Provided by: zfsutils-linux_2.1.5-1ubuntu6~22.04.4_amd64 bug

NAME

     zpool-features — description of ZFS pool features

DESCRIPTION

     ZFS pool on-disk format versions are specified via "features" which replace the old on-disk
     format numbers (the last supported on-disk format number is 28).  To enable a feature on a
     pool use the zpool upgrade, or set the feature@feature-name property to enabled.  Please
     also see the Compatibility feature sets section for information on how sets of features may
     be enabled together.

     The pool format does not affect file system version compatibility or the ability to send
     file systems between pools.

     Since most features can be enabled independently of each other, the on-disk format of the
     pool is specified by the set of all features marked as active on the pool.  If the pool was
     created by another software version this set may include unsupported features.

   Identifying features
     Every feature has a GUID of the form com.example:feature-name.  The reversed DNS name
     ensures that the feature's GUID is unique across all ZFS implementations.  When unsupported
     features are encountered on a pool they will be identified by their GUIDs.  Refer to the
     documentation for the ZFS implementation that created the pool for information about those
     features.

     Each supported feature also has a short name.  By convention a feature's short name is the
     portion of its GUID which follows the ‘:’ (i.e.  com.example:feature-name would have the
     short name feature-name), however a feature's short name may differ across ZFS
     implementations if following the convention would result in name conflicts.

   Feature states
     Features can be in one of three states:

     active    This feature's on-disk format changes are in effect on the pool.  Support for this
               feature is required to import the pool in read-write mode.  If this feature is not
               read-only compatible, support is also required to import the pool in read-only
               mode (see Read-only compatibility).

     enabled   An administrator has marked this feature as enabled on the pool, but the feature's
               on-disk format changes have not been made yet.  The pool can still be imported by
               software that does not support this feature, but changes may be made to the on-
               disk format at any time which will move the feature to the active state.  Some
               features may support returning to the enabled state after becoming active.  See
               feature-specific documentation for details.

     disabled  This feature's on-disk format changes have not been made and will not be made
               unless an administrator moves the feature to the enabled state.  Features cannot
               be disabled once they have been enabled.

     The state of supported features is exposed through pool properties of the form
     feature@short-name.

   Read-only compatibility
     Some features may make on-disk format changes that do not interfere with other software's
     ability to read from the pool.  These features are referred to as “read-only compatible”.
     If all unsupported features on a pool are read-only compatible, the pool can be imported in
     read-only mode by setting the readonly property during import (see zpool-import(8) for
     details on importing pools).

   Unsupported features
     For each unsupported feature enabled on an imported pool, a pool property named
     unsupported@feature-name will indicate why the import was allowed despite the unsupported
     feature.  Possible values for this property are:

     inactive  The feature is in the enabled state and therefore the pool's on-disk format is
               still compatible with software that does not support this feature.

     readonly  The feature is read-only compatible and the pool has been imported in read-only
               mode.

   Feature dependencies
     Some features depend on other features being enabled in order to function.  Enabling a
     feature will automatically enable any features it depends on.

   Compatibility feature sets
     It is sometimes necessary for a pool to maintain compatibility with a specific on-disk
     format, by enabling and disabling particular features.  The compatibility feature
     facilitates this by allowing feature sets to be read from text files.  When set to off (the
     default), compatibility feature sets are disabled (i.e. all features are enabled); when set
     to legacy, no features are enabled.  When set to a comma-separated list of filenames (each
     filename may either be an absolute path, or relative to /etc/zfs/compatibility.d or
     /usr/share/zfs/compatibility.d), the lists of requested features are read from those files,
     separated by whitespace and/or commas.  Only features present in all files are enabled.

     Simple sanity checks are applied to the files: they must be between 1B and 16kB in size, and
     must end with a newline character.

     The requested features are applied when a pool is created using zpool create -o
     compatibility= and controls which features are enabled when using zpool upgrade.  zpool
     status will not show a warning about disabled features which are not part of the requested
     feature set.

     The special value legacy prevents any features from being enabled, either via zpool upgrade
     or zpool set feature@feature-name=enabled.  This setting also prevents pools from being
     upgraded to newer on-disk versions.  This is a safety measure to prevent new features from
     being accidentally enabled, breaking compatibility.

