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* [PATCH V2 0/2] nvmet: add buffered_io support for bdev-ns
@ 2022-01-28  8:51 Chaitanya Kulkarni
  2022-01-28  8:51 ` [PATCH V2 1/2] nvmet: use i_size_read() to set size for file-ns Chaitanya Kulkarni
  2022-01-28  8:51 ` [PATCH V2 2/2] nvmet: allow bdev in buffered_io mode Chaitanya Kulkarni
  0 siblings, 2 replies; 5+ messages in thread
From: Chaitanya Kulkarni @ 2022-01-28  8:51 UTC (permalink / raw)
  To: linux-nvme; +Cc: hch, kbusch, sagi, Chaitanya Kulkarni

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From: Chaitanya Kulkarni <kch@nvidia.com>

Hi,

In current implementation like NVMeOF target file backed namespace we
don't support buffered_io for block device backed namesapce. This allows
user to configure block device backend in buffered_io mode so user can
get the benefits of caching.

Please note that using this combination host needs to periodically sync
between cache and storage or set the system cache parameters
accordingly. NVMeOF target is not responsible for data consistency
between cache and storage.

fio data verification, rand read/write performance numbers :-

1. NVMeOF Target ns device_path=/dev/nvme0n1 & buffered_io=0 :-

fio Verify job :-
----------------------
  read: IOPS=27.2k, BW=106MiB/s (111MB/s)(506MiB/4762msec)
  write: IOPS=24.9k, BW=97.3MiB/s (102MB/s)(800MiB/8223msec); 0 zone resets

fio Random Write :-
----------------------
  write: IOPS=70.6k, BW=276MiB/s (289MB/s)(16.2GiB/60003msec); 0 zone resets
  write: IOPS=70.5k, BW=275MiB/s (289MB/s)(16.1GiB/60003msec); 0 zone resets
  write: IOPS=70.8k, BW=277MiB/s (290MB/s)(16.2GiB/60003msec); 0 zone resets
  write: IOPS=70.8k, BW=277MiB/s (290MB/s)(16.2GiB/60003msec); 0 zone resets
  write: IOPS=70.8k, BW=276MiB/s (290MB/s)(16.2GiB/60003msec); 0 zone resets
  write: IOPS=70.9k, BW=277MiB/s (291MB/s)(16.2GiB/60003msec); 0 zone resets
  write: IOPS=70.4k, BW=275MiB/s (288MB/s)(16.1GiB/60003msec); 0 zone resets
  write: IOPS=70.6k, BW=276MiB/s (289MB/s)(16.2GiB/60003msec); 0 zone resets
  write: IOPS=70.4k, BW=275MiB/s (288MB/s)(16.1GiB/60003msec); 0 zone resets
  write: IOPS=70.5k, BW=275MiB/s (289MB/s)(16.1GiB/60002msec); 0 zone resets

fio Random Read :- 
----------------------
  read: IOPS=70.7k, BW=276MiB/s (290MB/s)(16.2GiB/60035msec)
  read: IOPS=71.6k, BW=280MiB/s (293MB/s)(16.4GiB/60039msec)
  read: IOPS=68.4k, BW=267MiB/s (280MB/s)(15.7GiB/60037msec)
  read: IOPS=67.1k, BW=262MiB/s (275MB/s)(15.4GiB/60036msec)
  read: IOPS=72.2k, BW=282MiB/s (296MB/s)(16.5GiB/60036msec)
  read: IOPS=64.9k, BW=254MiB/s (266MB/s)(14.9GiB/60041msec)
  read: IOPS=64.9k, BW=254MiB/s (266MB/s)(14.9GiB/60041msec)
  read: IOPS=64.9k, BW=254MiB/s (266MB/s)(14.9GiB/60045msec)
  read: IOPS=69.3k, BW=271MiB/s (284MB/s)(15.9GiB/60037msec)
  read: IOPS=64.7k, BW=253MiB/s (265MB/s)(14.8GiB/60041msec)

2. NVMeOF Target ns device_path=/dev/nvme0n1 & buffered_io=1 :-

fio Verify job :-
----------------------
  read: IOPS=197k, BW=770MiB/s (808MB/s)(506MiB/657msec)
  write: IOPS=137k, BW=536MiB/s (562MB/s)(800MiB/1493msec); 0 zone resets

fio Random Write :-
----------------------
  write: IOPS=4239k, BW=16.2GiB/s (17.4GB/s)(970GiB/60002msec); 0 zone resets
  write: IOPS=4245k, BW=16.2GiB/s (17.4GB/s)(972GiB/60002msec); 0 zone resets
  write: IOPS=4202k, BW=16.0GiB/s (17.2GB/s)(962GiB/60002msec); 0 zone resets
  write: IOPS=4183k, BW=16.0GiB/s (17.1GB/s)(957GiB/60002msec); 0 zone resets
  write: IOPS=4194k, BW=16.0GiB/s (17.2GB/s)(960GiB/60002msec); 0 zone resets
  write: IOPS=4209k, BW=16.1GiB/s (17.2GB/s)(963GiB/60002msec); 0 zone resets
  write: IOPS=4164k, BW=15.9GiB/s (17.1GB/s)(953GiB/60002msec); 0 zone resets
  write: IOPS=4204k, BW=16.0GiB/s (17.2GB/s)(962GiB/60002msec); 0 zone resets
  write: IOPS=4206k, BW=16.0GiB/s (17.2GB/s)(963GiB/60002msec); 0 zone resets
  write: IOPS=4185k, BW=16.0GiB/s (17.1GB/s)(958GiB/60002msec); 0 zone resets

fio Random Read :- 
----------------------
  read: IOPS=4849k, BW=18.5GiB/s (19.9GB/s)(1110GiB/60002msec)
  read: IOPS=4951k, BW=18.9GiB/s (20.3GB/s)(1133GiB/60002msec)
  read: IOPS=5165k, BW=19.7GiB/s (21.2GB/s)(1182GiB/60001msec)
  read: IOPS=5100k, BW=19.5GiB/s (20.9GB/s)(1167GiB/60001msec)
  read: IOPS=5294k, BW=20.2GiB/s (21.7GB/s)(1212GiB/60002msec)
  read: IOPS=5044k, BW=19.2GiB/s (20.7GB/s)(1155GiB/60002msec)
  read: IOPS=5084k, BW=19.4GiB/s (20.8GB/s)(1164GiB/60002msec)
  read: IOPS=4916k, BW=18.8GiB/s (20.1GB/s)(1125GiB/60001msec)
  read: IOPS=5178k, BW=19.8GiB/s (21.2GB/s)(1185GiB/60002msec)
  read: IOPS=5027k, BW=19.2GiB/s (20.6GB/s)(1151GiB/60001msec)

-ck

changes from v1:
1. Remove first two patches and don't check for stat mode for
   block device.
2. use i_size_read() to get the size of the file.

Chaitanya Kulkarni (2):
  nvmet: use i_size_read() to set size for file-ns
  nvmet: allow bdev in buffered_io mode

 drivers/nvme/target/io-cmd-bdev.c |  3 +++
 drivers/nvme/target/io-cmd-file.c | 17 ++++-------------
 drivers/nvme/target/nvmet.h       |  2 +-
 3 files changed, 8 insertions(+), 14 deletions(-)

root@dev nvme (nvme-5.17) # ./bdev-buffered-io-test.sh 
+ NQN=testnqn
+ nvme disconnect -n testnqn
NQN:testnqn disconnected 1 controller(s)

real	0m0.334s
user	0m0.000s
sys	0m0.006s
+ for i in /sys/kernel/config/nvmet/subsystems/${NQN}/namespaces/*
+ echo 0
+ rmdir /sys/kernel/config/nvmet/subsystems/testnqn/namespaces/1
+ rm -fr /sys/kernel/config/nvmet/ports/1/subsystems/testnqn
+ rmdir /sys/kernel/config/nvmet/ports/1
+ rmdir /sys/kernel/config/nvmet/subsystems/testnqn
+ rmdir 'config/nullb/nullb*'
rmdir: failed to remove 'config/nullb/nullb*': No such file or directory
+ umount /mnt/nvme0n1
umount: /mnt/nvme0n1: no mount point specified.
+ umount /mnt/backend
umount: /mnt/backend: not mounted.
+ modprobe -r nvme_loop
+ modprobe -r nvme_fabrics
+ modprobe -r nvmet
+ modprobe -r nvme
+ modprobe -r null_blk
+ tree /sys/kernel/config
/sys/kernel/config

0 directories, 0 files
+ umount /mnt/nvme0n1
+ clear_dmesg
./compile_nvme.sh: line 3: clear_dmesg: command not found
umount: /mnt/nvme0n1: no mount point specified.
+ ./delete.sh 1
+ NQN=testnqn
+ nvme disconnect -n testnqn
Failed to disconnect by NQN: testnqn

real	0m0.001s
user	0m0.000s
sys	0m0.001s
+ for i in /sys/kernel/config/nvmet/subsystems/${NQN}/namespaces/*
+ echo 0
./delete.sh: line 9: /sys/kernel/config/nvmet/subsystems/testnqn/namespaces/*/enable: No such file or directory
+ rmdir '/sys/kernel/config/nvmet/subsystems/testnqn/namespaces/*'
rmdir: failed to remove '/sys/kernel/config/nvmet/subsystems/testnqn/namespaces/*': No such file or directory
+ rm -fr /sys/kernel/config/nvmet/ports/1/subsystems/testnqn
+ rmdir /sys/kernel/config/nvmet/ports/1
rmdir: failed to remove '/sys/kernel/config/nvmet/ports/1': No such file or directory
+ rmdir /sys/kernel/config/nvmet/subsystems/testnqn
rmdir: failed to remove '/sys/kernel/config/nvmet/subsystems/testnqn': No such file or directory
+ rmdir 'config/nullb/nullb*'
rmdir: failed to remove 'config/nullb/nullb*': No such file or directory
+ umount /mnt/nvme0n1
umount: /mnt/nvme0n1: no mount point specified.
+ umount /mnt/backend
umount: /mnt/backend: not mounted.
+ modprobe -r nvme_loop
+ modprobe -r nvme_fabrics
+ modprobe -r nvmet
+ modprobe -r nvme
+ modprobe -r null_blk
+ tree /sys/kernel/config
/sys/kernel/config

0 directories, 0 files
+ modprobe -r nvme-fabrics
+ modprobe -r nvme_loop
+ modprobe -r nvmet
+ modprobe -r nvme
+ sleep 1
+ modprobe -r nvme-core
+ lsmod
+ grep nvme
+ sleep 1
+ git diff
+ sleep 1
++ nproc
+ make -j 48 M=drivers/nvme/ modules
  CC [M]  drivers/nvme/host/core.o
  CC [M]  drivers/nvme/target/core.o
  CC [M]  drivers/nvme/target/configfs.o
  CC [M]  drivers/nvme/target/admin-cmd.o
  CC [M]  drivers/nvme/target/io-cmd-file.o
  CC [M]  drivers/nvme/target/io-cmd-bdev.o
  LD [M]  drivers/nvme/target/nvmet.o
  LD [M]  drivers/nvme/host/nvme-core.o
  MODPOST drivers/nvme/Module.symvers
  CC [M]  drivers/nvme/host/nvme-core.mod.o
  LD [M]  drivers/nvme/target/nvmet.ko
  BTF [M] drivers/nvme/target/nvmet.ko
  LD [M]  drivers/nvme/host/nvme-core.ko
  BTF [M] drivers/nvme/host/nvme-core.ko
+ HOST=drivers/nvme/host
+ TARGET=drivers/nvme/target
++ uname -r
+ HOST_DEST=/lib/modules/5.17.0-rc1nvme+/kernel/drivers/nvme/host/
++ uname -r
+ TARGET_DEST=/lib/modules/5.17.0-rc1nvme+/kernel/drivers/nvme/target/
+ cp drivers/nvme/host/nvme-core.ko drivers/nvme/host/nvme-fabrics.ko drivers/nvme/host/nvme-fc.ko drivers/nvme/host/nvme.ko drivers/nvme/host/nvme-rdma.ko drivers/nvme/host/nvme-tcp.ko /lib/modules/5.17.0-rc1nvme+/kernel/drivers/nvme/host//
+ cp drivers/nvme/target/nvme-fcloop.ko drivers/nvme/target/nvme-loop.ko drivers/nvme/target/nvmet-fc.ko drivers/nvme/target/nvmet.ko drivers/nvme/target/nvmet-rdma.ko drivers/nvme/target/nvmet-tcp.ko /lib/modules/5.17.0-rc1nvme+/kernel/drivers/nvme/target//
+ ls -lrth /lib/modules/5.17.0-rc1nvme+/kernel/drivers/nvme/host/ /lib/modules/5.17.0-rc1nvme+/kernel/drivers/nvme/target//
/lib/modules/5.17.0-rc1nvme+/kernel/drivers/nvme/host/:
total 6.7M
-rw-r--r--. 1 root root  2.8M Jan 27 17:52 nvme-core.ko
-rw-r--r--. 1 root root  448K Jan 27 17:52 nvme-fabrics.ko
-rw-r--r--. 1 root root 1015K Jan 27 17:52 nvme-fc.ko
-rw-r--r--. 1 root root  745K Jan 27 17:52 nvme.ko
-rw-r--r--. 1 root root  958K Jan 27 17:52 nvme-rdma.ko
-rw-r--r--. 1 root root  902K Jan 27 17:52 nvme-tcp.ko

/lib/modules/5.17.0-rc1nvme+/kernel/drivers/nvme/target//:
total 6.7M
-rw-r--r--. 1 root root 498K Jan 27 17:52 nvme-fcloop.ko
-rw-r--r--. 1 root root 439K Jan 27 17:52 nvme-loop.ko
-rw-r--r--. 1 root root 768K Jan 27 17:52 nvmet-fc.ko
-rw-r--r--. 1 root root 3.3M Jan 27 17:52 nvmet.ko
-rw-r--r--. 1 root root 929K Jan 27 17:52 nvmet-rdma.ko
-rw-r--r--. 1 root root 775K Jan 27 17:52 nvmet-tcp.ko
+ modprobe nvme
+ NQN=testnqn
+ nvme disconnect -n testnqn
NQN:testnqn disconnected 0 controller(s)

real	0m0.001s
user	0m0.000s
sys	0m0.001s
+ for i in /sys/kernel/config/nvmet/subsystems/${NQN}/namespaces/*
+ echo 0
./delete.sh: line 9: /sys/kernel/config/nvmet/subsystems/testnqn/namespaces/*/enable: No such file or directory
+ rmdir '/sys/kernel/config/nvmet/subsystems/testnqn/namespaces/*'
rmdir: failed to remove '/sys/kernel/config/nvmet/subsystems/testnqn/namespaces/*': No such file or directory
+ rm -fr /sys/kernel/config/nvmet/ports/1/subsystems/testnqn
+ rmdir /sys/kernel/config/nvmet/ports/1
rmdir: failed to remove '/sys/kernel/config/nvmet/ports/1': No such file or directory
+ rmdir /sys/kernel/config/nvmet/subsystems/testnqn
rmdir: failed to remove '/sys/kernel/config/nvmet/subsystems/testnqn': No such file or directory
+ rmdir 'config/nullb/nullb*'
rmdir: failed to remove 'config/nullb/nullb*': No such file or directory
+ umount /mnt/nvme0n1
umount: /mnt/nvme0n1: no mount point specified.
+ umount /mnt/backend
umount: /mnt/backend: not mounted.
+ modprobe -r nvme_loop
+ modprobe -r nvme_fabrics
+ modprobe -r nvmet
+ modprobe -r nvme
+ modprobe -r null_blk
+ tree /sys/kernel/config
/sys/kernel/config

0 directories, 0 files
+++ NN=1
+++ NQN=testnqn
+++ let NR_DEVICES=NN+1
+++ modprobe -r null_blk
+++ modprobe -r nvme
+++ modprobe null_blk nr_devices=0
+++ modprobe nvme
+++ modprobe nvme-fabrics
+++ modprobe nvmet
+++ modprobe nvme-loop
+++ dmesg -c
+++ sleep 2
+++ tree /sys/kernel/config
/sys/kernel/config
├── nullb
│   └── features
└── nvmet
    ├── hosts
    ├── ports
    └── subsystems

5 directories, 1 file
+++ mkdir /sys/kernel/config/nvmet/subsystems/testnqn
+++ mkdir /sys/kernel/config/nvmet/subsystems/testnqn/namespaces/1
+++ echo -n /dev/nvme0n1
+++ cat /sys/kernel/config/nvmet/subsystems/testnqn/namespaces/1/device_path
/dev/nvme0n1
+++ echo 1
+++ cat /sys/kernel/config/nvmet/subsystems/testnqn/namespaces/1/buffered_io
1
+++ echo 1
+++ mkdir /sys/kernel/config/nvmet/ports/1/
+++ echo -n loop
+++ echo -n 1
+++ ln -s /sys/kernel/config/nvmet/subsystems/testnqn /sys/kernel/config/nvmet/ports/1/subsystems/
+++ sleep 1
+++ echo transport=loop,nqn=testnqn
+++ sleep 1
+++ mount
+++ column -t
+++ grep nvme
+++ dmesg -c
[  659.631342] nvme nvme0: 48/0/0 default/read/poll queues
[  661.614910] nvmet: adding nsid 1 to subsystem testnqn
[  662.625653] nvmet: creating nvm controller 1 for subsystem testnqn for NQN nqn.2014-08.org.nvmexpress:uuid:8443e545-5a0b-4738-bf56-fcbf0cd13320.
[  662.625773] nvme nvme1: creating 48 I/O queues.
[  662.630443] nvme nvme1: new ctrl: "testnqn"
write-and-verify: (g=0): rw=randwrite, bs=(R) 4096B-4096B, (W) 4096B-4096B, (T) 4096B-4096B, ioengine=libaio, iodepth=4
fio-3.27
Starting 1 process
Jobs: 1 (f=1)
write-and-verify: (groupid=0, jobs=1): err= 0: pid=5346: Thu Jan 27 17:52:48 2022
  read: IOPS=197k, BW=770MiB/s (808MB/s)(506MiB/657msec)
    slat (usec): min=3, max=209, avg= 3.92, stdev= 1.39
    clat (nsec): min=1092, max=231500, avg=15464.34, stdev=4454.50
     lat (usec): min=4, max=236, avg=19.45, stdev= 5.50
    clat percentiles (nsec):
     |  1.00th=[13120],  5.00th=[13248], 10.00th=[13376], 20.00th=[13504],
     | 30.00th=[13632], 40.00th=[13760], 50.00th=[13760], 60.00th=[13888],
     | 70.00th=[14016], 80.00th=[14400], 90.00th=[24192], 95.00th=[26240],
     | 99.00th=[29312], 99.50th=[33024], 99.90th=[39680], 99.95th=[42752],
     | 99.99th=[72192]
  write: IOPS=137k, BW=536MiB/s (562MB/s)(800MiB/1493msec); 0 zone resets
    slat (usec): min=4, max=430, avg= 6.59, stdev= 2.37
    clat (nsec): min=781, max=504027, avg=22173.67, stdev=6641.70
     lat (usec): min=6, max=516, avg=28.83, stdev= 8.39
    clat percentiles (nsec):
     |  1.00th=[17536],  5.00th=[17792], 10.00th=[18048], 20.00th=[18560],
     | 30.00th=[19072], 40.00th=[19328], 50.00th=[19584], 60.00th=[20096],
     | 70.00th=[20608], 80.00th=[22656], 90.00th=[34048], 95.00th=[36608],
     | 99.00th=[43776], 99.50th=[48384], 99.90th=[56064], 99.95th=[62720],
     | 99.99th=[98816]
   bw (  KiB/s): min=510648, max=585552, per=99.53%, avg=546133.33, stdev=37606.59, samples=3
   iops        : min=127664, max=146386, avg=136533.33, stdev=9399.66, samples=3
  lat (nsec)   : 1000=0.01%
  lat (usec)   : 2=0.01%, 10=0.01%, 20=69.00%, 50=30.78%, 100=0.21%
  lat (usec)   : 250=0.01%, 500=0.01%, 750=0.01%
  cpu          : usr=27.41%, sys=32.90%, ctx=333175, majf=0, minf=3054
  IO depths    : 1=0.1%, 2=0.1%, 4=100.0%, 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=129572,204800,0,0 short=0,0,0,0 dropped=0,0,0,0
     latency   : target=0, window=0, percentile=100.00%, depth=4

