我正在运行 Nas4Free 10.2.0.2 - Prester（修订版 1814），它基于 FreeBSD 10.2-RELEASE-p2 #0 r287260M：2015 年 8 月 28 日星期五 18:38:18 CEST。系统有 24 GB 内存。我尝试过ashift=912 和 13，没有区别。
我只有 14.7T 的可用空间。这是为什么？
编辑：我现在已经尝试在同一台机器上使用 OpenIndiana 的 ZFS 实现，它提供了 28.5T 的可用空间，并将驱动器列为 8001.49GB。所以这可能是 FreeBSD 的 ZFS 实现中的错误或 FreeBSD HDD 驱动程序错误？
编辑：我现在已经尝试使用 FreeBSD-10.2-STABLE-amd64-20150917-r287929-memstick.img，它提供了 28.1T 的可用空间，所以这是一个错误。
磁盘：
ada0 at ata2 bus 0 scbus2 target 0 lun 0
ada0: <ST8000AS0002-1NA17Z AR13> ACS-2 ATA SATA 3.x device
ada0: 300.000MB/s transfers (SATA 2.x, UDMA5, PIO 8192bytes)
ada0: 7630885MB (15628053168 512 byte sectors: 16H 63S/T 16383C)
ada1 at ata2 bus 0 scbus2 target 1 lun 0
ada1: <ST8000AS0002-1NA17Z AR13> ACS-2 ATA SATA 3.x device
ada1: 300.000MB/s transfers (SATA 2.x, UDMA5, PIO 8192bytes)
ada1: 7630885MB (15628053168 512 byte sectors: 16H 63S/T 16383C)
ada2 at ata3 bus 0 scbus3 target 0 lun 0
ada2: <ST8000AS0002-1NA17Z AR13> ACS-2 ATA SATA 3.x device
ada2: 300.000MB/s transfers (SATA 2.x, UDMA5, PIO 8192bytes)
ada2: 7630885MB (15628053168 512 byte sectors: 16H 63S/T 16383C)
ada3 at ata3 bus 0 scbus3 target 1 lun 0
ada3: <ST8000AS0002-1NA17Z AR13> ACS-2 ATA SATA 3.x device
ada3: 300.000MB/s transfers (SATA 2.x, UDMA5, PIO 8192bytes)
ada3: 7630885MB (15628053168 512 byte sectors: 16H 63S/T 16383C)
ada4 at ata4 bus 0 scbus4 target 0 lun 0
ada4: <ST8000AS0002-1NA17Z AR13> ACS-2 ATA SATA 3.x device
ada4: 300.000MB/s transfers (SATA 2.x, UDMA5, PIO 8192bytes)
ada4: 7630885MB (15628053168 512 byte sectors: 16H 63S/T 16383C)
ada5 at ata5 bus 0 scbus5 target 0 lun 0
ada5: <ST8000AS0002-1NA17Z AR13> ACS-2 ATA SATA 3.x device
ada5: 300.000MB/s transfers (SATA 2.x, UDMA5, PIO 8192bytes)
ada5: 7630885MB (15628053168 512 byte sectors: 16H 63S/T 16383C)
删除旧尝试和 ZFS 元数据：
storage: /# zpool destroy storage2
storage: /# dd if=/dev/zero of=/dev/ada0 bs=1m count=128
storage: /# dd if=/dev/zero of=/dev/ada1 bs=1m count=128
storage: /# dd if=/dev/zero of=/dev/ada2 bs=1m count=128
storage: /# dd if=/dev/zero of=/dev/ada3 bs=1m count=128
storage: /# dd if=/dev/zero of=/dev/ada4 bs=1m count=128
storage: /# dd if=/dev/zero of=/dev/ada5 bs=1m count=128
storage: /# dd if=/dev/zero of=/dev/ada0 oseek=15628000000
storage: /# dd if=/dev/zero of=/dev/ada1 oseek=15628000000
storage: /# dd if=/dev/zero of=/dev/ada2 oseek=15628000000
storage: /# dd if=/dev/zero of=/dev/ada3 oseek=15628000000
storage: /# dd if=/dev/zero of=/dev/ada4 oseek=15628000000
storage: /# dd if=/dev/zero of=/dev/ada5 oseek=15628000000
创建新池：
storage: /# zpool create storage2 raidz2 ada0 ada1 ada2 ada3 ada4 ada5
zfs 列表：
storage: /# zfs list
NAME USED AVAIL REFER MOUNTPOINT
storage2 432K 14.5T 192K /storage2
iostat：
storage: /# zpool iostat storage2
capacity operations bandwidth
pool alloc free read write read write
---------- ----- ----- ----- ----- ----- -----
storage2 900K 43.5T 0 1 0 7.84K
zpool 列表：
storage: /# zpool list
NAME SIZE ALLOC FREE EXPANDSZ FRAG CAP DEDUP HEALTH ALTROOT
storage2 43.5T 900K 43.5T - 0% 0% 1.00x ONLINE -
zpool状态：
storage: /# zpool status
pool: storage2
state: ONLINE
scan: none requested
config:
NAME STATE READ WRITE CKSUM
storage2 ONLINE 0 0 0
raidz2-0 ONLINE 0 0 0
ada0 ONLINE 0 0 0
ada1 ONLINE 0 0 0
