搭建实验环境

brew install lima

# 创建 4 块 20 GB 的空白数据盘
for i in 1 2 3 4; do limactl disk create sj-d$i --size 20G; done

# 创建并启动虚拟机：4 核 / 8 GB / 40 GB 系统盘，挂上 4 块数据盘且不自动格式化
limactl start --name=sj --cpus=4 --memory=8 --disk=40 --tty=false \
  --set '.additionalDisks = [
    {"name":"sj-d1","format":false},
    {"name":"sj-d2","format":false},
    {"name":"sj-d3","format":false},
    {"name":"sj-d4","format":false}]' \
  template://ubuntu-24.04

# 进入虚拟机
limactl shell sj

New-Item -ItemType Directory -Path C:\VMs\sj
New-VM -Name sj -Generation 2 -MemoryStartupBytes 8GB `
  -NewVHDPath C:\VMs\sj\os.vhdx -NewVHDSizeBytes 40GB -SwitchName "Default Switch"
Set-VMProcessor -VMName sj -Count 4
Set-VMFirmware -VMName sj -SecureBootTemplate MicrosoftUEFICertificateAuthority
Add-VMDvdDrive -VMName sj -Path C:\ISO\ubuntu-24.04-live-server-amd64.iso
Set-VMFirmware -VMName sj -FirstBootDevice (Get-VMDvdDrive -VMName sj)

# 4 块动态扩展的数据盘
1..4 | ForEach-Object {
  New-VHD -Path "C:\VMs\sj\d$_.vhdx" -SizeBytes 20GB -Dynamic
  Add-VMHardDiskDrive -VMName sj -Path "C:\VMs\sj\d$_.vhdx"
}
Start-VM -Name sj

sudo qemu-img create -f qcow2 /var/lib/libvirt/images/sj-d1.qcow2 20G
sudo virsh attach-disk sj /var/lib/libvirt/images/sj-d1.qcow2 vdb \
  --driver qemu --subdriver qcow2 --targetbus virtio --persistent

$ sudo apt update && sudo apt -y full-upgrade
$ uname -r
6.8.0-79-generic
$ grep VERSION= /etc/os-release
VERSION="24.04.3 LTS (Noble Numbat)"
$ lsblk
NAME    MAJ:MIN RM  SIZE RO TYPE MOUNTPOINTS
vda     253:0    0   40G  0 disk
├─vda1  253:1    0 39.9G  0 part /
├─vda15 253:15   0   99M  0 part /boot/efi
└─vda16 259:0    0  923M  0 part /boot
vdb     253:16   0  366M  1 disk
vdc     253:32   0   20G  0 disk
vdd     253:48   0   20G  0 disk
vde     253:64   0   20G  0 disk
vdf     253:80   0   20G  0 disk

sudo apt update
sudo apt install -y \
  fio sysstat iotop-c blktrace ioping strace \
  bpfcc-tools bpftrace linux-headers-$(uname -r) \
  nvme-cli smartmontools hdparm sg3-utils \
  lvm2 xfsprogs e2fsprogs btrfs-progs gdisk parted jq
# mdadm 默认会推荐安装邮件服务（用于告警邮件），实验机不需要
sudo apt install -y --no-install-recommends mdadm

sudo sed -i 's/^ENABLED="false"/ENABLED="true"/' /etc/default/sysstat
sudo systemctl enable --now sysstat

$ sudo bpftrace -e 'kprobe:vfs_read { @[comm] = count(); } interval:s:3 { exit(); }'
Attaching 2 probes...

@[systemd-journal]: 12
@[bash]: 21
@[sshd]: 38
$ sudo biolatency-bpfcc 3 1
Tracing block device I/O... Hit Ctrl-C to end.

     usecs               : count     distribution
        64 -> 127        : 3        |*************                           |
       128 -> 255        : 9        |****************************************|
       256 -> 511        : 2        |********                                |

$ sudo mkdir -p /var/lib/sj-disks && sudo truncate -s 10G /var/lib/sj-disks/disk1.img
$ du -h --apparent-size /var/lib/sj-disks/disk1.img; du -h /var/lib/sj-disks/disk1.img
10G     /var/lib/sj-disks/disk1.img
0       /var/lib/sj-disks/disk1.img
$ sudo losetup -f -P --show --direct-io=on /var/lib/sj-disks/disk1.img
/dev/loop8
$ losetup -l /dev/loop8
NAME       SIZELIMIT OFFSET AUTOCLEAR RO BACK-FILE                    DIO LOG-SEC
/dev/loop8         0      0         0  0 /var/lib/sj-disks/disk1.img   1     512

#!/usr/bin/env bash
# 创建并挂接 storage-journey 实验用的 loop 盘：sj-loop.sh [数量] [大小]
set -euo pipefail
DIR=/var/lib/sj-disks
N=${1:-4}
SIZE=${2:-10G}
mkdir -p "$DIR"
for i in $(seq 1 "$N"); do
  img="$DIR/disk$i.img"
  [ -f "$img" ] || truncate -s "$SIZE" "$img"
  # 已经挂接过就跳过
  if [ -z "$(losetup -j "$img")" ]; then
    losetup -f -P --direct-io=on "$img"
  fi
done
losetup -l | awk 'NR==1 || /sj-disks/'

[Unit]
Description=Attach storage-journey loop disks
After=local-fs.target

[Service]
Type=oneshot
ExecStart=/usr/local/sbin/sj-loop.sh 4 10G
RemainAfterExit=yes

[Install]
WantedBy=multi-user.target

sudo chmod +x /usr/local/sbin/sj-loop.sh
sudo systemctl daemon-reload
sudo systemctl enable --now sj-loop.service
# 不用了就拆掉：sudo losetup -d /dev/loop8，再删除镜像文件

$ sudo modprobe null_blk nr_devices=1 gb=4 bs=4096 queue_mode=2 irqmode=2 completion_nsec=100000
$ lsblk -dno NAME,SIZE /dev/nullb0
nullb0   4G
$ cat /sys/block/nullb0/queue/scheduler
none [mq-deadline]

$ sudo modprobe brd rd_nr=2 rd_size=2097152     # 2 块，每块 2 GiB（单位 KiB）
$ lsblk /dev/ram0 /dev/ram1
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINTS
ram0   1:0    0   2G  0 disk
ram1   1:1    0   2G  0 disk

#!/usr/bin/env bash
# storage-journey 实验环境自检
pass=0; fail=0
check() {
  if eval "$2" >/dev/null 2>&1; then printf '  [OK]   %s\n' "$1"; pass=$((pass+1))
  else printf '  [FAIL] %s\n' "$1"; fail=$((fail+1)); fi
}

echo "== 系统 =="
check "Ubuntu 24.04"      'grep -q "VERSION_ID=\"24.04\"" /etc/os-release'
check "内核 >= 6.8"        'dpkg --compare-versions "$(uname -r | cut -d- -f1)" ge 6.8'
check "内核 BTF 可用"      'test -e /sys/kernel/btf/vmlinux'
check "内存 >= 4 GiB"      '[ "$(awk "/MemTotal/{print \$2}" /proc/meminfo)" -ge 3800000 ]'

echo "== 工具 =="
for c in fio iostat pidstat sar blktrace ioping strace bpftrace biolatency-bpfcc \
         nvme smartctl pvcreate mdadm mkfs.xfs mkfs.ext4 sgdisk; do
  check "$c" "command -v $c"
done
check "bpftrace 能挂内核探针" 'sudo timeout 10 bpftrace -e "kprobe:vfs_read { exit(); }"'

echo "== 数据盘 =="
blank=0
for d in $(lsblk -dnpo NAME,TYPE,RO | awk '($2=="disk" || $2=="loop") && $3=="0" {print $1}'); do
  [ -n "$(lsblk -no FSTYPE,MOUNTPOINTS "$d" | tr -d '[:space:]')" ] && continue
  [ "$(lsblk -dnbo SIZE "$d")" -ge $((5*1024*1024*1024)) ] || continue
  echo "  空白盘: $d $(lsblk -dno SIZE "$d")"; blank=$((blank+1))
done
check "至少 4 块 >= 5 GiB 的空白盘（当前 $blank 块）" "[ $blank -ge 4 ]"

echo "== 结果: $pass 通过, $fail 失败 =="

$ bash sj-check.sh
== 系统 ==
  [OK]   Ubuntu 24.04
  [OK]   内核 >= 6.8
  [OK]   内核 BTF 可用
  [OK]   内存 >= 4 GiB
== 工具 ==
  [OK]   fio
  [OK]   iostat
  ...
  [OK]   bpftrace 能挂内核探针
== 数据盘 ==
  空白盘: /dev/vdc 20G
  空白盘: /dev/vdd 20G
  空白盘: /dev/vde 20G
  空白盘: /dev/vdf 20G
  [OK]   至少 4 块 >= 5 GiB 的空白盘（当前 4 块）
== 结果: 22 通过, 0 失败 ==