Run status group 0 (all jobs):
   READ: bw=770MiB/s (808MB/s), 770MiB/s-770MiB/s (808MB/s-808MB/s), io=506MiB (531MB), run=657-657msec
  WRITE: bw=536MiB/s (562MB/s), 536MiB/s-536MiB/s (562MB/s-562MB/s), io=800MiB (839MB), run=1493-1493msec

Disk stats (read/write):
  nvme1n1: ios=0/0, merge=0/0, ticks=0/0, in_queue=0, util=0.00%
RANDREAD: (g=0): rw=randwrite, bs=(R) 4096B-4096B, (W) 4096B-4096B, (T) 4096B-4096B, ioengine=libaio, iodepth=8
...
fio-3.27
Starting 32 processes
Jobs: 32 (f=32): [w(32)][100.0%][w=16.0GiB/s][w=4204k IOPS][eta 00m:00s]
RANDREAD: (groupid=0, jobs=32): err= 0: pid=5350: Thu Jan 27 17:53:48 2022
  write: IOPS=4239k, BW=16.2GiB/s (17.4GB/s)(970GiB/60002msec); 0 zone resets
    slat (nsec): min=1052, max=6298.9k, avg=6783.36, stdev=3723.70
    clat (nsec): min=681, max=6390.7k, avg=53142.21, stdev=17451.81
     lat (usec): min=5, max=6400, avg=60.00, stdev=19.41
    clat percentiles (usec):
     |  1.00th=[   41],  5.00th=[   41], 10.00th=[   42], 20.00th=[   43],
     | 30.00th=[   43], 40.00th=[   44], 50.00th=[   47], 60.00th=[   57],
     | 70.00th=[   58], 80.00th=[   60], 90.00th=[   67], 95.00th=[   82],
     | 99.00th=[  128], 99.50th=[  139], 99.90th=[  178], 99.95th=[  202],
     | 99.99th=[  247]
   bw (  MiB/s): min=11727, max=20114, per=100.00%, avg=16575.43, stdev=79.65, samples=3808
   iops        : min=3002119, max=5149382, avg=4243308.64, stdev=20391.17, samples=3808
  lat (nsec)   : 750=0.01%, 1000=0.01%
  lat (usec)   : 2=0.01%, 4=0.01%, 10=0.01%, 20=0.01%, 50=52.95%
  lat (usec)   : 100=44.99%, 250=2.05%, 500=0.01%, 750=0.01%, 1000=0.01%
  lat (msec)   : 2=0.01%, 4=0.01%, 10=0.01%
  cpu          : usr=11.11%, sys=36.70%, ctx=254333246, majf=0, minf=458
  IO depths    : 1=0.1%, 2=0.1%, 4=0.1%, 8=100.0%, 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=0.1%, 16=0.0%, 32=0.0%, 64=0.0%, >=64=0.0%
     issued rwts: total=0,254332005,0,0 short=0,0,0,0 dropped=0,0,0,0
     latency   : target=0, window=0, percentile=100.00%, depth=8

Run status group 0 (all jobs):
  WRITE: bw=16.2GiB/s (17.4GB/s), 16.2GiB/s-16.2GiB/s (17.4GB/s-17.4GB/s), io=970GiB (1042GB), run=60002-60002msec

Disk stats (read/write):
  nvme1n1: ios=0/0, merge=0/0, ticks=0/0, in_queue=0, util=0.00%
RANDREAD: (g=0): rw=randwrite, bs=(R) 4096B-4096B, (W) 4096B-4096B, (T) 4096B-4096B, ioengine=libaio, iodepth=8
...
fio-3.27
Starting 32 processes
Jobs: 32 (f=32): [w(32)][100.0%][w=16.3GiB/s][w=4273k IOPS][eta 00m:00s]
RANDREAD: (groupid=0, jobs=32): err= 0: pid=5427: Thu Jan 27 17:54:48 2022
  write: IOPS=4245k, BW=16.2GiB/s (17.4GB/s)(972GiB/60002msec); 0 zone resets
    slat (nsec): min=1703, max=9173.2k, avg=6757.54, stdev=3629.49
    clat (nsec): min=662, max=9238.6k, avg=53063.30, stdev=15488.04
     lat (usec): min=5, max=9247, avg=59.90, stdev=17.02
    clat percentiles (usec):
     |  1.00th=[   41],  5.00th=[   42], 10.00th=[   42], 20.00th=[   43],
     | 30.00th=[   44], 40.00th=[   45], 50.00th=[   49], 60.00th=[   57],
     | 70.00th=[   59], 80.00th=[   61], 90.00th=[   65], 95.00th=[   78],
     | 99.00th=[   98], 99.50th=[  125], 99.90th=[  153], 99.95th=[  169],
     | 99.99th=[  217]
   bw (  MiB/s): min=12078, max=19996, per=100.00%, avg=16599.68, stdev=76.90, samples=3808
   iops        : min=3092171, max=5119032, avg=4249517.34, stdev=19685.78, samples=3808
  lat (nsec)   : 750=0.01%, 1000=0.01%
  lat (usec)   : 2=0.01%, 4=0.01%, 10=0.01%, 20=0.01%, 50=50.67%
  lat (usec)   : 100=48.44%, 250=0.88%, 500=0.01%, 750=0.01%, 1000=0.01%
  lat (msec)   : 2=0.01%, 4=0.01%, 10=0.01%
  cpu          : usr=11.51%, sys=36.96%, ctx=254724648, majf=0, minf=457
  IO depths    : 1=0.1%, 2=0.1%, 4=0.1%, 8=100.0%, 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=0.1%, 16=0.0%, 32=0.0%, 64=0.0%, >=64=0.0%
     issued rwts: total=0,254721978,0,0 short=0,0,0,0 dropped=0,0,0,0
     latency   : target=0, window=0, percentile=100.00%, depth=8

Run status group 0 (all jobs):
  WRITE: bw=16.2GiB/s (17.4GB/s), 16.2GiB/s-16.2GiB/s (17.4GB/s-17.4GB/s), io=972GiB (1043GB), run=60002-60002msec

Disk stats (read/write):
  nvme1n1: ios=0/0, merge=0/0, ticks=0/0, in_queue=0, util=0.00%
RANDREAD: (g=0): rw=randwrite, bs=(R) 4096B-4096B, (W) 4096B-4096B, (T) 4096B-4096B, ioengine=libaio, iodepth=8
...
fio-3.27
Starting 32 processes
Jobs: 32 (f=32): [w(32)][100.0%][w=16.3GiB/s][w=4263k IOPS][eta 00m:00s]
RANDREAD: (groupid=0, jobs=32): err= 0: pid=5463: Thu Jan 27 17:55:48 2022
  write: IOPS=4202k, BW=16.0GiB/s (17.2GB/s)(962GiB/60002msec); 0 zone resets
    slat (nsec): min=1473, max=8141.0k, avg=6835.36, stdev=4208.33
    clat (nsec): min=762, max=8205.4k, avg=53600.59, stdev=18081.09
     lat (usec): min=6, max=8214, avg=60.51, stdev=19.88
    clat percentiles (usec):
     |  1.00th=[   41],  5.00th=[   42], 10.00th=[   42], 20.00th=[   43],
     | 30.00th=[   44], 40.00th=[   45], 50.00th=[   50], 60.00th=[   57],
     | 70.00th=[   59], 80.00th=[   61], 90.00th=[   67], 95.00th=[   79],
     | 99.00th=[  118], 99.50th=[  133], 99.90th=[  163], 99.95th=[  186],
     | 99.99th=[  227]
   bw (  MiB/s): min=11930, max=19982, per=100.00%, avg=16430.36, stdev=83.37, samples=3808
   iops        : min=3054264, max=5115568, avg=4206171.98, stdev=21342.34, samples=3808
  lat (nsec)   : 1000=0.01%
  lat (usec)   : 2=0.01%, 4=0.01%, 10=0.01%, 20=0.01%, 50=50.62%
  lat (usec)   : 100=47.91%, 250=1.46%, 500=0.01%, 750=0.01%, 1000=0.01%
  lat (msec)   : 2=0.01%, 4=0.01%, 10=0.01%
  cpu          : usr=11.29%, sys=36.70%, ctx=252160334, majf=0, minf=468
  IO depths    : 1=0.1%, 2=0.1%, 4=0.1%, 8=100.0%, 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=0.1%, 16=0.0%, 32=0.0%, 64=0.0%, >=64=0.0%
     issued rwts: total=0,252156450,0,0 short=0,0,0,0 dropped=0,0,0,0
     latency   : target=0, window=0, percentile=100.00%, depth=8

Run status group 0 (all jobs):
  WRITE: bw=16.0GiB/s (17.2GB/s), 16.0GiB/s-16.0GiB/s (17.2GB/s-17.2GB/s), io=962GiB (1033GB), run=60002-60002msec

Disk stats (read/write):
  nvme1n1: ios=0/0, merge=0/0, ticks=0/0, in_queue=0, util=0.00%
RANDREAD: (g=0): rw=randwrite, bs=(R) 4096B-4096B, (W) 4096B-4096B, (T) 4096B-4096B, ioengine=libaio, iodepth=8
...
fio-3.27
Starting 32 processes
Jobs: 32 (f=32): [w(32)][100.0%][w=16.2GiB/s][w=4249k IOPS][eta 00m:00s]
RANDREAD: (groupid=0, jobs=32): err= 0: pid=5514: Thu Jan 27 17:56:49 2022
  write: IOPS=4183k, BW=16.0GiB/s (17.1GB/s)(957GiB/60002msec); 0 zone resets
    slat (nsec): min=1924, max=17060k, avg=6871.81, stdev=4168.70
    clat (nsec): min=732, max=17171k, avg=53851.87, stdev=19003.86
     lat (usec): min=6, max=17179, avg=60.80, stdev=21.03
    clat percentiles (usec):
     |  1.00th=[   41],  5.00th=[   42], 10.00th=[   42], 20.00th=[   43],
     | 30.00th=[   44], 40.00th=[   45], 50.00th=[   48], 60.00th=[   57],
     | 70.00th=[   59], 80.00th=[   61], 90.00th=[   68], 95.00th=[   84],
     | 99.00th=[  128], 99.50th=[  137], 99.90th=[  176], 99.95th=[  200],
     | 99.99th=[  239]
   bw (  MiB/s): min=11373, max=20061, per=100.00%, avg=16353.68, stdev=88.86, samples=3808
   iops        : min=2911622, max=5135864, avg=4186540.81, stdev=22748.13, samples=3808
  lat (nsec)   : 750=0.01%, 1000=0.01%
  lat (usec)   : 2=0.01%, 10=0.01%, 20=0.01%, 50=52.48%, 100=45.18%
  lat (usec)   : 250=2.33%, 500=0.01%, 750=0.01%, 1000=0.01%
  lat (msec)   : 2=0.01%, 4=0.01%, 10=0.01%, 20=0.01%
  cpu          : usr=11.24%, sys=36.38%, ctx=250990537, majf=0, minf=467
  IO depths    : 1=0.1%, 2=0.1%, 4=0.1%, 8=100.0%, 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=0.1%, 16=0.0%, 32=0.0%, 64=0.0%, >=64=0.0%
     issued rwts: total=0,250987092,0,0 short=0,0,0,0 dropped=0,0,0,0
     latency   : target=0, window=0, percentile=100.00%, depth=8

Run status group 0 (all jobs):
  WRITE: bw=16.0GiB/s (17.1GB/s), 16.0GiB/s-16.0GiB/s (17.1GB/s-17.1GB/s), io=957GiB (1028GB), run=60002-60002msec

Disk stats (read/write):
  nvme1n1: ios=0/0, merge=0/0, ticks=0/0, in_queue=0, util=0.00%
RANDREAD: (g=0): rw=randwrite, bs=(R) 4096B-4096B, (W) 4096B-4096B, (T) 4096B-4096B, ioengine=libaio, iodepth=8
...
fio-3.27
Starting 32 processes
Jobs: 32 (f=32): [w(32)][100.0%][w=14.6GiB/s][w=3828k IOPS][eta 00m:00s]
RANDREAD: (groupid=0, jobs=32): err= 0: pid=5550: Thu Jan 27 17:57:49 2022
  write: IOPS=4194k, BW=16.0GiB/s (17.2GB/s)(960GiB/60002msec); 0 zone resets
    slat (nsec): min=1322, max=28060k, avg=6843.41, stdev=4820.43
    clat (nsec): min=671, max=28139k, avg=53708.73, stdev=19454.27
     lat (usec): min=5, max=28147, avg=60.63, stdev=21.33
    clat percentiles (usec):
     |  1.00th=[   41],  5.00th=[   42], 10.00th=[   42], 20.00th=[   43],
     | 30.00th=[   44], 40.00th=[   45], 50.00th=[   49], 60.00th=[   57],
     | 70.00th=[   59], 80.00th=[   61], 90.00th=[   68], 95.00th=[   79],
     | 99.00th=[  124], 99.50th=[  137], 99.90th=[  169], 99.95th=[  188],
     | 99.99th=[  229]
   bw (  MiB/s): min=11105, max=19937, per=100.00%, avg=16409.68, stdev=84.52, samples=3808
   iops        : min=2843058, max=5103984, avg=4200878.39, stdev=21637.18, samples=3808
  lat (nsec)   : 750=0.01%, 1000=0.01%
  lat (usec)   : 2=0.01%, 10=0.01%, 20=0.01%, 50=50.82%, 100=47.64%
  lat (usec)   : 250=1.54%, 500=0.01%, 750=0.01%, 1000=0.01%
  lat (msec)   : 2=0.01%, 4=0.01%, 10=0.01%, 20=0.01%, 50=0.01%
  cpu          : usr=11.23%, sys=36.86%, ctx=251667327, majf=0, minf=462
  IO depths    : 1=0.1%, 2=0.1%, 4=0.1%, 8=100.0%, 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=0.1%, 16=0.0%, 32=0.0%, 64=0.0%, >=64=0.0%
     issued rwts: total=0,251664333,0,0 short=0,0,0,0 dropped=0,0,0,0
     latency   : target=0, window=0, percentile=100.00%, depth=8

Run status group 0 (all jobs):
  WRITE: bw=16.0GiB/s (17.2GB/s), 16.0GiB/s-16.0GiB/s (17.2GB/s-17.2GB/s), io=960GiB (1031GB), run=60002-60002msec

Disk stats (read/write):
  nvme1n1: ios=0/0, merge=0/0, ticks=0/0, in_queue=0, util=0.00%
RANDREAD: (g=0): rw=randwrite, bs=(R) 4096B-4096B, (W) 4096B-4096B, (T) 4096B-4096B, ioengine=libaio, iodepth=8
...
fio-3.27
Starting 32 processes
Jobs: 32 (f=32): [w(32)][100.0%][w=16.0GiB/s][w=4198k IOPS][eta 00m:00s]
RANDREAD: (groupid=0, jobs=32): err= 0: pid=5590: Thu Jan 27 17:58:49 2022
  write: IOPS=4209k, BW=16.1GiB/s (17.2GB/s)(963GiB/60002msec); 0 zone resets
    slat (nsec): min=1152, max=9032.6k, avg=6818.07, stdev=4518.03
    clat (nsec): min=731, max=9134.7k, avg=53517.89, stdev=19533.23
     lat (usec): min=5, max=9143, avg=60.41, stdev=21.38
    clat percentiles (usec):
     |  1.00th=[   41],  5.00th=[   42], 10.00th=[   42], 20.00th=[   43],
     | 30.00th=[   44], 40.00th=[   45], 50.00th=[   49], 60.00th=[   57],
     | 70.00th=[   59], 80.00th=[   61], 90.00th=[   67], 95.00th=[   81],
     | 99.00th=[  108], 99.50th=[  130], 99.90th=[  163], 99.95th=[  184],
     | 99.99th=[  247]
   bw (  MiB/s): min=11087, max=19994, per=100.00%, avg=16459.38, stdev=85.78, samples=3808
   iops        : min=2838462, max=5118598, avg=4213601.45, stdev=21959.20, samples=3808
  lat (nsec)   : 750=0.01%, 1000=0.01%
  lat (usec)   : 2=0.01%, 10=0.01%, 20=0.01%, 50=51.47%, 100=47.09%
  lat (usec)   : 250=1.43%, 500=0.01%, 750=0.01%, 1000=0.01%
  lat (msec)   : 2=0.01%, 4=0.01%, 10=0.01%
  cpu          : usr=11.29%, sys=36.79%, ctx=252571826, majf=0, minf=452
  IO depths    : 1=0.1%, 2=0.1%, 4=0.1%, 8=100.0%, 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=0.1%, 16=0.0%, 32=0.0%, 64=0.0%, >=64=0.0%
     issued rwts: total=0,252569484,0,0 short=0,0,0,0 dropped=0,0,0,0
     latency   : target=0, window=0, percentile=100.00%, depth=8

