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>

@@ -12,11 +12,11 @@
 .\" CDDL HEADER in each file and include the License file at
 .\" usr/src/OPENSOLARIS.LICENSE.  If applicable, add the following below this
 .\" CDDL HEADER, with the fields enclosed by brackets "[]" replaced with your
 .\" own identifying information:
 .\" Portions Copyright [yyyy] [name of copyright owner]
-.TH ZPOOL-FEATURES 5 "Mar 16, 2012"
+.TH ZPOOL-FEATURES 5 "Aug 27, 2013"
 .SH NAME
 zpool\-features \- ZFS pool feature descriptions
 .SH DESCRIPTION
 .sp
 .LP

@@ -227,11 +227,30 @@
 pool (even before any data is written). Since this feature is not
 read-only compatible, this operation will render the pool unimportable
 on systems without support for the \fBlz4_compress\fR feature. At the
 moment, this operation cannot be reversed. Booting off of
 \fBlz4\fR-compressed root pools is supported.
+.RE
 
+.sp
+.ne 2
+.na
+\fB\fBspacemap_histogram\fR\fR
+.ad
+.RS 4n
+.TS
+l l .
+GUID    com.delphix:spacemap_histogram
+READ\-ONLY COMPATIBLE   yes
+DEPENDENCIES    none
+.TE
+
+This features allows ZFS to maintain more information about how free space
+is organized within the pool. If this feature is \fBenabled\fR, ZFS will
+set this feature to \fBactive\fR when a new space map object is created or
+an existing space map is upgraded to the new format. Once the feature is
+\fBactive\fR, it will remain in that state until the pool is destroyed.
 .RE
 
 .sp
 .ne 2
 .na