`fio` results for RND4K Q32T16 are ~2x higher

Linux-distro (kernel version): Kubuntu 23.10, Linux 6.5.0-14-generic
Desktop Environment (KDE/GNOME etc.): KDE
Qt Version: 5.15.10
KDiskMark Version: 3.1.3
FIO Version: fio-3.35

Description:

Title says it all 😇 Other tests results like RND4K Q1T1 or SEQ1MQ8T1 are ~same as with fio. JSON files produced by fio (jobs.read.bw and jobs.write.bw) contain the same ~2x value, so maybe KDM calculation bug?

KDM

``` KDiskMark (3.1.3): https://github.com/JonMagon/KDiskMark Flexible I/O Tester (fio-3.35): https://github.com/axboe/fio -------------------------------------------------------------------------------- * MB/s = 1,000,000 bytes/s [SATA/600 = 600,000,000 bytes/s] * KB = 1000 bytes, KiB = 1024 bytes [Read] Sequential 1 MiB (Q= 8, T= 1): 0.000 MB/s [ 0.0 IOPS] < 0.00 us> Sequential 128 KiB (Q= 32, T= 1): 0.000 MB/s [ 0.0 IOPS] < 0.00 us> Random 4 KiB (Q= 32, T=16): 477.734 MB/s [ 119434.4 IOPS] < 1071.35 us> Random 4 KiB (Q= 1, T= 1): 0.000 MB/s [ 0.0 IOPS] < 0.00 us> [Write] Sequential 1 MiB (Q= 8, T= 1): 0.000 MB/s [ 0.0 IOPS] < 0.00 us> Sequential 128 KiB (Q= 32, T= 1): 0.000 MB/s [ 0.0 IOPS] < 0.00 us> Random 4 KiB (Q= 32, T=16): 340.248 MB/s [ 85062.9 IOPS] < 1503.83 us> Random 4 KiB (Q= 1, T= 1): 0.000 MB/s [ 0.0 IOPS] < 0.00 us> Profile: Default Test: 1 GiB (x5) [Measure: 5 sec / Interval: 5 sec] Date: 2024-01-03 01:10:59 OS: ubuntu 23.10 [linux 6.5.0-14-generic] ```

fio

Read: ``` randread: (g=0): rw=randread, bs=(R) 4096B-4096B, (W) 4096B-4096B, (T) 4096B-4096B, ioengine=libaio, iodepth=32 ... fio-3.35 Starting 16 processes Jobs: 16 (f=16): [r(16)][100.0%][r=907MiB/s][r=232k IOPS][eta 00m:00s] randread: (groupid=0, jobs=16): err= 0: pid=3735: Wed Jan 3 01:08:50 2024 read: IOPS=232k, BW=905MiB/s (949MB/s)(22.1GiB/25001msec) slat (usec): min=2, max=3277, avg=68.00, stdev=92.65 clat (usec): min=142, max=6241, avg=2142.19, stdev=684.45 lat (usec): min=178, max=6332, avg=2210.18, stdev=695.64 clat percentiles (usec): | 1.00th=[ 766], 5.00th=[ 1090], 10.00th=[ 1287], 20.00th=[ 1549], | 30.00th=[ 1745], 40.00th=[ 1926], 50.00th=[ 2114], 60.00th=[ 2278], | 70.00th=[ 2474], 80.00th=[ 2704], 90.00th=[ 3064], 95.00th=[ 3326], | 99.00th=[ 3884], 99.50th=[ 4113], 99.90th=[ 4555], 99.95th=[ 4752], | 99.99th=[ 5145] bw ( KiB/s): min=887256, max=987448, per=100.00%, avg=926638.69, stdev=1252.69, samples=784 iops : min=221814, max=246862, avg=231659.67, stdev=313.17, samples=784 lat (usec) : 250=0.01%, 500=0.04%, 750=0.87%, 1000=2.47% lat (msec) : 2=40.95%, 4=54.94%, 10=0.72% cpu : usr=1.80%, sys=8.96%, ctx=5788782, majf=42, minf=848 IO depths : 1=0.1%, 2=0.1%, 4=0.1%, 8=0.1%, 16=0.1%, 32=100.0%, >=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=0.1%, 64=0.0%, >=64=0.0% issued rwts: total=5790024,0,0,0 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=905MiB/s (949MB/s), 905MiB/s-905MiB/s (949MB/s-949MB/s), io=22.1GiB (23.7GB), run=25001-25001msec Disk stats (read/write): loop0: ios=5762003/0, merge=0/0, ticks=3131037/0, in_queue=3131037, util=99.60% randwrite: (g=0): rw=randwrite, bs=(R) 