Run status group 0 (all jobs):
  WRITE: bw=16.1GiB/s (17.2GB/s), 16.1GiB/s-16.1GiB/s (17.2GB/s-17.2GB/s), io=963GiB (1035GB), run=60002-60002msec

Disk stats (read/write):
  nvme1n1: ios=0/0, merge=0/0, ticks=0/0, in_queue=0, util=0.00%
RANDREAD: (g=0): rw=randwrite, bs=(R) 4096B-4096B, (W) 4096B-4096B, (T) 4096B-4096B, ioengine=libaio, iodepth=8
...
fio-3.27
Starting 32 processes
Jobs: 32 (f=32): [w(32)][100.0%][w=16.3GiB/s][w=4264k IOPS][eta 00m:00s]
RANDREAD: (groupid=0, jobs=32): err= 0: pid=5656: Thu Jan 27 17:59:49 2022
  write: IOPS=4164k, BW=15.9GiB/s (17.1GB/s)(953GiB/60002msec); 0 zone resets
    slat (nsec): min=1944, max=6038.1k, avg=6904.06, stdev=4726.09
    clat (nsec): min=702, max=6151.0k, avg=54088.57, stdev=21333.47
     lat (usec): min=5, max=6160, avg=61.07, stdev=23.45
    clat percentiles (usec):
     |  1.00th=[   41],  5.00th=[   42], 10.00th=[   42], 20.00th=[   43],
     | 30.00th=[   44], 40.00th=[   45], 50.00th=[   48], 60.00th=[   57],
     | 70.00th=[   59], 80.00th=[   61], 90.00th=[   68], 95.00th=[   82],
     | 99.00th=[  129], 99.50th=[  141], 99.90th=[  182], 99.95th=[  200],
     | 99.99th=[  273]
   bw (  MiB/s): min= 9379, max=19988, per=100.00%, avg=16279.09, stdev=90.88, samples=3808
   iops        : min=2401269, max=5117100, avg=4167447.44, stdev=23265.01, samples=3808
  lat (nsec)   : 750=0.01%, 1000=0.01%
  lat (usec)   : 2=0.01%, 10=0.01%, 20=0.01%, 50=51.86%, 100=45.88%
  lat (usec)   : 250=2.25%, 500=0.01%, 750=0.01%, 1000=0.01%
  lat (msec)   : 2=0.01%, 4=0.01%, 10=0.01%
  cpu          : usr=11.46%, sys=36.02%, ctx=249868343, majf=0, minf=468
  IO depths    : 1=0.1%, 2=0.1%, 4=0.1%, 8=100.0%, 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=0.1%, 16=0.0%, 32=0.0%, 64=0.0%, >=64=0.0%
     issued rwts: total=0,249864894,0,0 short=0,0,0,0 dropped=0,0,0,0
     latency   : target=0, window=0, percentile=100.00%, depth=8

Run status group 0 (all jobs):
  WRITE: bw=15.9GiB/s (17.1GB/s), 15.9GiB/s-15.9GiB/s (17.1GB/s-17.1GB/s), io=953GiB (1023GB), run=60002-60002msec

Disk stats (read/write):
  nvme1n1: ios=0/0, merge=0/0, ticks=0/0, in_queue=0, util=0.00%
RANDREAD: (g=0): rw=randwrite, bs=(R) 4096B-4096B, (W) 4096B-4096B, (T) 4096B-4096B, ioengine=libaio, iodepth=8
...
fio-3.27
Starting 32 processes
Jobs: 32 (f=32): [w(32)][100.0%][w=16.6GiB/s][w=4344k IOPS][eta 00m:00s]
RANDREAD: (groupid=0, jobs=32): err= 0: pid=5691: Thu Jan 27 18:00:50 2022
  write: IOPS=4204k, BW=16.0GiB/s (17.2GB/s)(962GiB/60002msec); 0 zone resets
    slat (nsec): min=1793, max=4070.8k, avg=6830.69, stdev=3956.65
    clat (nsec): min=722, max=4800.9k, avg=53585.28, stdev=16879.04
     lat (usec): min=6, max=4808, avg=60.49, stdev=18.53
    clat percentiles (usec):
     |  1.00th=[   41],  5.00th=[   42], 10.00th=[   42], 20.00th=[   43],
     | 30.00th=[   44], 40.00th=[   45], 50.00th=[   50], 60.00th=[   58],
     | 70.00th=[   59], 80.00th=[   61], 90.00th=[   67], 95.00th=[   79],
     | 99.00th=[  103], 99.50th=[  128], 99.90th=[  159], 99.95th=[  178],
     | 99.99th=[  215]
   bw (  MiB/s): min=12007, max=19928, per=100.00%, avg=16435.02, stdev=78.86, samples=3808
   iops        : min=3074024, max=5101580, avg=4207364.55, stdev=20188.09, samples=3808
  lat (nsec)   : 750=0.01%, 1000=0.01%
  lat (usec)   : 2=0.01%, 10=0.01%, 20=0.01%, 50=50.36%, 100=48.55%
  lat (usec)   : 250=1.09%, 500=0.01%, 750=0.01%, 1000=0.01%
  lat (msec)   : 2=0.01%, 4=0.01%, 10=0.01%
  cpu          : usr=11.24%, sys=37.00%, ctx=252252647, majf=0, minf=459
  IO depths    : 1=0.1%, 2=0.1%, 4=0.1%, 8=100.0%, 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=0.1%, 16=0.0%, 32=0.0%, 64=0.0%, >=64=0.0%
     issued rwts: total=0,252249340,0,0 short=0,0,0,0 dropped=0,0,0,0
     latency   : target=0, window=0, percentile=100.00%, depth=8

Run status group 0 (all jobs):
  WRITE: bw=16.0GiB/s (17.2GB/s), 16.0GiB/s-16.0GiB/s (17.2GB/s-17.2GB/s), io=962GiB (1033GB), run=60002-60002msec

Disk stats (read/write):
  nvme1n1: ios=0/0, merge=0/0, ticks=0/0, in_queue=0, util=0.00%
RANDREAD: (g=0): rw=randwrite, bs=(R) 4096B-4096B, (W) 4096B-4096B, (T) 4096B-4096B, ioengine=libaio, iodepth=8
...
fio-3.27
Starting 32 processes
Jobs: 32 (f=32): [w(32)][100.0%][w=16.1GiB/s][w=4228k IOPS][eta 00m:00s]
RANDREAD: (groupid=0, jobs=32): err= 0: pid=5728: Thu Jan 27 18:01:50 2022
  write: IOPS=4206k, BW=16.0GiB/s (17.2GB/s)(963GiB/60002msec); 0 zone resets
    slat (nsec): min=1893, max=5884.2k, avg=6827.20, stdev=3323.00
    clat (nsec): min=721, max=5947.0k, avg=53554.56, stdev=15149.53
     lat (usec): min=6, max=5955, avg=60.46, stdev=16.85
    clat percentiles (usec):
     |  1.00th=[   41],  5.00th=[   42], 10.00th=[   42], 20.00th=[   43],
     | 30.00th=[   44], 40.00th=[   45], 50.00th=[   49], 60.00th=[   57],
     | 70.00th=[   59], 80.00th=[   61], 90.00th=[   66], 95.00th=[   80],
     | 99.00th=[  114], 99.50th=[  131], 99.90th=[  163], 99.95th=[  186],
     | 99.99th=[  233]
   bw (  MiB/s): min=11577, max=19959, per=100.00%, avg=16446.23, stdev=82.53, samples=3808
   iops        : min=2963773, max=5109736, avg=4210235.39, stdev=21126.75, samples=3808
  lat (nsec)   : 750=0.01%, 1000=0.01%
  lat (usec)   : 2=0.01%, 10=0.01%, 20=0.01%, 50=51.43%, 100=46.90%
  lat (usec)   : 250=1.67%, 500=0.01%, 750=0.01%, 1000=0.01%
  lat (msec)   : 2=0.01%, 4=0.01%, 10=0.01%
  cpu          : usr=11.31%, sys=36.74%, ctx=252382497, majf=0, minf=458
  IO depths    : 1=0.1%, 2=0.1%, 4=0.1%, 8=100.0%, 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=0.1%, 16=0.0%, 32=0.0%, 64=0.0%, >=64=0.0%
     issued rwts: total=0,252378162,0,0 short=0,0,0,0 dropped=0,0,0,0
     latency   : target=0, window=0, percentile=100.00%, depth=8

Run status group 0 (all jobs):
  WRITE: bw=16.0GiB/s (17.2GB/s), 16.0GiB/s-16.0GiB/s (17.2GB/s-17.2GB/s), io=963GiB (1034GB), run=60002-60002msec

Disk stats (read/write):
  nvme1n1: ios=0/0, merge=0/0, ticks=0/0, in_queue=0, util=0.00%
RANDREAD: (g=0): rw=randwrite, bs=(R) 4096B-4096B, (W) 4096B-4096B, (T) 4096B-4096B, ioengine=libaio, iodepth=8
...
fio-3.27
Starting 32 processes
Jobs: 32 (f=32): [w(32)][100.0%][w=15.2GiB/s][w=3991k IOPS][eta 00m:00s]
RANDREAD: (groupid=0, jobs=32): err= 0: pid=5764: Thu Jan 27 18:02:50 2022
  write: IOPS=4185k, BW=16.0GiB/s (17.1GB/s)(958GiB/60002msec); 0 zone resets
    slat (nsec): min=1703, max=22107k, avg=6866.93, stdev=3619.78
    clat (nsec): min=721, max=22216k, avg=53822.24, stdev=16496.57
     lat (usec): min=6, max=22225, avg=60.77, stdev=18.38
    clat percentiles (usec):
     |  1.00th=[   41],  5.00th=[   42], 10.00th=[   42], 20.00th=[   43],
     | 30.00th=[   44], 40.00th=[   45], 50.00th=[   49], 60.00th=[   58],
     | 70.00th=[   59], 80.00th=[   61], 90.00th=[   67], 95.00th=[   81],
     | 99.00th=[  126], 99.50th=[  137], 99.90th=[  167], 99.95th=[  188],
     | 99.99th=[  215]
   bw (  MiB/s): min=11586, max=20072, per=100.00%, avg=16363.86, stdev=79.91, samples=3808
   iops        : min=2966081, max=5138584, avg=4189148.29, stdev=20458.03, samples=3808
  lat (nsec)   : 750=0.01%, 1000=0.01%
  lat (usec)   : 2=0.01%, 4=0.01%, 10=0.01%, 20=0.01%, 50=51.63%
  lat (usec)   : 100=46.38%, 250=2.00%, 500=0.01%, 750=0.01%, 1000=0.01%
  lat (msec)   : 2=0.01%, 4=0.01%, 10=0.01%, 50=0.01%
  cpu          : usr=11.68%, sys=35.90%, ctx=251114127, majf=0, minf=487
  IO depths    : 1=0.1%, 2=0.1%, 4=0.1%, 8=100.0%, 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=0.1%, 16=0.0%, 32=0.0%, 64=0.0%, >=64=0.0%
     issued rwts: total=0,251110660,0,0 short=0,0,0,0 dropped=0,0,0,0
     latency   : target=0, window=0, percentile=100.00%, depth=8

Run status group 0 (all jobs):
  WRITE: bw=16.0GiB/s (17.1GB/s), 16.0GiB/s-16.0GiB/s (17.1GB/s-17.1GB/s), io=958GiB (1029GB), run=60002-60002msec

Disk stats (read/write):
  nvme1n1: ios=0/0, merge=0/0, ticks=0/0, in_queue=0, util=0.00%
RANDREAD: (g=0): rw=randread, bs=(R) 4096B-4096B, (W) 4096B-4096B, (T) 4096B-4096B, ioengine=libaio, iodepth=64
...
fio-3.27
Starting 48 processes
Jobs: 48 (f=48): [r(48)][100.0%][r=17.1GiB/s][r=4489k IOPS][eta 00m:00s]
RANDREAD: (groupid=0, jobs=48): err= 0: pid=5804: Thu Jan 27 18:03:50 2022
  read: IOPS=4849k, BW=18.5GiB/s (19.9GB/s)(1110GiB/60002msec)
    slat (nsec): min=1132, max=159145k, avg=8981.10, stdev=19376.45
    clat (nsec): min=450, max=179342k, avg=623965.09, stdev=331422.19
     lat (usec): min=5, max=179344, avg=633.04, stdev=335.77
    clat percentiles (usec):
     |  1.00th=[  400],  5.00th=[  412], 10.00th=[  420], 20.00th=[  519],
     | 30.00th=[  523], 40.00th=[  529], 50.00th=[  537], 60.00th=[  537],
     | 70.00th=[  545], 80.00th=[  570], 90.00th=[ 1123], 95.00th=[ 1172],
     | 99.00th=[ 1221], 99.50th=[ 1237], 99.90th=[ 1385], 99.95th=[ 4948],
     | 99.99th=[11469]
   bw (  MiB/s): min= 1701, max=26666, per=100.00%, avg=18969.39, stdev=72.63, samples=5712
   iops        : min=435502, max=6826592, avg=4856162.51, stdev=18593.47, samples=5712
  lat (nsec)   : 500=0.01%, 750=0.01%, 1000=0.01%
  lat (usec)   : 2=0.01%, 4=0.01%, 10=0.01%, 20=0.01%, 50=0.01%
  lat (usec)   : 100=0.01%, 250=0.01%, 500=14.96%, 750=65.56%, 1000=7.84%
  lat (msec)   : 2=11.55%, 4=0.02%, 10=0.05%, 20=0.01%, 50=0.01%
  lat (msec)   : 100=0.01%, 250=0.01%
  cpu          : usr=9.59%, sys=34.72%, ctx=290926854, majf=0, minf=3800
  IO depths    : 1=0.1%, 2=0.1%, 4=0.1%, 8=0.1%, 16=0.1%, 32=0.1%, >=64=100.0%
     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=0.1%, >=64=0.0%
     issued rwts: total=290951231,0,0,0 short=0,0,0,0 dropped=0,0,0,0
     latency   : target=0, window=0, percentile=100.00%, depth=64

Run status group 0 (all jobs):
   READ: bw=18.5GiB/s (19.9GB/s), 18.5GiB/s-18.5GiB/s (19.9GB/s-19.9GB/s), io=1110GiB (1192GB), run=60002-60002msec

Disk stats (read/write):
  nvme1n1: ios=0/0, merge=0/0, ticks=0/0, in_queue=0, util=0.00%
RANDREAD: (g=0): rw=randread, bs=(R) 4096B-4096B, (W) 4096B-4096B, (T) 4096B-4096B, ioengine=libaio, iodepth=64
...
fio-3.27
Starting 48 processes
Jobs: 48 (f=48): [r(48)][100.0%][r=17.7GiB/s][r=4652k IOPS][eta 00m:00s]
RANDREAD: (groupid=0, jobs=48): err= 0: pid=6122: Thu Jan 27 18:04:51 2022
  read: IOPS=4951k, BW=18.9GiB/s (20.3GB/s)(1133GiB/60002msec)
    slat (usec): min=2, max=14554, avg= 8.81, stdev= 5.43
    clat (nsec): min=942, max=15180k, avg=611092.58, stdev=228636.31
     lat (usec): min=5, max=15187, avg=620.00, stdev=232.12
    clat percentiles (usec):
     |  1.00th=[  400],  5.00th=[  408], 10.00th=[  416], 20.00th=[  519],
     | 30.00th=[  523], 40.00th=[  529], 50.00th=[  529], 60.00th=[  537],
     | 70.00th=[  545], 80.00th=[  553], 90.00th=[ 1123], 95.00th=[ 1172],
     | 99.00th=[ 1221], 99.50th=[ 1237], 99.90th=[ 1270], 99.95th=[ 1287],
     | 99.99th=[ 1434]
   bw (  MiB/s): min=15970, max=26850, per=100.00%, avg=19365.18, stdev=74.95, samples=5712
   iops        : min=4088368, max=6873808, avg=4957485.39, stdev=19187.62, samples=5712
  lat (nsec)   : 1000=0.01%
  lat (usec)   : 2=0.01%, 4=0.01%, 10=0.01%, 20=0.01%, 50=0.01%
  lat (usec)   : 100=0.01%, 250=0.01%, 500=15.33%, 750=66.81%, 1000=6.49%
  lat (msec)   : 2=11.36%, 4=0.01%, 10=0.01%, 20=0.01%
  cpu          : usr=9.55%, sys=35.55%, ctx=297084580, majf=0, minf=3746
  IO depths    : 1=0.1%, 2=0.1%, 4=0.1%, 8=0.1%, 16=0.1%, 32=0.1%, >=64=100.0%
     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=0.1%, >=64=0.0%
     issued rwts: total=297077529,0,0,0 short=0,0,0,0 dropped=0,0,0,0
     latency   : target=0, window=0, percentile=100.00%, depth=64

Run status group 0 (all jobs):
   READ: bw=18.9GiB/s (20.3GB/s), 18.9GiB/s-18.9GiB/s (20.3GB/s-20.3GB/s), io=1133GiB (1217GB), run=60002-60002msec

Disk stats (read/write):
  nvme1n1: ios=0/0, merge=0/0, ticks=0/0, in_queue=0, util=0.00%
RANDREAD: (g=0): rw=randread, bs=(R) 4096B-4096B, (W) 4096B-4096B, (T) 4096B-4096B, ioengine=libaio, iodepth=64
...
fio-3.27
Starting 48 processes
Jobs: 48 (f=48): [r(48)][100.0%][r=18.8GiB/s][r=4916k IOPS][eta 00m:00s]
RANDREAD: (groupid=0, jobs=48): err= 0: pid=6172: Thu Jan 27 18:05:51 2022
  read: IOPS=5165k, BW=19.7GiB/s (21.2GB/s)(1182GiB/60001msec)
    slat (usec): min=2, max=17729, avg= 8.40, stdev= 5.56
    clat (nsec): min=892, max=18656k, avg=585778.22, stdev=198124.01
     lat (usec): min=5, max=18662, avg=594.27, stdev=201.11
    clat percentiles (usec):
     |  1.00th=[  404],  5.00th=[  416], 10.00th=[  429], 20.00th=[  523],
     | 30.00th=[  529], 40.00th=[  529], 50.00th=[  537], 60.00th=[  537],
     | 70.00th=[  537], 80.00th=[  545], 90.00th=[  922], 95.00th=[ 1156],
     | 99.00th=[ 1205], 99.50th=[ 1221], 99.90th=[ 1270], 99.95th=[ 1287],
     | 99.99th=[ 1958]
   bw (  MiB/s): min=16761, max=27172, per=100.00%, avg=20200.70, stdev=70.43, samples=5712
   iops        : min=4290928, max=6956172, avg=5171378.75, stdev=18029.98, samples=5712
  lat (nsec)   : 1000=0.01%
  lat (usec)   : 2=0.01%, 4=0.01%, 10=0.01%, 20=0.01%, 50=0.01%
  lat (usec)   : 100=0.01%, 250=0.01%, 500=11.46%, 750=77.26%, 1000=2.56%
  lat (msec)   : 2=8.71%, 4=0.01%, 10=0.01%, 20=0.01%
  cpu          : usr=9.81%, sys=37.61%, ctx=309932159, majf=0, minf=3754
  IO depths    : 1=0.1%, 2=0.1%, 4=0.1%, 8=0.1%, 16=0.1%, 32=0.1%, >=64=100.0%
     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=0.1%, >=64=0.0%
     issued rwts: total=309924108,0,0,0 short=0,0,0,0 dropped=0,0,0,0
     latency   : target=0, window=0, percentile=100.00%, depth=64

Run status group 0 (all jobs):
   READ: bw=19.7GiB/s (21.2GB/s), 19.7GiB/s-19.7GiB/s (21.2GB/s-21.2GB/s), io=1182GiB (1269GB), run=60001-60001msec

Disk stats (read/write):
  nvme1n1: ios=0/0, merge=0/0, ticks=0/0, in_queue=0, util=0.00%
RANDREAD: (g=0): rw=randread, bs=(R) 4096B-4096B, (W) 4096B-4096B, (T) 4096B-4096B, ioengine=libaio, iodepth=64
...
fio-3.27
Starting 48 processes
Jobs: 48 (f=48): [r(48)][100.0%][r=18.4GiB/s][r=4823k IOPS][eta 00m:00s]
RANDREAD: (groupid=0, jobs=48): err= 0: pid=6223: Thu Jan 27 18:06:51 2022
  read: IOPS=5100k, BW=19.5GiB/s (20.9GB/s)(1167GiB/60001msec)
    slat (nsec): min=1783, max=12540k, avg=8508.96, stdev=4346.12
    clat (nsec): min=902, max=13091k, avg=593248.59, stdev=203310.48
     lat (usec): min=5, max=13098, avg=601.85, stdev=206.43
    clat percentiles (usec):
     |  1.00th=[  404],  5.00th=[  416], 10.00th=[  424], 20.00th=[  523],
     | 30.00th=[  529], 40.00th=[  529], 50.00th=[  537], 60.00th=[  537],
     | 70.00th=[  545], 80.00th=[  545], 90.00th=[  955], 95.00th=[ 1156],
     | 99.00th=[ 1205], 99.50th=[ 1221], 99.90th=[ 1254], 99.95th=[ 1270],
     | 99.99th=[ 1319]
   bw (  MiB/s): min=16307, max=26858, per=100.00%, avg=19946.86, stdev=68.81, samples=5712
   iops        : min=4174673, max=6875752, avg=5106394.77, stdev=17615.47, samples=5712
  lat (nsec)   : 1000=0.01%
  lat (usec)   : 2=0.01%, 4=0.01%, 10=0.01%, 20=0.01%, 50=0.01%
  lat (usec)   : 100=0.01%, 250=0.01%, 500=12.52%, 750=74.51%, 1000=3.63%
  lat (msec)   : 2=9.34%, 4=0.01%, 10=0.01%, 20=0.01%
  cpu          : usr=9.82%, sys=37.09%, ctx=306024761, majf=0, minf=3752
  IO depths    : 1=0.1%, 2=0.1%, 4=0.1%, 8=0.1%, 16=0.1%, 32=0.1%, >=64=100.0%
     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=0.1%, >=64=0.0%
     issued rwts: total=306018256,0,0,0 short=0,0,0,0 dropped=0,0,0,0
     latency   : target=0, window=0, percentile=100.00%, depth=64

Run status group 0 (all jobs):
   READ: bw=19.5GiB/s (20.9GB/s), 19.5GiB/s-19.5GiB/s (20.9GB/s-20.9GB/s), io=1167GiB (1253GB), run=60001-60001msec

Disk stats (read/write):
  nvme1n1: ios=0/0, merge=0/0, ticks=0/0, in_queue=0, util=0.00%
RANDREAD: (g=0): rw=randread, bs=(R) 4096B-4096B, (W) 4096B-4096B, (T) 4096B-4096B, ioengine=libaio, iodepth=64
...
fio-3.27
Starting 48 processes
Jobs: 48 (f=48): [r(48)][100.0%][r=19.4GiB/s][r=5091k IOPS][eta 00m:00s]
RANDREAD: (groupid=0, jobs=48): err= 0: pid=6296: Thu Jan 27 18:07:51 2022
  read: IOPS=5294k, BW=20.2GiB/s (21.7GB/s)(1212GiB/60002msec)
    slat (usec): min=2, max=15196, avg= 8.17, stdev= 4.41
    clat (nsec): min=882, max=22326k, avg=571595.01, stdev=165345.43
     lat (usec): min=5, max=24612, avg=579.86, stdev=167.86
    clat percentiles (usec):
     |  1.00th=[  408],  5.00th=[  424], 10.00th=[  519], 20.00th=[  529],
     | 30.00th=[  529], 40.00th=[  529], 50.00th=[  537], 60.00th=[  537],
     | 70.00th=[  537], 80.00th=[  545], 90.00th=[  553], 95.00th=[ 1123],
     | 99.00th=[ 1205], 99.50th=[ 1221], 99.90th=[ 1270], 99.95th=[ 1287],
     | 99.99th=[ 1598]
   bw (  MiB/s): min=17335, max=26843, per=100.00%, avg=20700.27, stdev=67.10, samples=5712
   iops        : min=4437902, max=6871860, avg=5299267.64, stdev=17176.46, samples=5712
  lat (nsec)   : 1000=0.01%
  lat (usec)   : 2=0.01%, 4=0.01%, 10=0.01%, 20=0.01%, 50=0.01%
  lat (usec)   : 100=0.01%, 250=0.01%, 500=7.44%, 750=84.36%, 1000=2.47%
  lat (msec)   : 2=5.72%, 4=0.01%, 10=0.01%, 20=0.01%, 50=0.01%
  cpu          : usr=9.89%, sys=38.86%, ctx=317629057, majf=0, minf=3793
  IO depths    : 1=0.1%, 2=0.1%, 4=0.1%, 8=0.1%, 16=0.1%, 32=0.1%, >=64=100.0%
     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=0.1%, >=64=0.0%
     issued rwts: total=317620780,0,0,0 short=0,0,0,0 dropped=0,0,0,0
     latency   : target=0, window=0, percentile=100.00%, depth=64

Run status group 0 (all jobs):
   READ: bw=20.2GiB/s (21.7GB/s), 20.2GiB/s-20.2GiB/s (21.7GB/s-21.7GB/s), io=1212GiB (1301GB), run=60002-60002msec

Disk stats (read/write):
  nvme1n1: ios=0/0, merge=0/0, ticks=0/0, in_queue=0, util=0.00%
RANDREAD: (g=0): rw=randread, bs=(R) 4096B-4096B, (W) 4096B-4096B, (T) 4096B-4096B, ioengine=libaio, iodepth=64
...
fio-3.27
Starting 48 processes
Jobs: 48 (f=48): [r(48)][100.0%][r=18.3GiB/s][r=4798k IOPS][eta 00m:00s]
RANDREAD: (groupid=0, jobs=48): err= 0: pid=6365: Thu Jan 27 18:08:52 2022
  read: IOPS=5044k, BW=19.2GiB/s (20.7GB/s)(1155GiB/60002msec)
    slat (usec): min=2, max=13061, avg= 8.62, stdev= 4.52
    clat (nsec): min=921, max=13609k, avg=599818.01, stdev=216963.17
     lat (usec): min=5, max=13617, avg=608.53, stdev=220.30
    clat percentiles (usec):
     |  1.00th=[  404],  5.00th=[  412], 10.00th=[  420], 20.00th=[  523],
     | 30.00th=[  529], 40.00th=[  529], 50.00th=[  537], 60.00th=[  537],
     | 70.00th=[  537], 80.00th=[  545], 90.00th=[ 1106], 95.00th=[ 1172],
     | 99.00th=[ 1221], 99.50th=[ 1237], 99.90th=[ 1270], 99.95th=[ 1287],
     | 99.99th=[ 1352]
   bw (  MiB/s): min=16173, max=26964, per=100.00%, avg=19726.76, stdev=74.27, samples=5712
   iops        : min=4140321, max=6902906, avg=5050050.54, stdev=19012.08, samples=5712
  lat (nsec)   : 1000=0.01%
  lat (usec)   : 2=0.01%, 10=0.01%, 20=0.01%, 50=0.01%, 100=0.01%
  lat (usec)   : 250=0.01%, 500=14.23%, 750=71.40%, 1000=3.68%
  lat (msec)   : 2=10.69%, 4=0.01%, 10=0.01%, 20=0.01%
  cpu          : usr=9.68%, sys=36.60%, ctx=302656317, majf=0, minf=3792
  IO depths    : 1=0.1%, 2=0.1%, 4=0.1%, 8=0.1%, 16=0.1%, 32=0.1%, >=64=100.0%
     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=0.1%, >=64=0.0%
     issued rwts: total=302651095,0,0,0 short=0,0,0,0 dropped=0,0,0,0
     latency   : target=0, window=0, percentile=100.00%, depth=64

Run status group 0 (all jobs):
   READ: bw=19.2GiB/s (20.7GB/s), 19.2GiB/s-19.2GiB/s (20.7GB/s-20.7GB/s), io=1155GiB (1240GB), run=60002-60002msec

Disk stats (read/write):
  nvme1n1: ios=0/0, merge=0/0, ticks=0/0, in_queue=0, util=0.00%
RANDREAD: (g=0): rw=randread, bs=(R) 4096B-4096B, (W) 4096B-4096B, (T) 4096B-4096B, ioengine=libaio, iodepth=64
...
fio-3.27
Starting 48 processes
Jobs: 48 (f=48): [r(48)][100.0%][r=18.4GiB/s][r=4829k IOPS][eta 00m:00s]
RANDREAD: (groupid=0, jobs=48): err= 0: pid=6415: Thu Jan 27 18:09:52 2022
  read: IOPS=5084k, BW=19.4GiB/s (20.8GB/s)(1164GiB/60002msec)
    slat (nsec): min=1833, max=13078k, avg=8547.11, stdev=4680.01
    clat (nsec): min=901, max=16594k, avg=595160.42, stdev=216066.92
     lat (usec): min=5, max=16602, avg=603.80, stdev=219.37
    clat percentiles (usec):
     |  1.00th=[  404],  5.00th=[  412], 10.00th=[  420], 20.00th=[  523],
     | 30.00th=[  529], 40.00th=[  529], 50.00th=[  529], 60.00th=[  537],
     | 70.00th=[  537], 80.00th=[  545], 90.00th=[ 1123], 95.00th=[ 1172],
     | 99.00th=[ 1221], 99.50th=[ 1237], 99.90th=[ 1270], 99.95th=[ 1287],
     | 99.99th=[ 1336]
   bw (  MiB/s): min=16019, max=27450, per=100.00%, avg=19883.77, stdev=74.22, samples=5712
   iops        : min=4100900, max=7027312, avg=5090245.61, stdev=18999.42, samples=5712
  lat (nsec)   : 1000=0.01%
  lat (usec)   : 2=0.01%, 4=0.01%, 10=0.01%, 20=0.01%, 50=0.01%
  lat (usec)   : 100=0.01%, 250=0.01%, 500=14.78%, 750=71.94%, 1000=2.25%
  lat (msec)   : 2=11.03%, 4=0.01%, 10=0.01%, 20=0.01%
  cpu          : usr=9.71%, sys=36.85%, ctx=305045338, majf=0, minf=3705
  IO depths    : 1=0.1%, 2=0.1%, 4=0.1%, 8=0.1%, 16=0.1%, 32=0.1%, >=64=100.0%
     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=0.1%, >=64=0.0%
     issued rwts: total=305037748,0,0,0 short=0,0,0,0 dropped=0,0,0,0
     latency   : target=0, window=0, percentile=100.00%, depth=64

Run status group 0 (all jobs):
   READ: bw=19.4GiB/s (20.8GB/s), 19.4GiB/s-19.4GiB/s (20.8GB/s-20.8GB/s), io=1164GiB (1249GB), run=60002-60002msec

Disk stats (read/write):
  nvme1n1: ios=0/0, merge=0/0, ticks=0/0, in_queue=0, util=0.00%
RANDREAD: (g=0): rw=randread, bs=(R) 4096B-4096B, (W) 4096B-4096B, (T) 4096B-4096B, ioengine=libaio, iodepth=64
...
fio-3.27
Starting 48 processes
Jobs: 48 (f=48): [r(48)][100.0%][r=17.8GiB/s][r=4664k IOPS][eta 00m:00s]
RANDREAD: (groupid=0, jobs=48): err= 0: pid=6466: Thu Jan 27 18:10:52 2022
  read: IOPS=4916k, BW=18.8GiB/s (20.1GB/s)(1125GiB/60001msec)
    slat (nsec): min=1934, max=13123k, avg=8874.39, stdev=4727.74
    clat (nsec): min=852, max=13751k, avg=615357.93, stdev=231967.01
     lat (usec): min=5, max=13757, avg=624.33, stdev=235.53
    clat percentiles (usec):
     |  1.00th=[  400],  5.00th=[  408], 10.00th=[  416], 20.00th=[  519],
     | 30.00th=[  529], 40.00th=[  529], 50.00th=[  529], 60.00th=[  537],
     | 70.00th=[  545], 80.00th=[  553], 90.00th=[ 1123], 95.00th=[ 1172],
     | 99.00th=[ 1221], 99.50th=[ 1237], 99.90th=[ 1270], 99.95th=[ 1287],
     | 99.99th=[ 1369]
   bw (  MiB/s): min=15963, max=26966, per=100.00%, avg=19226.37, stdev=73.18, samples=5712
   iops        : min=4086652, max=6903490, avg=4921951.14, stdev=18733.45, samples=5712
  lat (nsec)   : 1000=0.01%
  lat (usec)   : 2=0.01%, 10=0.01%, 20=0.01%, 50=0.01%, 100=0.01%
  lat (usec)   : 250=0.01%, 500=16.23%, 750=64.97%, 1000=6.63%
  lat (msec)   : 2=12.17%, 4=0.01%, 10=0.01%, 20=0.01%
  cpu          : usr=9.56%, sys=35.15%, ctx=295000587, majf=0, minf=3760
  IO depths    : 1=0.1%, 2=0.1%, 4=0.1%, 8=0.1%, 16=0.1%, 32=0.1%, >=64=100.0%
     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=0.1%, >=64=0.0%
     issued rwts: total=294994610,0,0,0 short=0,0,0,0 dropped=0,0,0,0
     latency   : target=0, window=0, percentile=100.00%, depth=64

Run status group 0 (all jobs):
   READ: bw=18.8GiB/s (20.1GB/s), 18.8GiB/s-18.8GiB/s (20.1GB/s-20.1GB/s), io=1125GiB (1208GB), run=60001-60001msec

Disk stats (read/write):
  nvme1n1: ios=0/0, merge=0/0, ticks=0/0, in_queue=0, util=0.00%
RANDREAD: (g=0): rw=randread, bs=(R) 4096B-4096B, (W) 4096B-4096B, (T) 4096B-4096B, ioengine=libaio, iodepth=64
...
fio-3.27
Starting 48 processes
Jobs: 48 (f=48): [r(48)][100.0%][r=17.7GiB/s][r=4644k IOPS][eta 00m:00s]
RANDREAD: (groupid=0, jobs=48): err= 0: pid=6527: Thu Jan 27 18:11:52 2022
  read: IOPS=5178k, BW=19.8GiB/s (21.2GB/s)(1185GiB/60002msec)
    slat (usec): min=2, max=28107, avg= 8.37, stdev= 5.52
    clat (nsec): min=852, max=31436k, avg=584283.93, stdev=204899.19
     lat (usec): min=6, max=31444, avg=592.74, stdev=208.01
    clat percentiles (usec):
     |  1.00th=[  404],  5.00th=[  416], 10.00th=[  433], 20.00th=[  523],
     | 30.00th=[  529], 40.00th=[  529], 50.00th=[  537], 60.00th=[  537],
     | 70.00th=[  545], 80.00th=[  545], 90.00th=[  873], 95.00th=[ 1156],
     | 99.00th=[ 1221], 99.50th=[ 1696], 99.90th=[ 1844], 99.95th=[ 1876],
     | 99.99th=[ 1975]
   bw (  MiB/s): min=15730, max=27345, per=100.00%, avg=20259.01, stdev=78.17, samples=5712
   iops        : min=4026896, max=7000570, avg=5186307.07, stdev=20012.58, samples=5712
  lat (nsec)   : 1000=0.01%
  lat (usec)   : 2=0.01%, 4=0.01%, 10=0.01%, 20=0.01%, 50=0.01%
  lat (usec)   : 100=0.01%, 250=0.01%, 500=10.95%, 750=78.86%, 1000=2.55%
  lat (msec)   : 2=7.63%, 4=0.01%, 10=0.01%, 20=0.01%, 50=0.01%
  cpu          : usr=9.79%, sys=37.84%, ctx=310725626, majf=0, minf=3759
  IO depths    : 1=0.1%, 2=0.1%, 4=0.1%, 8=0.1%, 16=0.1%, 32=0.1%, >=64=100.0%
     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=0.1%, >=64=0.0%
     issued rwts: total=310718002,0,0,0 short=0,0,0,0 dropped=0,0,0,0
     latency   : target=0, window=0, percentile=100.00%, depth=64

Run status group 0 (all jobs):
   READ: bw=19.8GiB/s (21.2GB/s), 19.8GiB/s-19.8GiB/s (21.2GB/s-21.2GB/s), io=1185GiB (1273GB), run=60002-60002msec

Disk stats (read/write):
  nvme1n1: ios=0/0, merge=0/0, ticks=0/0, in_queue=0, util=0.00%
RANDREAD: (g=0): rw=randread, bs=(R) 4096B-4096B, (W) 4096B-4096B, (T) 4096B-4096B, ioengine=libaio, iodepth=64
...
fio-3.27
Starting 48 processes
Jobs: 48 (f=48): [r(48)][100.0%][r=17.9GiB/s][r=4694k IOPS][eta 00m:00s]
RANDREAD: (groupid=0, jobs=48): err= 0: pid=6583: Thu Jan 27 18:12:53 2022
  read: IOPS=5027k, BW=19.2GiB/s (20.6GB/s)(1151GiB/60001msec)
    slat (usec): min=2, max=13076, avg= 8.65, stdev= 5.02
    clat (nsec): min=922, max=17165k, avg=601847.41, stdev=215517.78
     lat (usec): min=5, max=17240, avg=610.59, stdev=218.81
    clat percentiles (usec):
     |  1.00th=[  404],  5.00th=[  412], 10.00th=[  424], 20.00th=[  523],
     | 30.00th=[  529], 40.00th=[  529], 50.00th=[  537], 60.00th=[  537],
     | 70.00th=[  545], 80.00th=[  553], 90.00th=[ 1090], 95.00th=[ 1172],
     | 99.00th=[ 1221], 99.50th=[ 1237], 99.90th=[ 1287], 99.95th=[ 1303],
     | 99.99th=[ 1352]
   bw (  MiB/s): min=16418, max=26693, per=100.00%, avg=19663.30, stdev=64.58, samples=5712
   iops        : min=4203136, max=6833668, avg=5033804.61, stdev=16531.95, samples=5712
  lat (nsec)   : 1000=0.01%
  lat (usec)   : 2=0.01%, 10=0.01%, 20=0.01%, 50=0.01%, 100=0.01%
  lat (usec)   : 250=0.01%, 500=13.51%, 750=71.59%, 1000=4.67%
  lat (msec)   : 2=10.24%, 4=0.01%, 10=0.01%, 20=0.01%
  cpu          : usr=9.66%, sys=36.48%, ctx=301651235, majf=0, minf=3785
  IO depths    : 1=0.1%, 2=0.1%, 4=0.1%, 8=0.1%, 16=0.1%, 32=0.1%, >=64=100.0%
     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=0.1%, >=64=0.0%
     issued rwts: total=301643983,0,0,0 short=0,0,0,0 dropped=0,0,0,0
     latency   : target=0, window=0, percentile=100.00%, depth=64

Run status group 0 (all jobs):
   READ: bw=19.2GiB/s (20.6GB/s), 19.2GiB/s-19.2GiB/s (20.6GB/s-20.6GB/s), io=1151GiB (1236GB), run=60001-60001msec

Disk stats (read/write):
  nvme1n1: ios=0/0, merge=0/0, ticks=0/0, in_queue=0, util=0.00%
+ NQN=testnqn
+ nvme disconnect -n testnqn
NQN:testnqn disconnected 1 controller(s)

real	0m0.370s
user	0m0.000s
sys	0m0.003s
+ for i in /sys/kernel/config/nvmet/subsystems/${NQN}/namespaces/*
+ echo 0
+ rmdir /sys/kernel/config/nvmet/subsystems/testnqn/namespaces/1
+ rm -fr /sys/kernel/config/nvmet/ports/1/subsystems/testnqn
+ rmdir /sys/kernel/config/nvmet/ports/1
+ rmdir /sys/kernel/config/nvmet/subsystems/testnqn
+ rmdir 'config/nullb/nullb*'
rmdir: failed to remove 'config/nullb/nullb*': No such file or directory
+ umount /mnt/nvme0n1
umount: /mnt/nvme0n1: no mount point specified.
+ umount /mnt/backend
umount: /mnt/backend: not mounted.
+ modprobe -r nvme_loop
+ modprobe -r nvme_fabrics
+ modprobe -r nvmet
+ modprobe -r nvme
+ modprobe -r null_blk
+ tree /sys/kernel/config
/sys/kernel/config

0 directories, 0 files
+++ NN=1
+++ NQN=testnqn
+++ let NR_DEVICES=NN+1
+++ modprobe -r null_blk
+++ modprobe -r nvme
+++ modprobe null_blk nr_devices=0
+++ modprobe nvme
+++ modprobe nvme-fabrics
+++ modprobe nvmet
+++ modprobe nvme-loop
+++ dmesg -c
+++ sleep 2
+++ tree /sys/kernel/config
/sys/kernel/config
├── nullb
│   └── features
└── nvmet
    ├── hosts
    ├── ports
    └── subsystems

5 directories, 1 file
+++ mkdir /sys/kernel/config/nvmet/subsystems/testnqn
+++ mkdir /sys/kernel/config/nvmet/subsystems/testnqn/namespaces/1
+++ echo -n /dev/nvme0n1
+++ cat /sys/kernel/config/nvmet/subsystems/testnqn/namespaces/1/device_path
/dev/nvme0n1
+++ echo 0
+++ cat /sys/kernel/config/nvmet/subsystems/testnqn/namespaces/1/buffered_io
0
+++ echo 1
+++ mkdir /sys/kernel/config/nvmet/ports/1/
+++ echo -n loop
+++ echo -n 1
+++ ln -s /sys/kernel/config/nvmet/subsystems/testnqn /sys/kernel/config/nvmet/ports/1/subsystems/
+++ sleep 1
+++ echo transport=loop,nqn=testnqn
+++ sleep 1
+++ mount
+++ column -t
+++ grep nvme
+++ dmesg -c
[ 1871.786270] nvme nvme0: 48/0/0 default/read/poll queues
[ 1873.775725] nvmet: adding nsid 1 to subsystem testnqn
[ 1874.785877] nvmet: creating nvm controller 1 for subsystem testnqn for NQN nqn.2014-08.org.nvmexpress:uuid:80e5be7e-7d04-4c0b-807c-59aa6436392f.
[ 1874.786002] nvme nvme1: creating 48 I/O queues.
[ 1874.790499] nvme nvme1: new ctrl: "testnqn"
write-and-verify: (g=0): rw=randwrite, bs=(R) 4096B-4096B, (W) 4096B-4096B, (T) 4096B-4096B, ioengine=libaio, iodepth=4
fio-3.27
Starting 1 process
Jobs: 1 (f=1): [V(1)][81.2%][r=116MiB/s][r=29.8k IOPS][eta 00m:03s]                    
write-and-verify: (groupid=0, jobs=1): err= 0: pid=6693: Thu Jan 27 18:13:11 2022
  read: IOPS=27.2k, BW=106MiB/s (111MB/s)(506MiB/4762msec)
    slat (nsec): min=1032, max=516771, avg=4595.85, stdev=8646.19
    clat (usec): min=16, max=3043, avg=140.01, stdev=76.43
     lat (usec): min=45, max=3045, avg=144.74, stdev=76.35
    clat percentiles (usec):
     |  1.00th=[   62],  5.00th=[   78], 10.00th=[   93], 20.00th=[  103],
     | 30.00th=[  111], 40.00th=[  116], 50.00th=[  125], 60.00th=[  139],
     | 70.00th=[  149], 80.00th=[  169], 90.00th=[  206], 95.00th=[  221],
     | 99.00th=[  318], 99.50th=[  498], 99.90th=[  676], 99.95th=[ 1565],
     | 99.99th=[ 2868]
  write: IOPS=24.9k, BW=97.3MiB/s (102MB/s)(800MiB/8223msec); 0 zone resets
    slat (usec): min=2, max=3278, avg=12.85, stdev=20.71
    clat (usec): min=17, max=3726, avg=146.60, stdev=86.33
     lat (usec): min=58, max=3731, avg=159.59, stdev=87.97
    clat percentiles (usec):
     |  1.00th=[   82],  5.00th=[   98], 10.00th=[  104], 20.00th=[  117],
     | 30.00th=[  125], 40.00th=[  130], 50.00th=[  137], 60.00th=[  145],
     | 70.00th=[  155], 80.00th=[  165], 90.00th=[  178], 95.00th=[  202],
     | 99.00th=[  437], 99.50th=[  570], 99.90th=[  717], 99.95th=[ 2704],
     | 99.99th=[ 2966]
   bw (  KiB/s): min=41904, max=106024, per=96.74%, avg=96376.47, stdev=14628.41, samples=17
   iops        : min=10476, max=26506, avg=24094.12, stdev=3657.10, samples=17
  lat (usec)   : 20=0.01%, 50=0.12%, 100=9.84%, 250=87.51%, 500=1.80%
  lat (usec)   : 750=0.64%, 1000=0.01%
  lat (msec)   : 2=0.01%, 4=0.05%
  cpu          : usr=20.26%, sys=17.67%, ctx=112192, majf=0, minf=3053
  IO depths    : 1=0.1%, 2=0.1%, 4=100.0%, 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=129572,204800,0,0 short=0,0,0,0 dropped=0,0,0,0
     latency   : target=0, window=0, percentile=100.00%, depth=4

Run status group 0 (all jobs):
   READ: bw=106MiB/s (111MB/s), 106MiB/s-106MiB/s (111MB/s-111MB/s), io=506MiB (531MB), run=4762-4762msec
  WRITE: bw=97.3MiB/s (102MB/s), 97.3MiB/s-97.3MiB/s (102MB/s-102MB/s), io=800MiB (839MB), run=8223-8223msec

Disk stats (read/write):
  nvme1n1: ios=0/0, merge=0/0, ticks=0/0, in_queue=0, util=0.00%
RANDREAD: (g=0): rw=randwrite, bs=(R) 4096B-4096B, (W) 4096B-4096B, (T) 4096B-4096B, ioengine=libaio, iodepth=8
...
fio-3.27
Starting 32 processes
Jobs: 32 (f=32): [w(32)][100.0%][w=278MiB/s][w=71.2k IOPS][eta 00m:00s]
RANDREAD: (groupid=0, jobs=32): err= 0: pid=6701: Thu Jan 27 18:14:11 2022
  write: IOPS=70.6k, BW=276MiB/s (289MB/s)(16.2GiB/60003msec); 0 zone resets
    slat (nsec): min=1062, max=10953k, avg=8479.24, stdev=68796.36
    clat (nsec): min=782, max=21915k, avg=3616335.82, stdev=2120821.29
     lat (usec): min=52, max=21918, avg=3624.96, stdev=2118.24
    clat percentiles (usec):
     |  1.00th=[  644],  5.00th=[ 1074], 10.00th=[ 1385], 20.00th=[ 1876],
     | 30.00th=[ 2311], 40.00th=[ 2737], 50.00th=[ 3163], 60.00th=[ 3687],
     | 70.00th=[ 4293], 80.00th=[ 5080], 90.00th=[ 6390], 95.00th=[ 7701],
     | 99.00th=[10552], 99.50th=[11731], 99.90th=[14615], 99.95th=[15926],
     | 99.99th=[18744]
   bw (  KiB/s): min=227255, max=337609, per=100.00%, avg=282652.32, stdev=684.49, samples=3808
   iops        : min=56808, max=84394, avg=70657.12, stdev=171.14, samples=3808
  lat (nsec)   : 1000=0.01%
  lat (usec)   : 2=0.01%, 4=0.01%, 10=0.01%, 20=0.01%, 50=0.03%
  lat (usec)   : 100=0.02%, 250=0.02%, 500=0.35%, 750=1.27%, 1000=2.39%
  lat (msec)   : 2=18.82%, 4=42.74%, 10=33.01%, 20=1.35%, 50=0.01%
  cpu          : usr=0.61%, sys=1.37%, ctx=810168, majf=0, minf=460
  IO depths    : 1=0.1%, 2=0.1%, 4=0.1%, 8=100.0%, 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=0.1%, 16=0.0%, 32=0.0%, 64=0.0%, >=64=0.0%
     issued rwts: total=0,4235752,0,0 short=0,0,0,0 dropped=0,0,0,0
     latency   : target=0, window=0, percentile=100.00%, depth=8

Run status group 0 (all jobs):
  WRITE: bw=276MiB/s (289MB/s), 276MiB/s-276MiB/s (289MB/s-289MB/s), io=16.2GiB (17.3GB), run=60003-60003msec

Disk stats (read/write):
  nvme1n1: ios=0/0, merge=0/0, ticks=0/0, in_queue=0, util=0.00%
RANDREAD: (g=0): rw=randwrite, bs=(R) 4096B-4096B, (W) 4096B-4096B, (T) 4096B-4096B, ioengine=libaio, iodepth=8
...
fio-3.27
Starting 32 processes
Jobs: 32 (f=32): [w(32)][100.0%][w=278MiB/s][w=71.1k IOPS][eta 00m:00s]
RANDREAD: (groupid=0, jobs=32): err= 0: pid=6736: Thu Jan 27 18:15:11 2022
  write: IOPS=70.5k, BW=275MiB/s (289MB/s)(16.1GiB/60003msec); 0 zone resets
    slat (nsec): min=1032, max=18765k, avg=9164.66, stdev=78099.99
    clat (nsec): min=1132, max=28371k, avg=3619069.12, stdev=2128877.06
     lat (usec): min=58, max=28387, avg=3628.38, stdev=2126.28
    clat percentiles (usec):
     |  1.00th=[  635],  5.00th=[ 1074], 10.00th=[ 1385], 20.00th=[ 1876],
     | 30.00th=[ 2311], 40.00th=[ 2737], 50.00th=[ 3163], 60.00th=[ 3687],
     | 70.00th=[ 4293], 80.00th=[ 5080], 90.00th=[ 6390], 95.00th=[ 7701],
     | 99.00th=[10552], 99.50th=[11863], 99.90th=[14877], 99.95th=[16450],
     | 99.99th=[19268]
   bw (  KiB/s): min=220950, max=338088, per=100.00%, avg=282364.13, stdev=715.72, samples=3808
   iops        : min=55232, max=84515, avg=70584.97, stdev=178.95, samples=3808
  lat (usec)   : 2=0.01%, 4=0.01%, 10=0.01%, 20=0.01%, 50=0.03%
  lat (usec)   : 100=0.02%, 250=0.02%, 500=0.36%, 750=1.28%, 1000=2.40%
  lat (msec)   : 2=18.82%, 4=42.65%, 10=33.06%, 20=1.37%, 50=0.01%
  cpu          : usr=0.60%, sys=1.37%, ctx=814074, majf=0, minf=465
  IO depths    : 1=0.1%, 2=0.1%, 4=0.1%, 8=100.0%, 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=0.1%, 16=0.0%, 32=0.0%, 64=0.0%, >=64=0.0%
     issued rwts: total=0,4231716,0,0 short=0,0,0,0 dropped=0,0,0,0
     latency   : target=0, window=0, percentile=100.00%, depth=8

Run status group 0 (all jobs):
  WRITE: bw=275MiB/s (289MB/s), 275MiB/s-275MiB/s (289MB/s-289MB/s), io=16.1GiB (17.3GB), run=60003-60003msec

Disk stats (read/write):
  nvme1n1: ios=0/0, merge=0/0, ticks=0/0, in_queue=0, util=0.00%
RANDREAD: (g=0): rw=randwrite, bs=(R) 4096B-4096B, (W) 4096B-4096B, (T) 4096B-4096B, ioengine=libaio, iodepth=8
...
fio-3.27
Starting 32 processes
Jobs: 32 (f=32): [w(32)][100.0%][w=279MiB/s][w=71.4k IOPS][eta 00m:00s]
RANDREAD: (groupid=0, jobs=32): err= 0: pid=6874: Thu Jan 27 18:16:11 2022
  write: IOPS=70.8k, BW=277MiB/s (290MB/s)(16.2GiB/60003msec); 0 zone resets
    slat (nsec): min=1052, max=15214k, avg=8336.55, stdev=70464.37
    clat (nsec): min=933, max=27162k, avg=3603651.62, stdev=2113870.32
     lat (usec): min=53, max=27165, avg=3612.13, stdev=2111.38
    clat percentiles (usec):
     |  1.00th=[  644],  5.00th=[ 1074], 10.00th=[ 1385], 20.00th=[ 1876],
     | 30.00th=[ 2278], 40.00th=[ 2704], 50.00th=[ 3163], 60.00th=[ 3654],
     | 70.00th=[ 4293], 80.00th=[ 5080], 90.00th=[ 6390], 95.00th=[ 7635],
     | 99.00th=[10552], 99.50th=[11731], 99.90th=[14746], 99.95th=[15926],
     | 99.99th=[18744]
   bw (  KiB/s): min=221940, max=338378, per=100.00%, avg=283664.92, stdev=696.08, samples=3808
   iops        : min=55477, max=84585, avg=70909.98, stdev=174.04, samples=3808
  lat (nsec)   : 1000=0.01%
  lat (usec)   : 2=0.01%, 4=0.01%, 10=0.01%, 20=0.01%, 50=0.03%
  lat (usec)   : 100=0.02%, 250=0.02%, 500=0.35%, 750=1.28%, 1000=2.43%
  lat (msec)   : 2=18.90%, 4=42.89%, 10=32.75%, 20=1.32%, 50=0.01%
  cpu          : usr=0.60%, sys=1.37%, ctx=811420, majf=0, minf=460
  IO depths    : 1=0.1%, 2=0.1%, 4=0.1%, 8=100.0%, 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=0.1%, 16=0.0%, 32=0.0%, 64=0.0%, >=64=0.0%
     issued rwts: total=0,4250762,0,0 short=0,0,0,0 dropped=0,0,0,0
     latency   : target=0, window=0, percentile=100.00%, depth=8

Run status group 0 (all jobs):
  WRITE: bw=277MiB/s (290MB/s), 277MiB/s-277MiB/s (290MB/s-290MB/s), io=16.2GiB (17.4GB), run=60003-60003msec