ada2 ONLINE 0 0 0
ada3 ONLINE 0 0 0
ada4 ONLINE 0 0 0
ada5 ONLINE 0 0 0
errors: No known data errors
zfs 列表：
storage: /# zfs list -t all
NAME USED AVAIL REFER MOUNTPOINT
storage2 480K 14.5T 192K /storage2
特性：
# zfs get all storage2
NAME PROPERTY VALUE SOURCE
storage2 type filesystem -
storage2 creation Thu Sep 24 18:48 2015 -
storage2 used 623K -
storage2 available 14.5T -
storage2 referenced 192K -
storage2 compressratio 1.00x -
storage2 mounted yes -
storage2 quota none default
storage2 reservation none default
storage2 recordsize 128K default
storage2 mountpoint /storage2 default
storage2 sharenfs off default
storage2 checksum on default
storage2 compression off default
storage2 atime on default
storage2 devices on default
storage2 exec on default
storage2 setuid on default
storage2 readonly off default
storage2 jailed off default
storage2 snapdir hidden default
storage2 aclmode discard default
storage2 aclinherit restricted default
storage2 canmount on default
storage2 xattr off temporary
storage2 copies 1 default
storage2 version 5 -
storage2 utf8only off -
storage2 normalization none -
storage2 casesensitivity sensitive -
storage2 vscan off default
storage2 nbmand off default
storage2 sharesmb off default
storage2 refquota none default
storage2 refreservation none default
storage2 primarycache all default
storage2 secondarycache all default
storage2 usedbysnapshots 0 -
storage2 usedbydataset 192K -
storage2 usedbychildren 432K -
storage2 usedbyrefreservation 0 -
storage2 logbias latency default
storage2 dedup off default
storage2 mlslabel -
storage2 sync standard default
storage2 refcompressratio 1.00x -
storage2 written 192K -
storage2 logicalused 80K -
storage2 logicalreferenced 9.50K -
storage2 volmode default default
storage2 filesystem_limit none default
storage2 snapshot_limit none default
storage2 filesystem_count none default
storage2 snapshot_count none default
storage2 redundant_metadata all default
豬類
# zdb -C storage2
MOS Configuration:
version: 5000
name: 'storage2'
state: 0
txg: 4
pool_guid: 9410028398282520009
hostid: 1452759488
hostname: 'storage.home'
vdev_children: 1
vdev_tree:
type: 'root'
id: 0
guid: 9410028398282520009
create_txg: 4
children[0]:
type: 'raidz'
id: 0
guid: 16070893740466238556
nparity: 2
metaslab_array: 34
metaslab_shift: 38
ashift: 12
asize: 48009350479872
is_log: 0
create_txg: 4
children[0]:
type: 'disk'
id: 0
guid: 17748612860167792044
path: '/dev/ada0'
phys_path: '/dev/ada0'
whole_disk: 1
create_txg: 4
children[1]:
type: 'disk'
id: 1
guid: 13659584123500602452
path: '/dev/ada1'
phys_path: '/dev/ada1'
whole_disk: 1
create_txg: 4
children[2]:
type: 'disk'
id: 2
guid: 16565608857540887077
path: '/dev/ada2'
phys_path: '/dev/ada2'
whole_disk: 1
create_txg: 4
children[3]:
type: 'disk'
id: 3
guid: 400417648284480610
path: '/dev/ada3'
phys_path: '/dev/ada3'
whole_disk: 1
create_txg: 4
children[4]:
type: 'disk'
id: 4
guid: 15293896650775132923
path: '/dev/ada4'
phys_path: '/dev/ada4'
whole_disk: 1
create_txg: 4
children[5]:
type: 'disk'
id: 5
guid: 14105808749251955600
path: '/dev/ada5'
phys_path: '/dev/ada5'
whole_disk: 1
create_txg: 4
features_for_read:
com.delphix:hole_birth
com.delphix:embedded_data