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4101 metaslab_debug should allow for fine-grained control
4102 space_maps should store more information about themselves
4103 space map object blocksize should be increased
4104 ::spa_space no longer works
4105 removing a mirrored log device results in a leaked object
4106 asynchronously load metaslab
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Adam Leventhal <ahl@delphix.com>
Reviewed by: Sebastien Roy <seb@delphix.com>
   1 '\" te
   2 .\" Copyright (c) 2012 by Delphix. All rights reserved.
   3 .\" Copyright (c) 2013 by Saso Kiselkov. All rights reserved.
   4 .\" Copyright (c) 2013, Joyent, Inc. All rights reserved.
   5 .\" The contents of this file are subject to the terms of the Common Development
   6 .\" and Distribution License (the "License").  You may not use this file except
   7 .\" in compliance with the License. You can obtain a copy of the license at
   8 .\" usr/src/OPENSOLARIS.LICENSE or http://www.opensolaris.org/os/licensing.
   9 .\"
  10 .\" See the License for the specific language governing permissions and
  11 .\" limitations under the License. When distributing Covered Code, include this
  12 .\" CDDL HEADER in each file and include the License file at
  13 .\" usr/src/OPENSOLARIS.LICENSE.  If applicable, add the following below this
  14 .\" CDDL HEADER, with the fields enclosed by brackets "[]" replaced with your
  15 .\" own identifying information:
  16 .\" Portions Copyright [yyyy] [name of copyright owner]
  17 .TH ZPOOL-FEATURES 5 "Mar 16, 2012"
  18 .SH NAME
  19 zpool\-features \- ZFS pool feature descriptions
  20 .SH DESCRIPTION
  21 .sp
  22 .LP
  23 ZFS pool on\-disk format versions are specified via "features" which replace
  24 the old on\-disk format numbers (the last supported on\-disk format number is
  25 28). To enable a feature on a pool use the \fBupgrade\fR subcommand of the
  26 \fBzpool\fR(1M) command, or set the \fBfeature@\fR\fIfeature_name\fR property
  27 to \fBenabled\fR.
  28 .sp
  29 .LP
  30 The pool format does not affect file system version compatibility or the ability
  31 to send file systems between pools.
  32 .sp
  33 .LP
  34 Since most features can be enabled independently of each other the on\-disk
  35 format of the pool is specified by the set of all features marked as
  36 \fBactive\fR on the pool. If the pool was created by another software version
  37 this set may include unsupported features.


 212 DEPENDENCIES    none
 213 .TE
 214 
 215 \fBlz4\fR is a high-performance real-time compression algorithm that
 216 features significantly faster compression and decompression as well as a
 217 higher compression ratio than the older \fBlzjb\fR compression.
 218 Typically, \fBlz4\fR compression is approximately 50% faster on
 219 compressible data and 200% faster on incompressible data than
 220 \fBlzjb\fR. It is also approximately 80% faster on decompression, while
 221 giving approximately 10% better compression ratio.
 222 
 223 When the \fBlz4_compress\fR feature is set to \fBenabled\fR, the
 224 administrator can turn on \fBlz4\fR compression on any dataset on the
 225 pool using the \fBzfs\fR(1M) command. Please note that doing so will
 226 immediately activate the \fBlz4_compress\fR feature on the underlying
 227 pool (even before any data is written). Since this feature is not
 228 read-only compatible, this operation will render the pool unimportable
 229 on systems without support for the \fBlz4_compress\fR feature. At the
 230 moment, this operation cannot be reversed. Booting off of
 231 \fBlz4\fR-compressed root pools is supported.