Disk stats (read/write):
  nvme1n1: ios=0/0, merge=0/0, ticks=0/0, in_queue=0, util=0.00%
RANDREAD: (g=0): rw=randwrite, bs=(R) 4096B-4096B, (W) 4096B-4096B, (T) 4096B-4096B, ioengine=libaio, iodepth=8
...
fio-3.27
Starting 32 processes
Jobs: 32 (f=32): [w(32)][100.0%][w=278MiB/s][w=71.3k IOPS][eta 00m:00s]
RANDREAD: (groupid=0, jobs=32): err= 0: pid=6909: Thu Jan 27 18:17:12 2022
  write: IOPS=70.8k, BW=277MiB/s (290MB/s)(16.2GiB/60003msec); 0 zone resets
    slat (nsec): min=1042, max=14703k, avg=7972.25, stdev=65737.59
    clat (nsec): min=892, max=30708k, avg=3605587.06, stdev=2119441.89
     lat (usec): min=55, max=30714, avg=3613.70, stdev=2117.11
    clat percentiles (usec):
     |  1.00th=[  635],  5.00th=[ 1074], 10.00th=[ 1385], 20.00th=[ 1860],
     | 30.00th=[ 2278], 40.00th=[ 2704], 50.00th=[ 3163], 60.00th=[ 3654],
     | 70.00th=[ 4293], 80.00th=[ 5080], 90.00th=[ 6390], 95.00th=[ 7635],
     | 99.00th=[10552], 99.50th=[11731], 99.90th=[14746], 99.95th=[16057],
     | 99.99th=[18744]
   bw (  KiB/s): min=218037, max=337309, per=100.00%, avg=283483.15, stdev=695.32, samples=3808
   iops        : min=54507, max=84319, avg=70864.50, stdev=173.84, samples=3808
  lat (nsec)   : 1000=0.01%
  lat (usec)   : 2=0.01%, 4=0.01%, 10=0.01%, 20=0.01%, 50=0.02%
  lat (usec)   : 100=0.02%, 250=0.02%, 500=0.36%, 750=1.31%, 1000=2.43%
  lat (msec)   : 2=18.97%, 4=42.75%, 10=32.78%, 20=1.35%, 50=0.01%
  cpu          : usr=0.60%, sys=1.36%, ctx=810930, majf=0, minf=463
  IO depths    : 1=0.1%, 2=0.1%, 4=0.1%, 8=100.0%, 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=0.1%, 16=0.0%, 32=0.0%, 64=0.0%, >=64=0.0%
     issued rwts: total=0,4248890,0,0 short=0,0,0,0 dropped=0,0,0,0
     latency   : target=0, window=0, percentile=100.00%, depth=8

Run status group 0 (all jobs):
  WRITE: bw=277MiB/s (290MB/s), 277MiB/s-277MiB/s (290MB/s-290MB/s), io=16.2GiB (17.4GB), run=60003-60003msec

Disk stats (read/write):
  nvme1n1: ios=0/0, merge=0/0, ticks=0/0, in_queue=0, util=0.00%
RANDREAD: (g=0): rw=randwrite, bs=(R) 4096B-4096B, (W) 4096B-4096B, (T) 4096B-4096B, ioengine=libaio, iodepth=8
...
fio-3.27
Starting 32 processes
Jobs: 10 (f=0): [_(1),f(1),_(4),f(3),_(1),f(1),_(1),f(2),_(4),E(1),_(5),f(2),_(4),f(1),_(1)][100.0%][w=274MiB/s][w=70.1k IOPS][eta 00m:00s]
RANDREAD: (groupid=0, jobs=32): err= 0: pid=6947: Thu Jan 27 18:18:12 2022
  write: IOPS=70.8k, BW=276MiB/s (290MB/s)(16.2GiB/60003msec); 0 zone resets
    slat (nsec): min=1052, max=12322k, avg=8564.84, stdev=70836.46
    clat (nsec): min=832, max=26513k, avg=3606722.49, stdev=2118981.37
     lat (usec): min=44, max=26516, avg=3615.43, stdev=2116.31
    clat percentiles (usec):
     |  1.00th=[  644],  5.00th=[ 1057], 10.00th=[ 1385], 20.00th=[ 1860],
     | 30.00th=[ 2278], 40.00th=[ 2704], 50.00th=[ 3163], 60.00th=[ 3654],
     | 70.00th=[ 4293], 80.00th=[ 5080], 90.00th=[ 6390], 95.00th=[ 7635],
     | 99.00th=[10552], 99.50th=[11731], 99.90th=[14615], 99.95th=[15926],
     | 99.99th=[18744]
   bw (  KiB/s): min=224303, max=338155, per=100.00%, avg=283361.52, stdev=693.75, samples=3808
   iops        : min=56070, max=84529, avg=70833.75, stdev=173.45, samples=3808
  lat (nsec)   : 1000=0.01%
  lat (usec)   : 2=0.01%, 4=0.01%, 10=0.01%, 20=0.01%, 50=0.03%
  lat (usec)   : 100=0.02%, 250=0.02%, 500=0.35%, 750=1.31%, 1000=2.46%
  lat (msec)   : 2=18.95%, 4=42.66%, 10=32.86%, 20=1.34%, 50=0.01%
  cpu          : usr=0.61%, sys=1.35%, ctx=813770, majf=0, minf=444
  IO depths    : 1=0.1%, 2=0.1%, 4=0.1%, 8=100.0%, 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=0.1%, 16=0.0%, 32=0.0%, 64=0.0%, >=64=0.0%
     issued rwts: total=0,4246897,0,0 short=0,0,0,0 dropped=0,0,0,0
     latency   : target=0, window=0, percentile=100.00%, depth=8

Run status group 0 (all jobs):
  WRITE: bw=276MiB/s (290MB/s), 276MiB/s-276MiB/s (290MB/s-290MB/s), io=16.2GiB (17.4GB), run=60003-60003msec

Disk stats (read/write):
  nvme1n1: ios=0/0, merge=0/0, ticks=0/0, in_queue=0, util=0.00%
RANDREAD: (g=0): rw=randwrite, bs=(R) 4096B-4096B, (W) 4096B-4096B, (T) 4096B-4096B, ioengine=libaio, iodepth=8
...
fio-3.27
Starting 32 processes
Jobs: 32 (f=32): [w(32)][100.0%][w=283MiB/s][w=72.4k IOPS][eta 00m:00s]
RANDREAD: (groupid=0, jobs=32): err= 0: pid=6982: Thu Jan 27 18:19:12 2022
  write: IOPS=70.9k, BW=277MiB/s (291MB/s)(16.2GiB/60003msec); 0 zone resets
    slat (nsec): min=1042, max=14867k, avg=8020.33, stdev=67623.07
    clat (nsec): min=901, max=25692k, avg=3599694.38, stdev=2111664.88
     lat (usec): min=49, max=25695, avg=3607.86, stdev=2109.25
    clat percentiles (usec):
     |  1.00th=[  635],  5.00th=[ 1057], 10.00th=[ 1385], 20.00th=[ 1860],
     | 30.00th=[ 2278], 40.00th=[ 2704], 50.00th=[ 3163], 60.00th=[ 3654],
     | 70.00th=[ 4293], 80.00th=[ 5080], 90.00th=[ 6390], 95.00th=[ 7635],
     | 99.00th=[10421], 99.50th=[11731], 99.90th=[14746], 99.95th=[15926],
     | 99.99th=[18482]
   bw (  KiB/s): min=223339, max=340257, per=100.00%, avg=283985.42, stdev=696.63, samples=3808
   iops        : min=55832, max=85057, avg=70991.25, stdev=174.17, samples=3808
  lat (nsec)   : 1000=0.01%
  lat (usec)   : 2=0.01%, 4=0.01%, 10=0.01%, 20=0.01%, 50=0.02%
  lat (usec)   : 100=0.02%, 250=0.02%, 500=0.36%, 750=1.33%, 1000=2.47%
  lat (msec)   : 2=18.90%, 4=42.78%, 10=32.77%, 20=1.32%, 50=0.01%
  cpu          : usr=0.61%, sys=1.36%, ctx=812512, majf=0, minf=492
  IO depths    : 1=0.1%, 2=0.1%, 4=0.1%, 8=100.0%, 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=0.1%, 16=0.0%, 32=0.0%, 64=0.0%, >=64=0.0%
     issued rwts: total=0,4255806,0,0 short=0,0,0,0 dropped=0,0,0,0
     latency   : target=0, window=0, percentile=100.00%, depth=8

Run status group 0 (all jobs):
  WRITE: bw=277MiB/s (291MB/s), 277MiB/s-277MiB/s (291MB/s-291MB/s), io=16.2GiB (17.4GB), run=60003-60003msec

Disk stats (read/write):
  nvme1n1: ios=0/0, merge=0/0, ticks=0/0, in_queue=0, util=0.00%
RANDREAD: (g=0): rw=randwrite, bs=(R) 4096B-4096B, (W) 4096B-4096B, (T) 4096B-4096B, ioengine=libaio, iodepth=8
...
fio-3.27
Starting 32 processes
Jobs: 31 (f=0): [f(24),E(1),f(7)][100.0%][w=274MiB/s][w=70.1k IOPS][eta 00m:00s]
RANDREAD: (groupid=0, jobs=32): err= 0: pid=7018: Thu Jan 27 18:20:12 2022
  write: IOPS=70.4k, BW=275MiB/s (288MB/s)(16.1GiB/60003msec); 0 zone resets
    slat (nsec): min=1052, max=14536k, avg=8133.28, stdev=68038.63
    clat (nsec): min=821, max=27597k, avg=3626388.02, stdev=2136516.22
     lat (usec): min=62, max=27600, avg=3634.66, stdev=2134.10
    clat percentiles (usec):
     |  1.00th=[  644],  5.00th=[ 1074], 10.00th=[ 1385], 20.00th=[ 1876],
     | 30.00th=[ 2311], 40.00th=[ 2737], 50.00th=[ 3163], 60.00th=[ 3687],
     | 70.00th=[ 4293], 80.00th=[ 5145], 90.00th=[ 6456], 95.00th=[ 7701],
     | 99.00th=[10552], 99.50th=[11863], 99.90th=[14877], 99.95th=[16188],
     | 99.99th=[18744]
   bw (  KiB/s): min=208143, max=334884, per=100.00%, avg=281852.13, stdev=742.26, samples=3808
   iops        : min=52028, max=83715, avg=70457.33, stdev=185.58, samples=3808
  lat (nsec)   : 1000=0.01%
  lat (usec)   : 2=0.01%, 4=0.01%, 20=0.01%, 50=0.02%, 100=0.02%
  lat (usec)   : 250=0.02%, 500=0.35%, 750=1.29%, 1000=2.44%
  lat (msec)   : 2=18.82%, 4=42.45%, 10=33.20%, 20=1.39%, 50=0.01%
  cpu          : usr=0.61%, sys=1.33%, ctx=807486, majf=0, minf=475
  IO depths    : 1=0.1%, 2=0.1%, 4=0.1%, 8=100.0%, 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=0.1%, 16=0.0%, 32=0.0%, 64=0.0%, >=64=0.0%
     issued rwts: total=0,4224406,0,0 short=0,0,0,0 dropped=0,0,0,0
     latency   : target=0, window=0, percentile=100.00%, depth=8

Run status group 0 (all jobs):
  WRITE: bw=275MiB/s (288MB/s), 275MiB/s-275MiB/s (288MB/s-288MB/s), io=16.1GiB (17.3GB), run=60003-60003msec

Disk stats (read/write):
  nvme1n1: ios=0/0, merge=0/0, ticks=0/0, in_queue=0, util=0.00%
RANDREAD: (g=0): rw=randwrite, bs=(R) 4096B-4096B, (W) 4096B-4096B, (T) 4096B-4096B, ioengine=libaio, iodepth=8
...
fio-3.27
Starting 32 processes
Jobs: 32 (f=32): [w(32)][100.0%][w=275MiB/s][w=70.4k IOPS][eta 00m:00s]
RANDREAD: (groupid=0, jobs=32): err= 0: pid=7055: Thu Jan 27 18:21:13 2022
  write: IOPS=70.6k, BW=276MiB/s (289MB/s)(16.2GiB/60003msec); 0 zone resets
    slat (nsec): min=1032, max=20412k, avg=8158.81, stdev=69737.89
    clat (nsec): min=962, max=24941k, avg=3617807.93, stdev=2115567.18
     lat (usec): min=52, max=24943, avg=3626.11, stdev=2113.19
    clat percentiles (usec):
     |  1.00th=[  652],  5.00th=[ 1074], 10.00th=[ 1401], 20.00th=[ 1876],
     | 30.00th=[ 2311], 40.00th=[ 2737], 50.00th=[ 3163], 60.00th=[ 3687],
     | 70.00th=[ 4293], 80.00th=[ 5080], 90.00th=[ 6390], 95.00th=[ 7701],
     | 99.00th=[10552], 99.50th=[11731], 99.90th=[14746], 99.95th=[15926],
     | 99.99th=[18482]
   bw (  KiB/s): min=217283, max=336948, per=100.00%, avg=282493.76, stdev=715.13, samples=3808
   iops        : min=54314, max=84232, avg=70617.30, stdev=178.80, samples=3808
  lat (nsec)   : 1000=0.01%
  lat (usec)   : 2=0.01%, 4=0.01%, 10=0.01%, 20=0.01%, 50=0.02%
  lat (usec)   : 100=0.01%, 250=0.02%, 500=0.34%, 750=1.24%, 1000=2.37%
  lat (msec)   : 2=18.68%, 4=42.98%, 10=32.99%, 20=1.34%, 50=0.01%
  cpu          : usr=0.62%, sys=1.36%, ctx=806027, majf=0, minf=472
  IO depths    : 1=0.1%, 2=0.1%, 4=0.1%, 8=100.0%, 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=0.1%, 16=0.0%, 32=0.0%, 64=0.0%, >=64=0.0%
     issued rwts: total=0,4234361,0,0 short=0,0,0,0 dropped=0,0,0,0
     latency   : target=0, window=0, percentile=100.00%, depth=8

Run status group 0 (all jobs):
  WRITE: bw=276MiB/s (289MB/s), 276MiB/s-276MiB/s (289MB/s-289MB/s), io=16.2GiB (17.3GB), run=60003-60003msec

Disk stats (read/write):
  nvme1n1: ios=0/0, merge=0/0, ticks=0/0, in_queue=0, util=0.00%
RANDREAD: (g=0): rw=randwrite, bs=(R) 4096B-4096B, (W) 4096B-4096B, (T) 4096B-4096B, ioengine=libaio, iodepth=8
...
fio-3.27
Starting 32 processes
Jobs: 32 (f=32): [w(32)][100.0%][w=276MiB/s][w=70.7k IOPS][eta 00m:00s]
RANDREAD: (groupid=0, jobs=32): err= 0: pid=7090: Thu Jan 27 18:22:13 2022
  write: IOPS=70.4k, BW=275MiB/s (288MB/s)(16.1GiB/60003msec); 0 zone resets
    slat (nsec): min=1042, max=17861k, avg=8286.99, stdev=68542.10
    clat (nsec): min=761, max=27072k, avg=3626493.56, stdev=2113252.93
     lat (usec): min=59, max=27075, avg=3634.92, stdev=2110.79
    clat percentiles (usec):
     |  1.00th=[  652],  5.00th=[ 1090], 10.00th=[ 1401], 20.00th=[ 1893],
     | 30.00th=[ 2311], 40.00th=[ 2737], 50.00th=[ 3195], 60.00th=[ 3687],
     | 70.00th=[ 4293], 80.00th=[ 5080], 90.00th=[ 6390], 95.00th=[ 7701],
     | 99.00th=[10552], 99.50th=[11731], 99.90th=[14615], 99.95th=[15795],
     | 99.99th=[18744]
   bw (  KiB/s): min=219915, max=337142, per=100.00%, avg=281891.44, stdev=699.72, samples=3808
   iops        : min=54970, max=84277, avg=70466.40, stdev=174.95, samples=3808
  lat (nsec)   : 1000=0.01%
  lat (usec)   : 2=0.01%, 4=0.01%, 10=0.01%, 20=0.01%, 50=0.02%
  lat (usec)   : 100=0.01%, 250=0.02%, 500=0.34%, 750=1.21%, 1000=2.34%
  lat (msec)   : 2=18.55%, 4=43.04%, 10=33.13%, 20=1.34%, 50=0.01%
  cpu          : usr=0.62%, sys=1.36%, ctx=804216, majf=0, minf=431
  IO depths    : 1=0.1%, 2=0.1%, 4=0.1%, 8=100.0%, 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=0.1%, 16=0.0%, 32=0.0%, 64=0.0%, >=64=0.0%
     issued rwts: total=0,4224035,0,0 short=0,0,0,0 dropped=0,0,0,0
     latency   : target=0, window=0, percentile=100.00%, depth=8

Run status group 0 (all jobs):
  WRITE: bw=275MiB/s (288MB/s), 275MiB/s-275MiB/s (288MB/s-288MB/s), io=16.1GiB (17.3GB), run=60003-60003msec

Disk stats (read/write):
  nvme1n1: ios=0/0, merge=0/0, ticks=0/0, in_queue=0, util=0.00%
RANDREAD: (g=0): rw=randwrite, bs=(R) 4096B-4096B, (W) 4096B-4096B, (T) 4096B-4096B, ioengine=libaio, iodepth=8
...
fio-3.27
Starting 32 processes
Jobs: 32 (f=32): [w(32)][100.0%][w=271MiB/s][w=69.5k IOPS][eta 00m:00s]
RANDREAD: (groupid=0, jobs=32): err= 0: pid=7129: Thu Jan 27 18:23:13 2022
  write: IOPS=70.5k, BW=275MiB/s (289MB/s)(16.1GiB/60002msec); 0 zone resets
    slat (nsec): min=1052, max=14893k, avg=8317.42, stdev=68537.42
    clat (nsec): min=992, max=32268k, avg=3621884.28, stdev=2123143.47
     lat (usec): min=47, max=32271, avg=3630.35, stdev=2120.64
    clat percentiles (usec):
     |  1.00th=[  652],  5.00th=[ 1074], 10.00th=[ 1401], 20.00th=[ 1893],
     | 30.00th=[ 2311], 40.00th=[ 2737], 50.00th=[ 3163], 60.00th=[ 3687],
     | 70.00th=[ 4293], 80.00th=[ 5080], 90.00th=[ 6390], 95.00th=[ 7701],
     | 99.00th=[10552], 99.50th=[11863], 99.90th=[14746], 99.95th=[16188],
     | 99.99th=[18744]
   bw (  KiB/s): min=222694, max=337437, per=100.00%, avg=282249.68, stdev=701.69, samples=3808
   iops        : min=55666, max=84355, avg=70556.92, stdev=175.44, samples=3808
  lat (nsec)   : 1000=0.01%
  lat (usec)   : 2=0.01%, 4=0.01%, 10=0.01%, 20=0.01%, 50=0.02%
  lat (usec)   : 100=0.02%, 250=0.02%, 500=0.34%, 750=1.25%, 1000=2.36%
  lat (msec)   : 2=18.69%, 4=42.93%, 10=33.00%, 20=1.37%, 50=0.01%
  cpu          : usr=0.63%, sys=1.35%, ctx=806199, majf=0, minf=453
  IO depths    : 1=0.1%, 2=0.1%, 4=0.1%, 8=100.0%, 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=0.1%, 16=0.0%, 32=0.0%, 64=0.0%, >=64=0.0%
     issued rwts: total=0,4229414,0,0 short=0,0,0,0 dropped=0,0,0,0
     latency   : target=0, window=0, percentile=100.00%, depth=8