4096B-4096B, (W) 4096B-4096B, (T) 4096B-4096B, ioengine=libaio, iodepth=32 ``` Write: ``` randwrite: (g=0): rw=randwrite, bs=(R) 4096B-4096B, (W) 4096B-4096B, (T) 4096B-4096B, ioengine=libaio, iodepth=32 ... fio-3.35 Starting 16 processes Jobs: 16 (f=16): [w(16)][100.0%][w=675MiB/s][w=173k IOPS][eta 00m:00s] randwrite: (groupid=0, jobs=16): err= 0: pid=3773: Wed Jan 3 01:09:19 2024 write: IOPS=173k, BW=674MiB/s (707MB/s)(16.5GiB/25004msec); 0 zone resets slat (usec): min=2, max=1819, avg=91.02, stdev=88.44 clat (usec): min=76, max=6129, avg=2872.92, stdev=542.36 lat (usec): min=101, max=6269, avg=2963.94, stdev=551.21 clat percentiles (usec): | 1.00th=[ 1696], 5.00th=[ 2024], 10.00th=[ 2212], 20.00th=[ 2409], | 30.00th=[ 2573], 40.00th=[ 2704], 50.00th=[ 2868], 60.00th=[ 2999], | 70.00th=[ 3130], 80.00th=[ 3326], 90.00th=[ 3589], 95.00th=[ 3785], | 99.00th=[ 4228], 99.50th=[ 4424], 99.90th=[ 4752], 99.95th=[ 4883], | 99.99th=[ 5211] bw ( KiB/s): min=668312, max=714360, per=100.00%, avg=690856.98, stdev=636.29, samples=784 iops : min=167078, max=178590, avg=172714.24, stdev=159.07, samples=784 lat (usec) : 100=0.01%, 250=0.01%, 500=0.01%, 750=0.01%, 1000=0.02% lat (msec) : 2=4.46%, 4=92.99%, 10=2.50% cpu : usr=2.07%, sys=7.06%, ctx=4325331, majf=0, minf=220 IO depths : 1=0.1%, 2=0.1%, 4=0.1%, 8=0.1%, 16=0.1%, 32=100.0%, >=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=0.1%, 64=0.0%, >=64=0.0% issued rwts: total=0,4316736,0,0 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): WRITE: bw=674MiB/s (707MB/s), 674MiB/s-674MiB/s (707MB/s-707MB/s), io=16.5GiB (17.7GB), run=25004-25004msec Disk stats (read/write): loop0: ios=0/4295648, merge=0/0, ticks=0/3119026, in_queue=3119044, util=99.61% ```

Steps To Reproduce:

Script below creates an in-memory XFS image /dev/shm/test.img, mounts it on /tmp/mnt/test-fs and tests with fio. When fio tests finish, script pauses, so you can do KDiskmark test on the same mount. After that, press Enter and script will unmount and delete image.

#! /usr/bin/env bash

img="/dev/shm/test.img"
dest="/tmp/mnt/test-fs"

_clean() {
  umount "$dest"
  rm -f "$img"
}

_pre_mount() {
  _clean
  mkdir -p "$dest"
  truncate -s 2G "$img"
}

_mount_xfs() {
  mkfs.xfs "$img"
  mount -o noatime "$img" "$dest"
}

_fio_test() {
  fio \
    --ioengine=libaio \
    --randrepeat=0 \
    --refill_buffers \
    --end_fsync=1 \
    --direct=1 \
    --filename="$dest/fio-test" \
    --name=$1 \
    --size=1024m \
    --runtime=25 \
    --group_reporting \
    --zero_buffers=0 \
    --rw=$1 \
    --bs=$2 \
    --iodepth=$3 \
    --numjobs=$4

  sleep 3
}

_test() {
  fio \
    --create_only=1 \
    --filename="$dest/fio-test" \
    --size=1024m \
    --zero_buffers=0 \
    --name=prepare

  _fio_test randread   4k   32  16
  _fio_test randwrite  4k   32  16

  rm -f "$dest/fio-test"
}

trap _clean EXIT

_pre_mount
_mount_xfs
_test

read -rsp "Press Enter when finished testing" < /dev/tty; echo

JonMagon / KDiskMark

`fio` results for RND4K Q32T16 are ~2x higher #137

Description:

Steps To Reproduce: