## 簡介

 

Blobstore是構建在spdk bdev層的一個邏輯對象管理層，每個blob對應一個對象，一個blob被邏輯上拆分成很多不連續的cluster，每個cluster又分為page。blobstore將blob元數據記錄在磁盤頭相關的page頁，整個IO流都在用戶態，具有非常好的讀寫性能，并具備掉電恢復等故障處理能力。

 

 

## 實踐

*** 格式化一個NVMe設備為blobstore引擎 ***

```shell

[root@test examples]# cat blobcli.json

{

"subsystems": [

{

"subsystem":"bdev",

"config": [

{

"method":"bdev_nvme_attach_controller",

"params":{

"trtype":"PCIe",

"name":"Nvme1",

"traddr":"0000:68:00.0"

}

}

]

}

]

}

# -b 一定是 name+n1 這樣子格式

[root@test examples]# ./blobcli -b Nvme1n1 -i blobcli.json

Your entire blobstore will be destroyed. Are you sure? (y/n) y

[2024-04-10 17:04:12.916671] Starting SPDK v23.01.1 git sha1 186986c / DPDK 22.11.1 initialization...

[2024-04-10 17:04:12.918661] [ DPDK EAL parameters: blobcli --no-shconf -c 0x1 --huge-unlink --log-level=lib.eal:6 --log-level=lib.cryptodev:5 --log-level=user1:6 --iova-mode=pa --base-virtaddr=0x200000000000 --match-allocations --file-prefix=spdk_pid3670165 ]

TELEMETRY: No legacy callbacks, legacy socket not created

[2024-04-10 17:04:13.073398] app.c: 712:spdk_app_start: *NOTICE*: Total cores available: 1

[2024-04-10 17:04:13.120114] reactor.c: 926:reactor_run: *NOTICE*: Reactor started on core 0

[2024-04-10 17:04:13.141979] accel_sw.c: 681:sw_accel_module_init: *NOTICE*: Accel framework software module initialized.

Init blobstore using bdev Name: Nvme1n1

blobstore init'd: (0x175f130)

```

*** 創建一個blob ***

```shell

# blobstore還是構建在bdev層之上的

[root@test examples]# ./blobcli -b Nvme1n1 -l bdevs

List bdevs:

bdevName:Nvme1n1

bdevProductName:NVMedisk

[root@test examples]# ./blobcli -b Nvme1n1 -n 1

New blob id 0x100000000

blob now has USED clusters of 1

[root@slg-poc-x86-ceph-1 examples]# ./blobcli -b Nvme1n1 -l blobs

List BLOBS:

Found blob with ID# 0x100000000

[root@test examples]# ./blobcli -b Nvme1n1 -s 0x100000000

Blob Public Info:

blob ID: 0x100000000

# of clusters: 1

# of bytes: 1048576

# of pages: 256

# of xattrs: 0

xattrs:

Blob Private Info:

state: CLEAN

open ref count: 1

[root@test examples]# ./blobcli -b Nvme1n1 -s bs

Blobstore Public Info:

UsingbdevProductName:NVMedisk

APIVersion:3

superblobID:noneassigned

pagesize:4096

iounitsize:512

clustersize:1048576

# free clusters: 7297030

blobstoretype:

00000000 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................

Blobstore Private Info:

Metadatastart (pages): 673

Metadatalength (pages): 7325650

```

*** 讀寫一個blob ***

```shell

[root@test examples]# ./blobcli -b Nvme1n1 -m 0x100000000 test

[root@test examples]# ./blobcli -b Nvme1n1 -d 0x100000000 test1

```