Run status group 0 (all jobs):
  WRITE: bw=275MiB/s (289MB/s), 275MiB/s-275MiB/s (289MB/s-289MB/s), io=16.1GiB (17.3GB), run=60002-60002msec

Disk stats (read/write):
  nvme1n1: ios=0/0, merge=0/0, ticks=0/0, in_queue=0, util=0.00%
RANDREAD: (g=0): rw=randread, bs=(R) 4096B-4096B, (W) 4096B-4096B, (T) 4096B-4096B, ioengine=libaio, iodepth=64
...
fio-3.27
Starting 48 processes
Jobs: 48 (f=48): [r(48)][100.0%][r=291MiB/s][r=74.6k IOPS][eta 00m:00s]
RANDREAD: (groupid=0, jobs=48): err= 0: pid=7165: Thu Jan 27 18:24:13 2022
  read: IOPS=70.7k, BW=276MiB/s (290MB/s)(16.2GiB/60035msec)
    slat (nsec): min=952, max=58117k, avg=4520.11, stdev=161503.14
    clat (usec): min=65, max=150510, avg=43420.07, stdev=10497.47
     lat (usec): min=958, max=174048, avg=43424.71, stdev=10500.87
    clat percentiles (msec):
     |  1.00th=[   25],  5.00th=[   28], 10.00th=[   30], 20.00th=[   33],
     | 30.00th=[   41], 40.00th=[   43], 50.00th=[   44], 60.00th=[   46],
     | 70.00th=[   47], 80.00th=[   51], 90.00th=[   58], 95.00th=[   62],
     | 99.00th=[   69], 99.50th=[   74], 99.90th=[   90], 99.95th=[  100],
     | 99.99th=[  118]
   bw (  KiB/s): min=211427, max=336387, per=100.00%, avg=283065.16, stdev=517.97, samples=5664
   iops        : min=52844, max=84081, avg=70748.95, stdev=129.47, samples=5664
  lat (usec)   : 100=0.01%, 250=0.01%, 500=0.01%, 750=0.01%, 1000=0.01%
  lat (msec)   : 2=0.01%, 4=0.01%, 10=0.04%, 20=0.70%, 50=78.41%
  lat (msec)   : 100=20.78%, 250=0.05%
  cpu          : usr=0.21%, sys=0.51%, ctx=207589, majf=0, minf=3775
  IO depths    : 1=0.1%, 2=0.1%, 4=0.1%, 8=0.1%, 16=0.1%, 32=0.1%, >=64=99.9%
     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=0.1%, >=64=0.0%
     issued rwts: total=4245864,0,0,0 short=0,0,0,0 dropped=0,0,0,0
     latency   : target=0, window=0, percentile=100.00%, depth=64

Run status group 0 (all jobs):
   READ: bw=276MiB/s (290MB/s), 276MiB/s-276MiB/s (290MB/s-290MB/s), io=16.2GiB (17.4GB), run=60035-60035msec

Disk stats (read/write):
  nvme1n1: ios=0/0, merge=0/0, ticks=0/0, in_queue=0, util=0.00%
RANDREAD: (g=0): rw=randread, bs=(R) 4096B-4096B, (W) 4096B-4096B, (T) 4096B-4096B, ioengine=libaio, iodepth=64
...
fio-3.27
Starting 48 processes
Jobs: 48 (f=48): [r(48)][100.0%][r=290MiB/s][r=74.4k IOPS][eta 00m:00s]
RANDREAD: (groupid=0, jobs=48): err= 0: pid=7215: Thu Jan 27 18:25:14 2022
  read: IOPS=71.6k, BW=280MiB/s (293MB/s)(16.4GiB/60039msec)
    slat (nsec): min=961, max=92120k, avg=4780.46, stdev=198912.93
    clat (usec): min=137, max=207359, avg=42871.61, stdev=10469.73
     lat (usec): min=1036, max=207361, avg=42876.49, stdev=10474.88
    clat percentiles (msec):
     |  1.00th=[   24],  5.00th=[   28], 10.00th=[   29], 20.00th=[   32],
     | 30.00th=[   40], 40.00th=[   43], 50.00th=[   44], 60.00th=[   45],
     | 70.00th=[   47], 80.00th=[   50], 90.00th=[   58], 95.00th=[   61],
     | 99.00th=[   69], 99.50th=[   73], 99.90th=[   91], 99.95th=[  103],
     | 99.99th=[  129]
   bw (  KiB/s): min=207038, max=338144, per=100.00%, avg=286710.62, stdev=517.12, samples=5664
   iops        : min=51742, max=84521, avg=71660.22, stdev=129.27, samples=5664
  lat (usec)   : 250=0.01%, 500=0.01%, 750=0.01%, 1000=0.01%
  lat (msec)   : 2=0.01%, 4=0.01%, 10=0.05%, 20=0.75%, 50=80.14%
  lat (msec)   : 100=18.99%, 250=0.05%
  cpu          : usr=0.22%, sys=0.51%, ctx=209650, majf=0, minf=3741
  IO depths    : 1=0.1%, 2=0.1%, 4=0.1%, 8=0.1%, 16=0.1%, 32=0.1%, >=64=99.9%
     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=0.1%, >=64=0.0%
     issued rwts: total=4300515,0,0,0 short=0,0,0,0 dropped=0,0,0,0
     latency   : target=0, window=0, percentile=100.00%, depth=64

Run status group 0 (all jobs):
   READ: bw=280MiB/s (293MB/s), 280MiB/s-280MiB/s (293MB/s-293MB/s), io=16.4GiB (17.6GB), run=60039-60039msec

Disk stats (read/write):
  nvme1n1: ios=0/0, merge=0/0, ticks=0/0, in_queue=0, util=0.00%
RANDREAD: (g=0): rw=randread, bs=(R) 4096B-4096B, (W) 4096B-4096B, (T) 4096B-4096B, ioengine=libaio, iodepth=64
...
fio-3.27
Starting 48 processes
Jobs: 48 (f=48): [r(48)][100.0%][r=293MiB/s][r=75.1k IOPS][eta 00m:00s]
RANDREAD: (groupid=0, jobs=48): err= 0: pid=7266: Thu Jan 27 18:26:14 2022
  read: IOPS=68.4k, BW=267MiB/s (280MB/s)(15.7GiB/60037msec)
    slat (nsec): min=961, max=94194k, avg=8621.80, stdev=342824.46
    clat (usec): min=42, max=216758, avg=44869.36, stdev=11485.17
     lat (usec): min=694, max=216762, avg=44878.09, stdev=11505.95
    clat percentiles (msec):
     |  1.00th=[   22],  5.00th=[   28], 10.00th=[   30], 20.00th=[   34],
     | 30.00th=[   42], 40.00th=[   44], 50.00th=[   45], 60.00th=[   47],
     | 70.00th=[   49], 80.00th=[   54], 90.00th=[   60], 95.00th=[   63],
     | 99.00th=[   77], 99.50th=[   88], 99.90th=[  107], 99.95th=[  113],
     | 99.99th=[  138]
   bw (  KiB/s): min=184285, max=333915, per=100.00%, avg=273874.23, stdev=543.14, samples=5664
   iops        : min=46054, max=83457, avg=68452.00, stdev=135.77, samples=5664
  lat (usec)   : 50=0.01%, 100=0.01%, 250=0.01%, 500=0.01%, 750=0.01%
  lat (usec)   : 1000=0.01%
  lat (msec)   : 2=0.01%, 4=0.01%, 10=0.10%, 20=0.83%, 50=73.84%
  lat (msec)   : 100=25.03%, 250=0.19%
  cpu          : usr=0.22%, sys=0.50%, ctx=206236, majf=0, minf=3699
  IO depths    : 1=0.1%, 2=0.1%, 4=0.1%, 8=0.1%, 16=0.1%, 32=0.1%, >=64=99.9%
     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=0.1%, >=64=0.0%
     issued rwts: total=4108428,0,0,0 short=0,0,0,0 dropped=0,0,0,0
     latency   : target=0, window=0, percentile=100.00%, depth=64

Run status group 0 (all jobs):
   READ: bw=267MiB/s (280MB/s), 267MiB/s-267MiB/s (280MB/s-280MB/s), io=15.7GiB (16.8GB), run=60037-60037msec

Disk stats (read/write):
  nvme1n1: ios=0/0, merge=0/0, ticks=0/0, in_queue=0, util=0.00%
RANDREAD: (g=0): rw=randread, bs=(R) 4096B-4096B, (W) 4096B-4096B, (T) 4096B-4096B, ioengine=libaio, iodepth=64
...
fio-3.27
Starting 48 processes
Jobs: 48 (f=48): [r(48)][100.0%][r=290MiB/s][r=74.3k IOPS][eta 00m:00s]
RANDREAD: (groupid=0, jobs=48): err= 0: pid=7316: Thu Jan 27 18:27:14 2022
  read: IOPS=67.1k, BW=262MiB/s (275MB/s)(15.4GiB/60036msec)
    slat (nsec): min=951, max=55729k, avg=4035.52, stdev=113426.11
    clat (usec): min=210, max=124444, avg=45794.93, stdev=10681.33
     lat (usec): min=569, max=160416, avg=45799.08, stdev=10682.15
    clat percentiles (msec):
     |  1.00th=[   26],  5.00th=[   29], 10.00th=[   31], 20.00th=[   38],
     | 30.00th=[   43], 40.00th=[   44], 50.00th=[   46], 60.00th=[   47],
     | 70.00th=[   50], 80.00th=[   56], 90.00th=[   61], 95.00th=[   64],
     | 99.00th=[   72], 99.50th=[   77], 99.90th=[   86], 99.95th=[   92],
     | 99.99th=[  105]
   bw (  KiB/s): min=215248, max=327081, per=100.00%, avg=268405.62, stdev=452.79, samples=5664
   iops        : min=53792, max=81752, avg=67085.35, stdev=113.19, samples=5664
  lat (usec)   : 250=0.01%, 500=0.01%, 750=0.01%, 1000=0.01%
  lat (msec)   : 2=0.01%, 4=0.01%, 10=0.04%, 20=0.48%, 50=70.86%
  lat (msec)   : 100=28.60%, 250=0.02%
  cpu          : usr=0.21%, sys=0.48%, ctx=205998, majf=0, minf=3682
  IO depths    : 1=0.1%, 2=0.1%, 4=0.1%, 8=0.1%, 16=0.1%, 32=0.1%, >=64=99.9%
     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=0.1%, >=64=0.0%
     issued rwts: total=4026005,0,0,0 short=0,0,0,0 dropped=0,0,0,0
     latency   : target=0, window=0, percentile=100.00%, depth=64

Run status group 0 (all jobs):
   READ: bw=262MiB/s (275MB/s), 262MiB/s-262MiB/s (275MB/s-275MB/s), io=15.4GiB (16.5GB), run=60036-60036msec

Disk stats (read/write):
  nvme1n1: ios=0/0, merge=0/0, ticks=0/0, in_queue=0, util=0.00%
RANDREAD: (g=0): rw=randread, bs=(R) 4096B-4096B, (W) 4096B-4096B, (T) 4096B-4096B, ioengine=libaio, iodepth=64
...
fio-3.27
Starting 48 processes
Jobs: 48 (f=48): [r(48)][100.0%][r=293MiB/s][r=75.1k IOPS][eta 00m:00s]
RANDREAD: (groupid=0, jobs=48): err= 0: pid=7369: Thu Jan 27 18:28:15 2022
  read: IOPS=72.2k, BW=282MiB/s (296MB/s)(16.5GiB/60036msec)
    slat (nsec): min=951, max=130905k, avg=13129.16, stdev=481989.11
    clat (usec): min=39, max=213166, avg=42523.90, stdev=11610.80
     lat (usec): min=112, max=213169, avg=42537.15, stdev=11642.39
    clat percentiles (msec):
     |  1.00th=[   15],  5.00th=[   28], 10.00th=[   29], 20.00th=[   32],
     | 30.00th=[   39], 40.00th=[   42], 50.00th=[   44], 60.00th=[   45],
     | 70.00th=[   47], 80.00th=[   50], 90.00th=[   58], 95.00th=[   62],
     | 99.00th=[   78], 99.50th=[   85], 99.90th=[  101], 99.95th=[  110],
     | 99.99th=[  140]
   bw (  KiB/s): min=186271, max=362505, per=100.00%, avg=289027.55, stdev=639.85, samples=5664
   iops        : min=46554, max=90618, avg=72239.86, stdev=159.96, samples=5664
  lat (usec)   : 50=0.01%, 100=0.01%, 250=0.01%, 500=0.01%, 750=0.01%
  lat (usec)   : 1000=0.01%
  lat (msec)   : 2=0.01%, 4=0.03%, 10=0.19%, 20=1.48%, 50=79.68%
  lat (msec)   : 100=18.52%, 250=0.10%
  cpu          : usr=0.23%, sys=0.51%, ctx=209830, majf=0, minf=3679
  IO depths    : 1=0.1%, 2=0.1%, 4=0.1%, 8=0.1%, 16=0.1%, 32=0.1%, >=64=99.9%
     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=0.1%, >=64=0.0%
     issued rwts: total=4334765,0,0,0 short=0,0,0,0 dropped=0,0,0,0
     latency   : target=0, window=0, percentile=100.00%, depth=64

Run status group 0 (all jobs):
   READ: bw=282MiB/s (296MB/s), 282MiB/s-282MiB/s (296MB/s-296MB/s), io=16.5GiB (17.8GB), run=60036-60036msec

Disk stats (read/write):
  nvme1n1: ios=0/0, merge=0/0, ticks=0/0, in_queue=0, util=0.00%
RANDREAD: (g=0): rw=randread, bs=(R) 4096B-4096B, (W) 4096B-4096B, (T) 4096B-4096B, ioengine=libaio, iodepth=64
...
fio-3.27
Starting 48 processes
Jobs: 48 (f=48): [r(48)][100.0%][r=252MiB/s][r=64.5k IOPS][eta 00m:00s]
RANDREAD: (groupid=0, jobs=48): err= 0: pid=7420: Thu Jan 27 18:29:15 2022
  read: IOPS=64.9k, BW=254MiB/s (266MB/s)(14.9GiB/60041msec)
    slat (nsec): min=962, max=140336k, avg=8685.85, stdev=361027.29
    clat (usec): min=22, max=236662, avg=47307.13, stdev=11546.15
     lat (usec): min=158, max=236664, avg=47315.97, stdev=11566.36
    clat percentiles (msec):
     |  1.00th=[   25],  5.00th=[   29], 10.00th=[   32], 20.00th=[   41],
     | 30.00th=[   44], 40.00th=[   45], 50.00th=[   47], 60.00th=[   48],
     | 70.00th=[   52], 80.00th=[   58], 90.00th=[   62], 95.00th=[   65],
     | 99.00th=[   79], 99.50th=[   89], 99.90th=[  109], 99.95th=[  115],
     | 99.99th=[  138]
   bw (  KiB/s): min=184485, max=305435, per=100.00%, avg=259804.55, stdev=387.19, samples=5664
   iops        : min=46101, max=76340, avg=64934.75, stdev=96.82, samples=5664
  lat (usec)   : 50=0.01%, 100=0.01%, 250=0.01%, 500=0.01%, 750=0.01%
  lat (usec)   : 1000=0.01%
  lat (msec)   : 2=0.01%, 4=0.02%, 10=0.10%, 20=0.61%, 50=66.06%
  lat (msec)   : 100=32.99%, 250=0.22%
  cpu          : usr=0.22%, sys=0.47%, ctx=204069, majf=0, minf=3728
  IO depths    : 1=0.1%, 2=0.1%, 4=0.1%, 8=0.1%, 16=0.1%, 32=0.1%, >=64=99.9%
     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=0.1%, >=64=0.0%
     issued rwts: total=3896888,0,0,0 short=0,0,0,0 dropped=0,0,0,0
     latency   : target=0, window=0, percentile=100.00%, depth=64

Run status group 0 (all jobs):
   READ: bw=254MiB/s (266MB/s), 254MiB/s-254MiB/s (266MB/s-266MB/s), io=14.9GiB (16.0GB), run=60041-60041msec

Disk stats (read/write):
  nvme1n1: ios=0/0, merge=0/0, ticks=0/0, in_queue=0, util=0.00%
RANDREAD: (g=0): rw=randread, bs=(R) 4096B-4096B, (W) 4096B-4096B, (T) 4096B-4096B, ioengine=libaio, iodepth=64
...
fio-3.27
Starting 48 processes
Jobs: 48 (f=48): [r(48)][100.0%][r=253MiB/s][r=64.9k IOPS][eta 00m:00s]
RANDREAD: (groupid=0, jobs=48): err= 0: pid=7470: Thu Jan 27 18:30:15 2022
  read: IOPS=64.9k, BW=254MiB/s (266MB/s)(14.9GiB/60041msec)
    slat (nsec): min=962, max=47238k, avg=3900.68, stdev=102522.05
    clat (usec): min=211, max=139068, avg=47297.25, stdev=10569.79
     lat (usec): min=1274, max=147957, avg=47301.26, stdev=10569.35
    clat percentiles (msec):
     |  1.00th=[   27],  5.00th=[   30], 10.00th=[   32], 20.00th=[   41],
     | 30.00th=[   44], 40.00th=[   45], 50.00th=[   47], 60.00th=[   48],
     | 70.00th=[   52], 80.00th=[   58], 90.00th=[   62], 95.00th=[   65],
     | 99.00th=[   73], 99.50th=[   77], 99.90th=[   86], 99.95th=[   93],
     | 99.99th=[  106]
   bw (  KiB/s): min=217716, max=298751, per=100.00%, avg=259905.72, stdev=306.13, samples=5664
   iops        : min=54409, max=74668, avg=64959.92, stdev=76.55, samples=5664
  lat (usec)   : 250=0.01%, 500=0.01%, 1000=0.01%
  lat (msec)   : 2=0.01%, 4=0.01%, 10=0.03%, 20=0.30%, 50=66.07%
  lat (msec)   : 100=33.57%, 250=0.02%
  cpu          : usr=0.21%, sys=0.47%, ctx=204669, majf=0, minf=3815
  IO depths    : 1=0.1%, 2=0.1%, 4=0.1%, 8=0.1%, 16=0.1%, 32=0.1%, >=64=99.9%
     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=0.1%, >=64=0.0%
     issued rwts: total=3898180,0,0,0 short=0,0,0,0 dropped=0,0,0,0
     latency   : target=0, window=0, percentile=100.00%, depth=64

