最後更新: 2024-10-21

目錄

• Compression in ZFS
• ZFS Pool Features

Compression in ZFS

compression is enabled on a dataset (show on `zfs list`)

ZFS tries to compress all new blocks before writing them and decompresses them on reading

Enable Compression

# recommend: lz4 (focused on compression and decompression speed)

zfs set compression=<algorithm> <dataset>

# off

zfs set compression=off <dataset>

ie.

zfs create MyPool/data

zfs set compression=lz4 MyPool/data

Compression Info.

zfs get compression MyPool/data

NAME         PROPERTY     VALUE           SOURCE
MyPool/data  compression  lz4             local

zfs get compressratio MyPool/data compressratio

NAME         PROPERTY       VALUE  SOURCE
MyPool/data  compressratio  1.28x  -

ZFS Pool Features (ZFS pool on-disk format Versions)

 * enabling new features can render a pool not importable by an older version of ZFS

ZFS pool on-disk format versions are specified via "features" which replace the old on-disk format numbers

– allow a uniquely named pool property for each change to the on-disk format.

Feature states:

• active,
• enabled,
• disabled (Features cannot be disabled once they have been enabled.)

Enable a feature

zpool upgrade                                              # All feature

zpool set feature@feature-name=enabled

# Displays a list of file systems that are not the most recent version.

zpool upgrade

# To see what new features the upgrade provides

zpool upgrade -v

VER  DESCRIPTION
---  --------------------------------------------------------
 1   Initial ZFS filesystem version
 2   Enhanced directory entries
 3   Case insensitive and filesystem user identifier (FUID)
 4   userquota, groupquota properties
 5   System attributes

# Upgrades file systems to a new on-disk version

zfs upgrade PoolName