     By convention, compatibility files in /usr/share/zfs/compatibility.d are provided by the
     distribution, and include feature sets supported by important versions of popular
     distributions, and feature sets commonly supported at the start of each year.  Compatibility
     files in /etc/zfs/compatibility.d, if present, will take precedence over files with the same
     name in /usr/share/zfs/compatibility.d.

     If an unrecognized feature is found in these files, an error message will be shown.  If the
     unrecognized feature is in a file in /etc/zfs/compatibility.d, this is treated as an error
     and processing will stop.  If the unrecognized feature is under
     /usr/share/zfs/compatibility.d, this is treated as a warning and processing will continue.
     This difference is to allow distributions to include features which might not be recognized
     by the currently-installed binaries.

     Compatibility files may include comments: any text from ‘#’ to the end of the line is
     ignored.

     Example:
         example# cat /usr/share/zfs/compatibility.d/grub2
         # Features which are supported by GRUB2
         async_destroy
         bookmarks
         embedded_data
         empty_bpobj
         enabled_txg
         extensible_dataset
         filesystem_limits
         hole_birth
         large_blocks
         lz4_compress
         spacemap_histogram

         example# zpool create -o compatibility=grub2 bootpool vdev

     See zpool-create(8) and zpool-upgrade(8) for more information on how these commands are
     affected by feature sets.

FEATURES

     The following features are supported on this system:

     allocation_classes
             GUID                  org.zfsonlinux:allocation_classes
             READ-ONLY COMPATIBLE  yes

             This feature enables support for separate allocation classes.

             This feature becomes active when a dedicated allocation class vdev (dedup or
             special) is created with the zpool create or zpool add commands.  With device
             removal, it can be returned to the enabled state if all the dedicated allocation
             class vdevs are removed.

     async_destroy
             GUID                  com.delphix:async_destroy
             READ-ONLY COMPATIBLE  yes

             Destroying a file system requires traversing all of its data in order to return its
             used space to the pool.  Without async_destroy, the file system is not fully removed
             until all space has been reclaimed.  If the destroy operation is interrupted by a
             reboot or power outage, the next attempt to open the pool will need to complete the
             destroy operation synchronously.

             When async_destroy is enabled, the file system's data will be reclaimed by a
             background process, allowing the destroy operation to complete without traversing
             the entire file system.  The background process is able to resume interrupted
             destroys after the pool has been opened, eliminating the need to finish interrupted
             destroys as part of the open operation.  The amount of space remaining to be
             reclaimed by the background process is available through the freeing property.

             This feature is only active while freeing is non-zero.

     bookmarks
             GUID                  com.delphix:bookmarks
             DEPENDENCIES          extensible_dataset
             READ-ONLY COMPATIBLE  yes

             This feature enables use of the zfs bookmark command.

             This feature is active while any bookmarks exist in the pool.  All bookmarks in the
             pool can be listed by running zfs list -t bookmark -r poolname.

     bookmark_v2
             GUID                  com.datto:bookmark_v2
             DEPENDENCIES          bookmark, extensible_dataset
             READ-ONLY COMPATIBLE  no

             This feature enables the creation and management of larger bookmarks which are
             needed for other features in ZFS.

             This feature becomes active when a v2 bookmark is created and will be returned to
             the enabled state when all v2 bookmarks are destroyed.

     bookmark_written
             GUID                  com.delphix:bookmark_written
             DEPENDENCIES          bookmark, extensible_dataset, bookmark_v2
             READ-ONLY COMPATIBLE  no

             This feature enables additional bookmark accounting fields, enabling the
             written#bookmark property (space written since a bookmark) and estimates of send
             stream sizes for incrementals from bookmarks.

             This feature becomes active when a bookmark is created and will be returned to the
             enabled state when all bookmarks with these fields are destroyed.

     device_rebuild
             GUID                  org.openzfs:device_rebuild
             READ-ONLY COMPATIBLE  yes

             This feature enables the ability for the zpool attach and zpool replace commands to
             perform sequential reconstruction (instead of healing reconstruction) when
             resilvering.

             Sequential reconstruction resilvers a device in LBA order without immediately
             verifying the checksums.  Once complete, a scrub is started, which then verifies the
             checksums.  This approach allows full redundancy to be restored to the pool in the
             minimum amount of time.  This two-phase approach will take longer than a healing
             resilver when the time to verify the checksums is included.  However, unless there
             is additional pool damage, no checksum errors should be reported by the scrub.  This
             feature is incompatible with raidz configurations.  This feature becomes active
             while a sequential resilver is in progress, and returns to enabled when the resilver
             completes.

     device_removal
             GUID                  com.delphix:device_removal
             READ-ONLY COMPATIBLE  no

             This feature enables the zpool remove command to remove top-level vdevs, evacuating
             them to reduce the total size of the pool.

             This feature becomes active when the zpool remove command is used on a top-level
             vdev, and will never return to being enabled.

     draid
             GUID                  org.openzfs:draid
             READ-ONLY COMPATIBLE  no

             This feature enables use of the draid vdev type.  dRAID is a variant of raidz which
             provides integrated distributed hot spares that allow faster resilvering while
             retaining the benefits of raidz.  Data, parity, and spare space are organized in
             redundancy groups and distributed evenly over all of the devices.

             This feature becomes active when creating a pool which uses the draid vdev type, or
             when adding a new draid vdev to an existing pool.

     edonr
             GUID                  org.illumos:edonr
             DEPENDENCIES          extensible_dataset
             READ-ONLY COMPATIBLE  no

             This feature enables the use of the Edon-R hash algorithm for checksum, including
             for nopwrite (if compression is also enabled, an overwrite of a block whose checksum
             matches the data being written will be ignored).  In an abundance of caution, Edon-R
             requires verification when used with dedup: zfs set dedup=edonr,verify (see
             zfs-set(8)).

             Edon-R is a very high-performance hash algorithm that was part of the NIST SHA-3
             competition.  It provides extremely high hash performance (over 350% faster than
             SHA-256), but was not selected because of its unsuitability as a general purpose
             secure hash algorithm.  This implementation utilizes the new salted checksumming
             functionality in ZFS, which means that the checksum is pre-seeded with a secret
             256-bit random key (stored on the pool) before being fed the data block to be
             checksummed.  Thus the produced checksums are unique to a given pool, preventing
             hash collision attacks on systems with dedup.

             When the edonr feature is set to enabled, the administrator can turn on the edonr
             checksum on any dataset using zfs set checksum=edonr dset (see zfs-set(8)).  This
             feature becomes active once a checksum property has been set to edonr, and will
             return to being enabled once all filesystems that have ever had their checksum set
             to edonr are destroyed.

             FreeBSD does not support the edonr feature.

     embedded_data
             GUID                  com.delphix:embedded_data
             READ-ONLY COMPATIBLE  no

             This feature improves the performance and compression ratio of highly-compressible
             blocks.  Blocks whose contents can compress to 112 bytes or smaller can take
             advantage of this feature.

             When this feature is enabled, the contents of highly-compressible blocks are stored
             in the block "pointer" itself (a misnomer in this case, as it contains the
             compressed data, rather than a pointer to its location on disk).  Thus the space of
             the block (one sector, typically 512B or 4kB) is saved, and no additional I/O is
             needed to read and write the data block.  This feature becomes active as soon as it
             is enabled and will never return to being enabled.

     empty_bpobj
             GUID                  com.delphix:empty_bpobj
             READ-ONLY COMPATIBLE  yes

             This feature increases the performance of creating and using a large number of
             snapshots of a single filesystem or volume, and also reduces the disk space
             required.

             When there are many snapshots, each snapshot uses many Block Pointer Objects
             (bpobjs) to track blocks associated with that snapshot.  However, in common use
             cases, most of these bpobjs are empty.  This feature allows us to create each bpobj
             on-demand, thus eliminating the empty bpobjs.

             This feature is active while there are any filesystems, volumes, or snapshots which
             were created after enabling this feature.

     enabled_txg
             GUID                  com.delphix:enabled_txg
             READ-ONLY COMPATIBLE  yes

             Once this feature is enabled, ZFS records the transaction group number in which new
             features are enabled.  This has no user-visible impact, but other features may
             depend on this feature.

             This feature becomes active
              as soon as it is enabled and will never return to being enabled.

     encryption
             GUID                  com.datto:encryption
             DEPENDENCIES          bookmark_v2, extensible_dataset
             READ-ONLY COMPATIBLE  no

             This feature enables the creation and management of natively encrypted datasets.