Run status group 0 (all jobs):
   READ: bw=254MiB/s (266MB/s), 254MiB/s-254MiB/s (266MB/s-266MB/s), io=14.9GiB (16.0GB), run=60041-60041msec

Disk stats (read/write):
  nvme1n1: ios=0/0, merge=0/0, ticks=0/0, in_queue=0, util=0.00%
RANDREAD: (g=0): rw=randread, bs=(R) 4096B-4096B, (W) 4096B-4096B, (T) 4096B-4096B, ioengine=libaio, iodepth=64
...
fio-3.27
Starting 48 processes
Jobs: 48 (f=48): [r(48)][100.0%][r=252MiB/s][r=64.6k IOPS][eta 00m:00s]
RANDREAD: (groupid=0, jobs=48): err= 0: pid=7520: Thu Jan 27 18:31:16 2022
  read: IOPS=64.9k, BW=254MiB/s (266MB/s)(14.9GiB/60045msec)
    slat (nsec): min=952, max=62060k, avg=5386.66, stdev=203889.44
    clat (usec): min=55, max=152052, avg=47291.79, stdev=10952.81
     lat (usec): min=656, max=172623, avg=47297.29, stdev=10959.29
    clat percentiles (msec):
     |  1.00th=[   27],  5.00th=[   30], 10.00th=[   32], 20.00th=[   41],
     | 30.00th=[   44], 40.00th=[   45], 50.00th=[   47], 60.00th=[   48],
     | 70.00th=[   52], 80.00th=[   58], 90.00th=[   62], 95.00th=[   65],
     | 99.00th=[   74], 99.50th=[   80], 99.90th=[  102], 99.95th=[  110],
     | 99.99th=[  125]
   bw (  KiB/s): min=196644, max=301084, per=100.00%, avg=259941.97, stdev=341.90, samples=5664
   iops        : min=49145, max=75254, avg=64969.79, stdev=85.50, samples=5664
  lat (usec)   : 100=0.01%, 250=0.01%, 500=0.01%, 750=0.01%, 1000=0.01%
  lat (msec)   : 2=0.01%, 4=0.01%, 10=0.06%, 20=0.42%, 50=66.06%
  lat (msec)   : 100=33.34%, 250=0.11%
  cpu          : usr=0.21%, sys=0.47%, ctx=204667, majf=0, minf=3732
  IO depths    : 1=0.1%, 2=0.1%, 4=0.1%, 8=0.1%, 16=0.1%, 32=0.1%, >=64=99.9%
     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=0.1%, >=64=0.0%
     issued rwts: total=3898567,0,0,0 short=0,0,0,0 dropped=0,0,0,0
     latency   : target=0, window=0, percentile=100.00%, depth=64

Run status group 0 (all jobs):
   READ: bw=254MiB/s (266MB/s), 254MiB/s-254MiB/s (266MB/s-266MB/s), io=14.9GiB (16.0GB), run=60045-60045msec

Disk stats (read/write):
  nvme1n1: ios=0/0, merge=0/0, ticks=0/0, in_queue=0, util=0.00%
RANDREAD: (g=0): rw=randread, bs=(R) 4096B-4096B, (W) 4096B-4096B, (T) 4096B-4096B, ioengine=libaio, iodepth=64
...
fio-3.27
Starting 48 processes
Jobs: 48 (f=48): [r(48)][100.0%][r=291MiB/s][r=74.5k IOPS][eta 00m:00s]
RANDREAD: (groupid=0, jobs=48): err= 0: pid=7573: Thu Jan 27 18:32:16 2022
  read: IOPS=69.3k, BW=271MiB/s (284MB/s)(15.9GiB/60037msec)
    slat (nsec): min=962, max=119889k, avg=6570.81, stdev=271570.85
    clat (nsec): min=1784, max=265702k, avg=44292797.24, stdev=11045197.81
     lat (usec): min=937, max=265705, avg=44299.48, stdev=11056.26
    clat percentiles (msec):
     |  1.00th=[   24],  5.00th=[   28], 10.00th=[   30], 20.00th=[   34],
     | 30.00th=[   42], 40.00th=[   43], 50.00th=[   45], 60.00th=[   46],
     | 70.00th=[   48], 80.00th=[   53], 90.00th=[   59], 95.00th=[   63],
     | 99.00th=[   73], 99.50th=[   79], 99.90th=[   99], 99.95th=[  107],
     | 99.99th=[  127]
   bw (  KiB/s): min=196140, max=336434, per=100.00%, avg=277459.75, stdev=548.59, samples=5664
   iops        : min=49018, max=84092, avg=69348.58, stdev=137.14, samples=5664
  lat (usec)   : 2=0.01%, 50=0.01%, 100=0.01%, 250=0.01%, 500=0.01%
  lat (usec)   : 750=0.01%, 1000=0.01%
  lat (msec)   : 2=0.01%, 4=0.01%, 10=0.07%, 20=0.77%, 50=75.42%
  lat (msec)   : 100=23.63%, 250=0.09%, 500=0.01%
  cpu          : usr=0.21%, sys=0.49%, ctx=207302, majf=0, minf=3740
  IO depths    : 1=0.1%, 2=0.1%, 4=0.1%, 8=0.1%, 16=0.1%, 32=0.1%, >=64=99.9%
     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=0.1%, >=64=0.0%
     issued rwts: total=4162006,0,0,0 short=0,0,0,0 dropped=0,0,0,0
     latency   : target=0, window=0, percentile=100.00%, depth=64

Run status group 0 (all jobs):
   READ: bw=271MiB/s (284MB/s), 271MiB/s-271MiB/s (284MB/s-284MB/s), io=15.9GiB (17.0GB), run=60037-60037msec

Disk stats (read/write):
  nvme1n1: ios=0/0, merge=0/0, ticks=0/0, in_queue=0, util=0.00%
RANDREAD: (g=0): rw=randread, bs=(R) 4096B-4096B, (W) 4096B-4096B, (T) 4096B-4096B, ioengine=libaio, iodepth=64
...
fio-3.27
Starting 48 processes
Jobs: 48 (f=48): [r(48)][100.0%][r=255MiB/s][r=65.2k IOPS][eta 00m:00s]
RANDREAD: (groupid=0, jobs=48): err= 0: pid=7627: Thu Jan 27 18:33:16 2022
  read: IOPS=64.7k, BW=253MiB/s (265MB/s)(14.8GiB/60041msec)
    slat (nsec): min=941, max=90920k, avg=7000.17, stdev=307653.58
    clat (usec): min=80, max=231950, avg=47434.66, stdev=11193.75
     lat (usec): min=580, max=231953, avg=47441.78, stdev=11207.19
    clat percentiles (msec):
     |  1.00th=[   26],  5.00th=[   30], 10.00th=[   32], 20.00th=[   41],
     | 30.00th=[   44], 40.00th=[   45], 50.00th=[   47], 60.00th=[   49],
     | 70.00th=[   52], 80.00th=[   58], 90.00th=[   62], 95.00th=[   65],
     | 99.00th=[   77], 99.50th=[   83], 99.90th=[  105], 99.95th=[  113],
     | 99.99th=[  146]
   bw (  KiB/s): min=187097, max=307908, per=100.00%, avg=259134.59, stdev=371.45, samples=5664
   iops        : min=46756, max=76958, avg=64767.39, stdev=92.88, samples=5664
  lat (usec)   : 100=0.01%, 250=0.01%, 500=0.01%, 750=0.01%, 1000=0.01%
  lat (msec)   : 2=0.01%, 4=0.01%, 10=0.07%, 20=0.50%, 50=65.49%
  lat (msec)   : 100=33.78%, 250=0.14%
  cpu          : usr=0.20%, sys=0.47%, ctx=204191, majf=0, minf=3734
  IO depths    : 1=0.1%, 2=0.1%, 4=0.1%, 8=0.1%, 16=0.1%, 32=0.1%, >=64=99.9%
     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=0.1%, >=64=0.0%
     issued rwts: total=3886625,0,0,0 short=0,0,0,0 dropped=0,0,0,0
     latency   : target=0, window=0, percentile=100.00%, depth=64

Run status group 0 (all jobs):
   READ: bw=253MiB/s (265MB/s), 253MiB/s-253MiB/s (265MB/s-265MB/s), io=14.8GiB (15.9GB), run=60041-60041msec

Disk stats (read/write):
  nvme1n1: ios=0/0, merge=0/0, ticks=0/0, in_queue=0, util=0.00%


-- 
2.29.0



^ permalink raw reply	[flat|nested] 5+ messages in thread

* [PATCH V2 1/2] nvmet: use i_size_read() to set size for file-ns
  2022-01-28  8:51 [PATCH V2 0/2] nvmet: add buffered_io support for bdev-ns Chaitanya Kulkarni
@ 2022-01-28  8:51 ` Chaitanya Kulkarni
  2022-01-28  8:51 ` [PATCH V2 2/2] nvmet: allow bdev in buffered_io mode Chaitanya Kulkarni
  1 sibling, 0 replies; 5+ messages in thread
From: Chaitanya Kulkarni @ 2022-01-28  8:51 UTC (permalink / raw)
  To: linux-nvme; +Cc: hch, kbusch, sagi, Chaitanya Kulkarni

From: Chaitanya Kulkarni <kch@nvidia.com>

Instead of calling vfs_getattr() use i_size_read() to read the size of
file so we can read the size of not only file type but also block type
with one call. This is needed to implement buffered_io support for the
NVMeOF block device backend.

We also change return type of function nvmet_file_ns_revalidate() from
int to void, since this function does not return any meaning value.

Signed-off-by: Chaitanya Kulkarni <kch@nvidia.com>
---
 drivers/nvme/target/io-cmd-file.c | 17 ++++-------------
 drivers/nvme/target/nvmet.h       |  2 +-
 2 files changed, 5 insertions(+), 14 deletions(-)

diff --git a/drivers/nvme/target/io-cmd-file.c b/drivers/nvme/target/io-cmd-file.c
index 6be6e59d273b..6485dc8eb974 100644
--- a/drivers/nvme/target/io-cmd-file.c
+++ b/drivers/nvme/target/io-cmd-file.c
@@ -14,16 +14,9 @@
 #define NVMET_MAX_MPOOL_BVEC		16
 #define NVMET_MIN_MPOOL_OBJ		16
 
-int nvmet_file_ns_revalidate(struct nvmet_ns *ns)
+void nvmet_file_ns_revalidate(struct nvmet_ns *ns)
 {
-	struct kstat stat;
-	int ret;
-
-	ret = vfs_getattr(&ns->file->f_path, &stat, STATX_SIZE,
-			  AT_STATX_FORCE_SYNC);
-	if (!ret)
-		ns->size = stat.size;
-	return ret;
+	ns->size = i_size_read(ns->file->f_mapping->host);
 }
 
 void nvmet_file_ns_disable(struct nvmet_ns *ns)
@@ -43,7 +36,7 @@ void nvmet_file_ns_disable(struct nvmet_ns *ns)
 int nvmet_file_ns_enable(struct nvmet_ns *ns)
 {
 	int flags = O_RDWR | O_LARGEFILE;
-	int ret;
+	int ret = 0;
 
 	if (!ns->buffered_io)
 		flags |= O_DIRECT;
@@ -57,9 +50,7 @@ int nvmet_file_ns_enable(struct nvmet_ns *ns)
 		return ret;
 	}
 
-	ret = nvmet_file_ns_revalidate(ns);
-	if (ret)
-		goto err;
+	nvmet_file_ns_revalidate(ns);
 
 	/*
 	 * i_blkbits can be greater than the universally accepted upper bound,
diff --git a/drivers/nvme/target/nvmet.h b/drivers/nvme/target/nvmet.h
index af193423c10b..69637bf8f8e1 100644
--- a/drivers/nvme/target/nvmet.h
+++ b/drivers/nvme/target/nvmet.h
@@ -541,7 +541,7 @@ u16 nvmet_bdev_flush(struct nvmet_req *req);
 u16 nvmet_file_flush(struct nvmet_req *req);
 void nvmet_ns_changed(struct nvmet_subsys *subsys, u32 nsid);
 void nvmet_bdev_ns_revalidate(struct nvmet_ns *ns);
-int nvmet_file_ns_revalidate(struct nvmet_ns *ns);
+void nvmet_file_ns_revalidate(struct nvmet_ns *ns);
 void nvmet_ns_revalidate(struct nvmet_ns *ns);
 u16 blk_to_nvme_status(struct nvmet_req *req, blk_status_t blk_sts);
 
-- 
2.29.0



^ permalink raw reply related	[flat|nested] 5+ messages in thread

* [PATCH V2 2/2] nvmet: allow bdev in buffered_io mode
  2022-01-28  8:51 [PATCH V2 0/2] nvmet: add buffered_io support for bdev-ns Chaitanya Kulkarni
  2022-01-28  8:51 ` [PATCH V2 1/2] nvmet: use i_size_read() to set size for file-ns Chaitanya Kulkarni
@ 2022-01-28  8:51 ` Chaitanya Kulkarni
  2022-02-01  8:05   ` Christoph Hellwig
  1 sibling, 1 reply; 5+ messages in thread
From: Chaitanya Kulkarni @ 2022-01-28  8:51 UTC (permalink / raw)
  To: linux-nvme; +Cc: hch, kbusch, sagi, Chaitanya Kulkarni

From: Chaitanya Kulkarni <kch@nvidia.com>

Allow block device to be configured in the buffered I/O mode by using
the file backend. In this way now we can use cache for the block
device namespace which shows significant performance improvement.

We update the block device ns enable function and return early when
buffered_io flag is set.

Signed-off-by: Chaitanya Kulkarni <kch@nvidia.com>
---
 drivers/nvme/target/io-cmd-bdev.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/nvme/target/io-cmd-bdev.c b/drivers/nvme/target/io-cmd-bdev.c
index 70ca9dfc1771..7f6dee625f7b 100644
--- a/drivers/nvme/target/io-cmd-bdev.c
+++ b/drivers/nvme/target/io-cmd-bdev.c
@@ -76,6 +76,9 @@ int nvmet_bdev_ns_enable(struct nvmet_ns *ns)
 {
 	int ret;
 
+	if (ns->buffered_io)
+		return -ENOTBLK;
+
 	ns->bdev = blkdev_get_by_path(ns->device_path,
 			FMODE_READ | FMODE_WRITE, NULL);
 	if (IS_ERR(ns->bdev)) {
-- 
2.29.0



^ permalink raw reply related	[flat|nested] 5+ messages in thread

* Re: [PATCH V2 2/2] nvmet: allow bdev in buffered_io mode
  2022-01-28  8:51 ` [PATCH V2 2/2] nvmet: allow bdev in buffered_io mode Chaitanya Kulkarni
@ 2022-02-01  8:05   ` Christoph Hellwig
  2022-02-02  6:49     ` Chaitanya Kulkarni
  0 siblings, 1 reply; 5+ messages in thread
From: Christoph Hellwig @ 2022-02-01  8:05 UTC (permalink / raw)
  To: Chaitanya Kulkarni; +Cc: linux-nvme, hch, kbusch, sagi, Chaitanya Kulkarni

On Fri, Jan 28, 2022 at 12:51:48AM -0800, Chaitanya Kulkarni wrote:
> +	if (ns->buffered_io)
> +		return -ENOTBLK;

Maybe add a comment here that we want to force a fallback to the file
backend for buffered I/O here as this check on it's own isn't totally
obvious.

Otherwise the series looks good to me.


^ permalink raw reply	[flat|nested] 5+ messages in thread

* Re: [PATCH V2 2/2] nvmet: allow bdev in buffered_io mode
  2022-02-01  8:05   ` Christoph Hellwig
@ 2022-02-02  6:49     ` Chaitanya Kulkarni
  0 siblings, 0 replies; 5+ messages in thread
From: Chaitanya Kulkarni @ 2022-02-02  6:49 UTC (permalink / raw)
  To: Christoph Hellwig; +Cc: linux-nvme, kbusch, sagi, Chaitanya Kulkarni

On 2/1/22 12:05 AM, Christoph Hellwig wrote:
> External email: Use caution opening links or attachments
> 
> 
> On Fri, Jan 28, 2022 at 12:51:48AM -0800, Chaitanya Kulkarni wrote:
>> +     if (ns->buffered_io)
>> +             return -ENOTBLK;
> 
> Maybe add a comment here that we want to force a fallback to the file
> backend for buffered I/O here as this check on it's own isn't totally
> obvious.
> 
> Otherwise the series looks good to me.
> 

Okay will sendout a v3 with added comment, I guess had it in V1
forgot in V2.


^ permalink raw reply	[flat|nested] 5+ messages in thread

end of thread, other threads:[~2022-02-02  6:49 UTC | newest]

Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2022-01-28  8:51 [PATCH V2 0/2] nvmet: add buffered_io support for bdev-ns Chaitanya Kulkarni
2022-01-28  8:51 ` [PATCH V2 1/2] nvmet: use i_size_read() to set size for file-ns Chaitanya Kulkarni
2022-01-28  8:51 ` [PATCH V2 2/2] nvmet: allow bdev in buffered_io mode Chaitanya Kulkarni
2022-02-01  8:05   ` Christoph Hellwig
2022-02-02  6:49     ` Chaitanya Kulkarni

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