 232 


















 233 .RE
 234 
 235 .sp
 236 .ne 2
 237 .na
 238 \fB\fBmulti_vdev_crash_dump\fR\fR
 239 .ad
 240 .RS 4n
 241 .TS
 242 l l .
 243 GUID    com.joyent:multi_vdev_crash_dump
 244 READ\-ONLY COMPATIBLE   no
 245 DEPENDENCIES    none
 246 .TE
 247 
 248 This feature allows a dump device to be configured with a pool comprised
 249 of multiple vdevs.  Those vdevs may be arranged in any mirrored or raidz
 250 configuration.
 251 
 252 When the \fBmulti_vdev_crash_dump\fR feature is set to \fBenabled\fR,
   1 '\" te
   2 .\" Copyright (c) 2012 by Delphix. All rights reserved.
   3 .\" Copyright (c) 2013 by Saso Kiselkov. All rights reserved.
   4 .\" Copyright (c) 2013, Joyent, Inc. All rights reserved.
   5 .\" The contents of this file are subject to the terms of the Common Development
   6 .\" and Distribution License (the "License").  You may not use this file except
   7 .\" in compliance with the License. You can obtain a copy of the license at
   8 .\" usr/src/OPENSOLARIS.LICENSE or http://www.opensolaris.org/os/licensing.
   9 .\"
  10 .\" See the License for the specific language governing permissions and
  11 .\" limitations under the License. When distributing Covered Code, include this
  12 .\" CDDL HEADER in each file and include the License file at
  13 .\" usr/src/OPENSOLARIS.LICENSE.  If applicable, add the following below this
  14 .\" CDDL HEADER, with the fields enclosed by brackets "[]" replaced with your
  15 .\" own identifying information:
  16 .\" Portions Copyright [yyyy] [name of copyright owner]
  17 .TH ZPOOL-FEATURES 5 "Aug 27, 2013"
  18 .SH NAME
  19 zpool\-features \- ZFS pool feature descriptions
  20 .SH DESCRIPTION
  21 .sp
  22 .LP
  23 ZFS pool on\-disk format versions are specified via "features" which replace
  24 the old on\-disk format numbers (the last supported on\-disk format number is
  25 28). To enable a feature on a pool use the \fBupgrade\fR subcommand of the
  26 \fBzpool\fR(1M) command, or set the \fBfeature@\fR\fIfeature_name\fR property
  27 to \fBenabled\fR.
  28 .sp
  29 .LP
  30 The pool format does not affect file system version compatibility or the ability
  31 to send file systems between pools.
  32 .sp
  33 .LP
  34 Since most features can be enabled independently of each other the on\-disk
  35 format of the pool is specified by the set of all features marked as
  36 \fBactive\fR on the pool. If the pool was created by another software version
  37 this set may include unsupported features.


 212 DEPENDENCIES    none
 213 .TE
 214 
 215 \fBlz4\fR is a high-performance real-time compression algorithm that
 216 features significantly faster compression and decompression as well as a
 217 higher compression ratio than the older \fBlzjb\fR compression.
 218 Typically, \fBlz4\fR compression is approximately 50% faster on
 219 compressible data and 200% faster on incompressible data than
 220 \fBlzjb\fR. It is also approximately 80% faster on decompression, while
 221 giving approximately 10% better compression ratio.
 222 
 223 When the \fBlz4_compress\fR feature is set to \fBenabled\fR, the
 224 administrator can turn on \fBlz4\fR compression on any dataset on the
 225 pool using the \fBzfs\fR(1M) command. Please note that doing so will
 226 immediately activate the \fBlz4_compress\fR feature on the underlying
 227 pool (even before any data is written). Since this feature is not
 228 read-only compatible, this operation will render the pool unimportable
 229 on systems without support for the \fBlz4_compress\fR feature. At the
 230 moment, this operation cannot be reversed. Booting off of
 231 \fBlz4\fR-compressed root pools is supported.
 232 .RE
 233 
 234 .sp
 235 .ne 2
 236 .na
 237 \fB\fBspacemap_histogram\fR\fR
 238 .ad
 239 .RS 4n
 240 .TS
 241 l l .
 242 GUID    com.delphix:spacemap_histogram
 243 READ\-ONLY COMPATIBLE   yes
 244 DEPENDENCIES    none
 245 .TE
 246 
 247 This features allows ZFS to maintain more information about how free space
 248 is organized within the pool. If this feature is \fBenabled\fR, ZFS will
 249 set this feature to \fBactive\fR when a new space map object is created or
 250 an existing space map is upgraded to the new format. Once the feature is
 251 \fBactive\fR, it will remain in that state until the pool is destroyed.
 252 .RE
 253 
 254 .sp
 255 .ne 2
 256 .na
 257 \fB\fBmulti_vdev_crash_dump\fR\fR
 258 .ad
 259 .RS 4n
 260 .TS
 261 l l .
 262 GUID    com.joyent:multi_vdev_crash_dump
 263 READ\-ONLY COMPATIBLE   no
 264 DEPENDENCIES    none
 265 .TE
 266 
 267 This feature allows a dump device to be configured with a pool comprised
 268 of multiple vdevs.  Those vdevs may be arranged in any mirrored or raidz
 269 configuration.
 270 
 271 When the \fBmulti_vdev_crash_dump\fR feature is set to \fBenabled\fR,