             This feature becomes active when an encrypted dataset is created and will be
             returned to the enabled state when all datasets that use this feature are destroyed.

     extensible_dataset
             GUID                  com.delphix:extensible_dataset
             READ-ONLY COMPATIBLE  no

             This feature allows more flexible use of internal ZFS data structures, and exists
             for other features to depend on.

             This feature will be active when the first dependent feature uses it, and will be
             returned to the enabled state when all datasets that use this feature are destroyed.

     filesystem_limits
             GUID                  com.joyent:filesystem_limits
             DEPENDENCIES          extensible_dataset
             READ-ONLY COMPATIBLE  yes

             This feature enables filesystem and snapshot limits.  These limits can be used to
             control how many filesystems and/or snapshots can be created at the point in the
             tree on which the limits are set.

             This feature is active once either of the limit properties has been set on a
             dataset.  Once activated the feature is never deactivated.

     hole_birth
             GUID                  com.delphix:hole_birth
             DEPENDENCIES          enabled_txg
             READ-ONLY COMPATIBLE  no

             This feature has/had bugs, the result of which is that, if you do a zfs send -i (or
             -R, since it uses -i) from an affected dataset, the receiving party will not see any
             checksum or other errors, but the resulting destination snapshot will not match the
             source.  Its use by zfs send -i has been disabled by default (see
             send_holes_without_birth_time in zfs(4)).

             This feature improves performance of incremental sends (zfs send -i) and receives
             for objects with many holes.  The most common case of hole-filled objects is zvols.

             An incremental send stream from snapshot A to snapshot B contains information about
             every block that changed between A and B.  Blocks which did not change between those
             snapshots can be identified and omitted from the stream using a piece of metadata
             called the "block birth time", but birth times are not recorded for holes (blocks
             filled only with zeroes).  Since holes created after A cannot be distinguished from
             holes created before A, information about every hole in the entire filesystem or
             zvol is included in the send stream.

             For workloads where holes are rare this is not a problem.  However, when
             incrementally replicating filesystems or zvols with many holes (for example a zvol
             formatted with another filesystem) a lot of time will be spent sending and receiving
             unnecessary information about holes that already exist on the receiving side.

             Once the hole_birth feature has been enabled the block birth times of all new holes
             will be recorded.  Incremental sends between snapshots created after this feature is
             enabled will use this new metadata to avoid sending information about holes that
             already exist on the receiving side.

             This feature becomes active as soon as it is enabled and will never return to being
             enabled.

     large_blocks
             GUID                  org.open-zfs:large_blocks
             DEPENDENCIES          extensible_dataset
             READ-ONLY COMPATIBLE  no

             This feature allows the record size on a dataset to be set larger than 128kB.

             This feature becomes active once a dataset contains a file with a block size larger
             than 128kB, and will return to being enabled once all filesystems that have ever had
             their recordsize larger than 128kB are destroyed.

     large_dnode
             GUID                  org.zfsonlinux:large_dnode
             DEPENDENCIES          extensible_dataset
             READ-ONLY COMPATIBLE  no

             This feature allows the size of dnodes in a dataset to be set larger than 512B.
             This feature becomes active once a dataset contains an object with a dnode larger
             than 512B, which occurs as a result of setting the dnodesize dataset property to a
             value other than legacy.  The feature will return to being enabled once all
             filesystems that have ever contained a dnode larger than 512B are destroyed.  Large
             dnodes allow more data to be stored in the bonus buffer, thus potentially improving
             performance by avoiding the use of spill blocks.

     livelist
             GUID                  com.delphix:livelist
             READ-ONLY COMPATIBLE  yes

             This feature allows clones to be deleted faster than the traditional method when a
             large number of random/sparse writes have been made to the clone.  All blocks
             allocated and freed after a clone is created are tracked by the the clone's livelist
             which is referenced during the deletion of the clone.  The feature is activated when
             a clone is created and remains active until all clones have been destroyed.

     log_spacemap
             GUID                  com.delphix:log_spacemap
             DEPENDENCIES          com.delphix:spacemap_v2
             READ-ONLY COMPATIBLE  yes

             This feature improves performance for heavily-fragmented pools, especially when
             workloads are heavy in random-writes.  It does so by logging all the metaslab
             changes on a single spacemap every TXG instead of scattering multiple writes to all
             the metaslab spacemaps.

