我想我对当前的服务器设置有点迷失了。它是 HP Proliant dl160 gen 6，我放置了 4 个旋转磁盘，其设置具有 mdmadm + luks + lvm 和 btrfs（也许我走得太远了？），它读取的 IO 速度确实受到了影响50MB/s 和 2MB/s 左右的写入速度，我感觉我搞砸了。
我注意到的一件事是我在块设备（sbd）上而不是在分区（sdb1）上设置了 mdadm，这会影响什么吗？
在这里可以看到fio --name=randwrite --rw=randwrite --direct=1 --bs=16k --numjobs=128 --size=200M --runtime=60 --group_reporting机器上几乎没有用的时候fio的输出。
randwrite: (groupid=0, jobs=128): err= 0: pid=54290: Tue Oct 26 16:21:50 2021
write: IOPS=137, BW=2193KiB/s (2246kB/s)(131MiB/61080msec); 0 zone resets
clat (msec): min=180, max=2784, avg=924.48, stdev=318.02
lat (msec): min=180, max=2784, avg=924.48, stdev=318.02
clat percentiles (msec):
| 1.00th=[ 405], 5.00th=[ 542], 10.00th=[ 600], 20.00th=[ 693],
| 30.00th=[ 760], 40.00th=[ 818], 50.00th=[ 860], 60.00th=[ 927],
| 70.00th=[ 1011], 80.00th=[ 1133], 90.00th=[ 1267], 95.00th=[ 1452],
| 99.00th=[ 2165], 99.50th=[ 2232], 99.90th=[ 2635], 99.95th=[ 2769],
| 99.99th=[ 2769]
bw ( KiB/s): min= 3972, max= 4735, per=100.00%, avg=4097.79, stdev= 1.58, samples=8224
iops : min= 132, max= 295, avg=248.40, stdev= 0.26, samples=8224
lat (msec) : 250=0.04%, 500=2.82%, 750=25.96%, 1000=40.58%, 2000=28.67%
lat (msec) : >=2000=1.95%
cpu : usr=0.00%, sys=0.01%, ctx=18166, majf=0, minf=1412
IO depths : 1=100.0%, 2=0.0%, 4=0.0%, 8=0.0%, 16=0.0%, 32=0.0%, >=64=0.0%
submit : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, 32=0.0%, 64=0.0%, >=64=0.0%
complete : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, 32=0.0%, 64=0.0%, >=64=0.0%
issued rwts: total=0,8372,0,0 short=0,0,0,0 dropped=0,0,0,0
latency : target=0, window=0, percentile=100.00%, depth=1
Run status group 0 (all jobs):
WRITE: bw=2193KiB/s (2246kB/s), 2193KiB/s-2193KiB/s (2246kB/s-2246kB/s), io=131MiB (137MB), run=61080-61080msec
使用 dd 更新 1 次顺序写入
root@hp-proliant-dl160-g6-1:~# dd if=/dev/zero of=disk-test oflag=direct bs=512k count=100
100+0 records in 100+0 records out 52428800 bytes (52 MB, 50 MiB) copied, 5.81511 s, 9.0 MB/s
内核：5.4.0-89-generic
操作系统：Ubuntu 20.04.3
mdadm：4.1-5ubuntu1.2
lvm2：2.03.07-1ubuntu1
blkid 输出
/dev/mapper/dm_crypt-0: UUID="r7TBdk-1GZ4-zbUh-007u-BfuP-dtis-bTllYi" TYPE="LVM2_member"
/dev/sda2: UUID="64528d97-f05c-4f34-a238-f7b844b3bb58" UUID_SUB="263ae70e-d2b8-4dfe-bc6b-bbc2251a9f32" TYPE="btrfs" PARTUUID="494be592-3dad-4600-b954-e2912e410b8b"
/dev/sdb: UUID="478e8132-7783-1fb1-936a-358d06dbd871" UUID_SUB="4aeb4804-6380-5421-6aea-d090e6aea8a0" LABEL="ubuntu-server:0" TYPE="linux_raid_member"
/dev/sdc: UUID="478e8132-7783-1fb1-936a-358d06dbd871" UUID_SUB="9d5a4ddd-bb9e-bb40-9b21-90f4151a5875" LABEL="ubuntu-server:0" TYPE="linux_raid_member"
/dev/sdd: UUID="478e8132-7783-1fb1-936a-358d06dbd871" UUID_SUB="f08b5e6d-f971-c622-cd37-50af8ff4b308" LABEL="ubuntu-server:0" TYPE="linux_raid_member"
/dev/sde: UUID="478e8132-7783-1fb1-936a-358d06dbd871" UUID_SUB="362025d4-a4d2-8727-6853-e503c540c4f7" LABEL="ubuntu-server:0" TYPE="linux_raid_member"
/dev/md0: UUID="a5b5bf95-1ff1-47f9-b3f6-059356e3af41" TYPE="crypto_LUKS"
/dev/mapper/vg0-lv--0: UUID="6db4e233-5d97-46d2-ac11-1ce6c72f5352" TYPE="swap"
/dev/mapper/vg0-lv--1: UUID="4e1a5131-cb91-48c4-8266-5b165d9f5071" UUID_SUB="e5fc407e-57c2-43eb-9b66-b00207ea6d91" TYPE="btrfs"
/dev/loop0: TYPE="squashfs"
/dev/loop1: TYPE="squashfs"
/dev/loop2: TYPE="squashfs"
/dev/loop3: TYPE="squashfs"
/dev/loop4: TYPE="squashfs"
/dev/loop5: TYPE="squashfs"
/dev/loop6: TYPE="squashfs"
/dev/loop7: TYPE="squashfs"
/dev/loop8: TYPE="squashfs"
/dev/loop9: TYPE="squashfs"
/dev/loop10: TYPE="squashfs"
/dev/sda1: PARTUUID="fa30c3f5-6952-45f0-b844-9bfb46fa0224"
猫 /proc/mdstat
Personalities : [raid6] [raid5] [raid4] [linear] [multipath] [raid0] [raid1] [raid10]
md0 : active raid5 sdb[0] sdc[1] sdd[2] sde[4]
5860147200 blocks super 1.2 level 5, 512k chunk, algorithm 2 [4/4] [UUUU]
bitmap: 2/15 pages [8KB], 65536KB chunk
unused devices: <none>
lshw -c 磁盘
*-disk
description: SCSI Disk
product: DT 101 G2
vendor: Kingston
physical id: 0.0.0
bus info: scsi@0:0.0.0
logical name: /dev/sda
version: 1.00
serial: xxxxxxxxxxxxxxxxxxxx
size: 7643MiB (8015MB)
capabilities: removable
configuration: ansiversion=4 logicalsectorsize=512 sectorsize=512
*-medium
physical id: 0
logical name: /dev/sda
size: 7643MiB (8015MB)
capabilities: gpt-1.00 partitioned partitioned:gpt
configuration: guid=6c166e3e-27c9-4edf-9b0d-e21892cbce41
*-disk
description: ATA Disk
product: ST2000DM008-2FR1
physical id: 0.0.0
bus info: scsi@1:0.0.0
logical name: /dev/sdb
version: 0001
serial: xxxxxxxxxxxxxxxxxxxx
size: 1863GiB (2TB)
capabilities: removable
configuration: ansiversion=5 logicalsectorsize=512 sectorsize=4096
*-medium
physical id: 0
logical name: /dev/sdb
size: 1863GiB (2TB)
*-disk
description: ATA Disk
product: ST2000DM008-2FR1
physical id: 0.0.0
bus info: scsi@2:0.0.0
logical name: /dev/sdc
version: 0001
serial: xxxxxxxxxxxxxxxxxxxx
size: 1863GiB (2TB)
capabilities: removable
configuration: ansiversion=5 logicalsectorsize=512 sectorsize=4096
*-medium
physical id: 0
logical name: /dev/sdc
size: 1863GiB (2TB)
*-disk
description: ATA Disk
product: WDC WD20EZBX-00A
vendor: Western Digital
physical id: 0.0.0
bus info: scsi@3:0.0.0
logical name: /dev/sdd
version: 1A01
serial: xxxxxxxxxxxxxxxxxxxx
size: 1863GiB (2TB)
capabilities: removable
configuration: ansiversion=5 logicalsectorsize=512 sectorsize=4096
*-medium
physical id: 0
logical name: /dev/sdd
size: 1863GiB (2TB)
*-disk
description: ATA Disk
product: WDC WD20EZBX-00A
vendor: Western Digital
physical id: 0.0.0
bus info: scsi@4:0.0.0
logical name: /dev/sde
version: 1A01
serial: xxxxxxxxxxxxxxxxxxxx
size: 1863GiB (2TB)
capabilities: removable
configuration: ansiversion=5 logicalsectorsize=512 sectorsize=4096
*-medium
physical id: 0
logical name: /dev/sde
size: 1863GiB (2TB)
您在设置中看到任何可能有问题的地方吗？您认为添加带有 PCI 卡的 nvme 并将其用于缓存会有所帮助吗？