, avg=42889.33, stdev=318564.37
     lat (nsec): min=1632, max=63626k, avg=43072.26, stdev=318566.98
    clat percentiles (usec):
     |  1.00th=[    3],  5.00th=[    5], 10.00th=[    8], 20.00th=[   35],
     | 30.00th=[   37], 40.00th=[   38], 50.00th=[   40], 60.00th=[   41],
     | 70.00th=[   44], 80.00th=[   47], 90.00th=[   55], 95.00th=[   65],
     | 99.00th=[  102], 99.50th=[  133], 99.90th=[  766], 99.95th=[ 1401],
     | 99.99th=[ 3490]
   bw (  KiB/s): min= 1848, max= 7920, per=25.05%, avg=2993.61, stdev=554.39, samples=119
   iops        : min=  462, max= 1980, avg=748.40, stdev=138.60, samples=119
  write: IOPS=753, BW=3013KiB/s (3086kB/s)(177MiB/60004msec); 0 zone resets
    clat (usec): min=3, max=26199, avg=1281.35, stdev=378.13
     lat (usec): min=3, max=26199, avg=1281.56, stdev=378.16
    clat percentiles (usec):
     |  1.00th=[   41],  5.00th=[ 1020], 10.00th=[ 1090], 20.00th=[ 1139],
     | 30.00th=[ 1188], 40.00th=[ 1221], 50.00th=[ 1254], 60.00th=[ 1303],
     | 70.00th=[ 1352], 80.00th=[ 1418], 90.00th=[ 1549], 95.00th=[ 1696],
     | 99.00th=[ 2008], 99.50th=[ 2278], 99.90th=[ 4621], 99.95th=[ 5473],
     | 99.99th=[11863]
   bw (  KiB/s): min= 1976, max= 8496, per=25.22%, avg=3013.92, stdev=567.24, samples=119
   iops        : min=  494, max= 2124, avg=753.48, stdev=141.81, samples=119
  lat (usec)   : 2=0.01%, 4=2.47%, 10=2.94%, 20=0.21%, 50=38.07%
  lat (usec)   : 100=6.49%, 250=0.49%, 500=0.21%, 750=0.11%, 1000=0.98%
  lat (msec)   : 2=47.50%, 4=0.41%, 10=0.09%, 20=0.02%, 50=0.01%
  lat (msec)   : 100=0.01%
  cpu          : usr=0.40%, sys=6.56%, ctx=57377, majf=0, minf=0
  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=44917,45204,0,0 short=0,0,0,0 dropped=0,0,0,0
     latency   : target=0, window=0, percentile=100.00%, depth=32
rand: (groupid=0, jobs=1): err= 0: pid=994: Wed Oct 22 10:10:55 2025
  read: IOPS=748, BW=2993KiB/s (3065kB/s)(175MiB/60001msec)
    clat (nsec): min=1580, max=29939k, avg=41642.59, stdev=211598.81
     lat (nsec): min=1639, max=29940k, avg=41825.67, stdev=211601.70
    clat percentiles (usec):
     |  1.00th=[    3],  5.00th=[    4], 10.00th=[    7], 20.00th=[   34],
     | 30.00th=[   37], 40.00th=[   38], 50.00th=[   39], 60.00th=[   41],
     | 70.00th=[   44], 80.00th=[   47], 90.00th=[   55], 95.00th=[   65],
     | 99.00th=[   99], 99.50th=[  125], 99.90th=[  255], 99.95th=[  457],
     | 99.99th=[10552]
   bw (  KiB/s): min= 1824, max= 5192, per=25.04%, avg=2991.39, stdev=404.27, samples=119
   iops        : min=  456, max= 1298, avg=747.85, stdev=101.07, samples=119
  write: IOPS=747, BW=2989KiB/s (3060kB/s)(175MiB/60001msec); 0 zone resets
    clat (usec): min=3, max=25767, avg=1292.00, stdev=357.52
     lat (usec): min=3, max=25768, avg=1292.21, stdev=357.54
    clat percentiles (usec):
     |  1.00th=[  306],  5.00th=[ 1029], 10.00th=[ 1090], 20.00th=[ 1139],
     | 30.00th=[ 1188], 40.00th=[ 1221], 50.00th=[ 1254], 60.00th=[ 1303],