             This feature becomes active as soon as it is enabled and will never return to being
             enabled.

     lz4_compress
             GUID                  org.illumos:lz4_compress
             READ-ONLY COMPATIBLE  no

             lz4 is a high-performance real-time compression algorithm that features
             significantly faster compression and decompression as well as a higher compression
             ratio than the older lzjb compression.  Typically, lz4 compression is approximately
             50% faster on compressible data and 200% faster on incompressible data than lzjb.
             It is also approximately 80% faster on decompression, while giving approximately a
             10% better compression ratio.

             When the lz4_compress feature is set to enabled, the administrator can turn on lz4
             compression on any dataset on the pool using the zfs-set(8) command.  All newly
             written metadata will be compressed with the lz4 algorithm.

             This feature becomes active as soon as it is enabled and will never return to being
             enabled.

     multi_vdev_crash_dump
             GUID                  com.joyent:multi_vdev_crash_dump
             READ-ONLY COMPATIBLE  no

             This feature allows a dump device to be configured with a pool comprised of multiple
             vdevs.  Those vdevs may be arranged in any mirrored or raidz configuration.

             When the multi_vdev_crash_dump feature is set to enabled, the administrator can use
             dumpadm(1M) to configure a dump device on a pool comprised of multiple vdevs.

             Under FreeBSD and Linux this feature is unused, but registered for compatibility.
             New pools created on these systems will have the feature enabled but will never
             transition to active, as this functionality is not required for crash dump support.
             Existing pools where this feature is active can be imported.

     obsolete_counts
             GUID                  com.delphix:obsolete_counts
             DEPENDENCIES          device_removal
             READ-ONLY COMPATIBLE  yes

             This feature is an enhancement of device_removal, which will over time reduce the
             memory used to track removed devices.  When indirect blocks are freed or remapped,
             we note that their part of the indirect mapping is "obsolete" – no longer needed.

             This feature becomes active when the zpool remove command is used on a top-level
             vdev, and will never return to being enabled.

     project_quota
             GUID                  org.zfsonlinux:project_quota
             DEPENDENCIES          extensible_dataset
             READ-ONLY COMPATIBLE  yes

             This feature allows administrators to account the spaces and objects usage
             information against the project identifier (ID).

             The project ID is an object-based attribute.  When upgrading an existing filesystem,
             objects without a project ID will be assigned a zero project ID.  When this feature
             is enabled, newly created objects inherit their parent directories' project ID if
             the parent's inherit flag is set (via chattr [+-]P or zfs project -s|-C).
             Otherwise, the new object's project ID will be zero.  An object's project ID can be
             changed at any time by the owner (or privileged user) via chattr -p prjid or zfs
             project -p prjid.

             This feature will become active as soon as it is enabled and will never return to
             being disabled.  Each filesystem will be upgraded automatically when remounted, or
             when a new file is created under that filesystem. The upgrade can also be triggered
             on filesystems via zfs set version=current fs. The upgrade process runs in the
             background and may take a while to complete for filesystems containing large amounts
             of files.

     redaction_bookmarks
             GUID                  com.delphix:redaction_bookmarks
             DEPENDENCIES          bookmarks, extensible_dataset
             READ-ONLY COMPATIBLE  no

             This feature enables the use of redacted zfs sends, which create redaction bookmarks
             storing the list of blocks redacted by the send that created them.  For more
             information about redacted sends, see zfs-send(8).

     redacted_datasets
             GUID                  com.delphix:redacted_datasets
             DEPENDENCIES          extensible_dataset
             READ-ONLY COMPATIBLE  no

             This feature enables the receiving of redacted zfs sendstreams. which create
             redacted datasets when received.  These datasets are missing some of their blocks,
             and so cannot be safely mounted, and their contents cannot be safely read.  For more
             information about redacted receives, see zfs-send(8).

     resilver_defer
             GUID                  com.datto:resilver_defer
             READ-ONLY COMPATIBLE  yes

             This feature allows ZFS to postpone new resilvers if an existing one is already in
             progress.  Without this feature, any new resilvers will cause the currently running
             one to be immediately restarted from the beginning.

             This feature becomes active once a resilver has been deferred, and returns to being
             enabled when the deferred resilver begins.

     sha512
             GUID                  org.illumos:sha512
             DEPENDENCIES          extensible_dataset
             READ-ONLY COMPATIBLE  no

             This feature enables the use of the SHA-512/256 truncated hash algorithm (FIPS
             180-4) for checksum and dedup.  The native 64-bit arithmetic of SHA-512 provides an
             approximate 50% performance boost over SHA-256 on 64-bit hardware and is thus a good
             minimum-change replacement candidate for systems where hash performance is
             important, but these systems cannot for whatever reason utilize the faster skein and
             edonr algorithms.

             When the sha512 feature is set to enabled, the administrator can turn on the sha512
             checksum on any dataset using zfs set checksum=sha512 dset (see zfs-set(8)).  This
             feature becomes active once a checksum property has been set to sha512, and will
             return to being enabled once all filesystems that have ever had their checksum set
             to sha512 are destroyed.

     skein
             GUID                  org.illumos:skein
             DEPENDENCIES          extensible_dataset
             READ-ONLY COMPATIBLE  no

             This feature enables the use of the Skein hash algorithm for checksum and dedup.
             Skein is a high-performance secure hash algorithm that was a finalist in the NIST
             SHA-3 competition.  It provides a very high security margin and high performance on
             64-bit hardware (80% faster than SHA-256).  This implementation also utilizes the
             new salted checksumming functionality in ZFS, which means that the checksum is pre-
             seeded with a secret 256-bit random key (stored on the pool) before being fed the
             data block to be checksummed.  Thus the produced checksums are unique to a given
             pool, preventing hash collision attacks on systems with dedup.

             When the skein feature is set to enabled, the administrator can turn on the skein
             checksum on any dataset using zfs set checksum=skein dset (see zfs-set(8)).  This
             feature becomes active once a checksum property has been set to skein, and will
             return to being enabled once all filesystems that have ever had their checksum set
             to skein are destroyed.

     spacemap_histogram
             GUID                  com.delphix:spacemap_histogram
             READ-ONLY COMPATIBLE  yes

             This features allows ZFS to maintain more information about how free space is
             organized within the pool.  If this feature is enabled, it will be activated when a
             new space map object is created, or an existing space map is upgraded to the new
             format, and never returns back to being enabled.

     spacemap_v2
             GUID                  com.delphix:spacemap_v2
             READ-ONLY COMPATIBLE  yes

             This feature enables the use of the new space map encoding which consists of two
             words (instead of one) whenever it is advantageous.  The new encoding allows space
             maps to represent large regions of space more efficiently on-disk while also
             increasing their maximum addressable offset.

             This feature becomes active once it is enabled, and never returns back to being
             enabled.

     userobj_accounting
             GUID                  org.zfsonlinux:userobj_accounting
             DEPENDENCIES          extensible_dataset
             READ-ONLY COMPATIBLE  yes

             This feature allows administrators to account the object usage information by user
             and group.

             This feature becomes active as soon as it is enabled and will never return to being
             enabled.  Each filesystem will be upgraded automatically when remounted, or when a
             new file is created under that filesystem. The upgrade can also be triggered on
             filesystems via zfs set version=current fs. The upgrade process runs in the
             background and may take a while to complete for filesystems containing large amounts
             of files.

     zpool_checkpoint
             GUID                  com.delphix:zpool_checkpoint
             READ-ONLY COMPATIBLE  yes

             This feature enables the zpool checkpoint command that can checkpoint the state of
             the pool at the time it was issued and later rewind back to it or discard it.

             This feature becomes active when the zpool checkpoint command is used to checkpoint
             the pool.  The feature will only return back to being enabled when the pool is
             rewound or the checkpoint has been discarded.

     zstd_compress
             GUID                  org.freebsd:zstd_compress
             DEPENDENCIES          extensible_dataset
             READ-ONLY COMPATIBLE  no

             zstd is a high-performance compression algorithm that features a combination of high
             compression ratios and high speed.  Compared to gzip, zstd offers slightly better
             compression at much higher speeds.  Compared to lz4, zstd offers much better
             compression while being only modestly slower.  Typically, zstd compression speed
             ranges from 250 to 500 MB/s per thread and decompression speed is over 1 GB/s per
             thread.

             When the zstd feature is set to enabled, the administrator can turn on zstd
             compression of any dataset using zfs set compress=zstd dset (see zfs-set(8)).  This
             feature becomes active once a compress property has been set to zstd, and will
             return to being enabled once all filesystems that have ever had their compress
             property set to zstd are destroyed.

SEE ALSO

     zpool(8)