     | 70.00th=[ 1352], 80.00th=[ 1418], 90.00th=[ 1549], 95.00th=[ 1696],
     | 99.00th=[ 2008], 99.50th=[ 2311], 99.90th=[ 4752], 99.95th=[ 5407],
     | 99.99th=[11731]
   bw (  KiB/s): min= 1984, max= 5248, per=25.01%, avg=2988.77, stdev=330.12, samples=119
   iops        : min=  496, max= 1312, avg=747.19, stdev=82.53, samples=119
  lat (usec)   : 2=0.01%, 4=2.54%, 10=3.09%, 20=0.21%, 50=37.30%
  lat (usec)   : 100=6.68%, 250=0.56%, 500=0.36%, 750=0.13%, 1000=1.06%
  lat (msec)   : 2=47.53%, 4=0.45%, 10=0.08%, 20=0.02%, 50=0.01%
  cpu          : usr=0.43%, sys=6.49%, ctx=57603, majf=0, minf=0
  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=44897,44830,0,0 short=0,0,0,0 dropped=0,0,0,0
     latency   : target=0, window=0, percentile=100.00%, depth=32
rand: (groupid=0, jobs=1): err= 0: pid=995: Wed Oct 22 10:10:55 2025
  read: IOPS=736, BW=2945KiB/s (3016kB/s)(173MiB/60005msec)
    clat (nsec): min=1579, max=614980, avg=39020.91, stdev=18442.70
     lat (nsec): min=1647, max=615060, avg=39206.49, stdev=18475.75
    clat percentiles (usec):
     |  1.00th=[    3],  5.00th=[    5], 10.00th=[    8], 20.00th=[   34],
     | 30.00th=[   37], 40.00th=[   38], 50.00th=[   40], 60.00th=[   41],
     | 70.00th=[   44], 80.00th=[   47], 90.00th=[   55], 95.00th=[   64],
     | 99.00th=[   96], 99.50th=[  114], 99.90th=[  176], 99.95th=[  239],
     | 99.99th=[  392]
   bw (  KiB/s): min=   56, max= 3984, per=24.65%, avg=2945.61, stdev=427.71, samples=119
   iops        : min=   14, max=  996, avg=736.40, stdev=106.93, samples=119
  write: IOPS=736, BW=2945KiB/s (3016kB/s)(173MiB/60005msec); 0 zone resets
    clat (usec): min=339, max=28103, avg=1304.50, stdev=299.04
     lat (usec): min=340, max=28103, avg=1304.71, stdev=299.07
    clat percentiles (usec):
     |  1.00th=[  922],  5.00th=[ 1057], 10.00th=[ 1090], 20.00th=[ 1156],
     | 30.00th=[ 1188], 40.00th=[ 1221], 50.00th=[ 1254], 60.00th=[ 1303],
     | 70.00th=[ 1352], 80.00th=[ 1418], 90.00th=[ 1549], 95.00th=[ 1696],
     | 99.00th=[ 2008], 99.50th=[ 2245], 99.90th=[ 4555], 99.95th=[ 5080],
     | 99.99th=[ 6652]
   bw (  KiB/s): min=   64, max= 3336, per=24.65%, avg=2945.14, stdev=368.87, samples=119
   iops        : min=   16, max=  834, avg=736.29, stdev=92.22, samples=119
  lat (usec)   : 2=0.01%, 4=2.44%, 10=2.97%, 20=0.24%, 50=37.35%
  lat (usec)   : 100=6.60%, 250=0.37%, 500=0.06%, 750=0.10%, 1000=1.06%
  lat (msec)   : 2=48.29%, 4=0.42%, 10=0.09%, 20=0.01%, 50=0.01%
  cpu          : usr=0.34%, sys=6.51%, ctx=57300, majf=0, minf=0
  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=44180,44181,0,0 short=0,0,0,0 dropped=0,0,0,0
     latency   : target=0, window=0, percentile=100.00%, depth=32
Run status group 0 (all jobs):
   READ: bw=11.7MiB/s (12.2MB/s), 2945KiB/s-3015KiB/s (3016kB/s-3087kB/s), io=700MiB (734MB), run=60001-60005msec
  WRITE: bw=11.7MiB/s (12.2MB/s), 2945KiB/s-3013KiB/s (3016kB/s-3086kB/s), io=700MiB (734MB), run=60001-60005msec