Print this page
OS-1566 dataset quota for ZFS datasets
| Split |
Close |
| Expand all |
| Collapse all |
--- old/usr/src/man/man5/zpool-features.5
+++ new/usr/src/man/man5/zpool-features.5
1 1 '\" te
2 2 .\" Copyright (c) 2012 by Delphix. All rights reserved.
3 +.\" Copyright (c) 2012 Joyent, Inc. All rights reserved.
3 4 .\" The contents of this file are subject to the terms of the Common Development
4 5 .\" and Distribution License (the "License"). You may not use this file except
5 6 .\" in compliance with the License. You can obtain a copy of the license at
6 7 .\" usr/src/OPENSOLARIS.LICENSE or http://www.opensolaris.org/os/licensing.
7 8 .\"
8 9 .\" See the License for the specific language governing permissions and
9 10 .\" limitations under the License. When distributing Covered Code, include this
10 11 .\" CDDL HEADER in each file and include the License file at
11 12 .\" usr/src/OPENSOLARIS.LICENSE. If applicable, add the following below this
12 13 .\" CDDL HEADER, with the fields enclosed by brackets "[]" replaced with your
13 14 .\" own identifying information:
14 15 .\" Portions Copyright [yyyy] [name of copyright owner]
15 -.TH ZPOOL-FEATURES 5 "Mar 16, 2012"
16 +.TH ZPOOL-FEATURES 5 "Oct 24, 2012"
16 17 .SH NAME
17 18 zpool\-features \- ZFS pool feature descriptions
18 19 .SH DESCRIPTION
19 20 .sp
20 21 .LP
21 22 ZFS pool on\-disk format versions are specified via "features" which replace
22 23 the old on\-disk format numbers (the last supported on\-disk format number is
23 24 28). To enable a feature on a pool use the \fBupgrade\fR subcommand of the
24 25 \fBzpool\fR(1M) command, or set the \fBfeature@\fR\fIfeature_name\fR property
25 26 to \fBenabled\fR.
26 27 .sp
27 28 .LP
28 29 The pool format does not affect file system version compatibility or the ability
29 30 to send file systems between pools.
30 31 .sp
31 32 .LP
32 33 Since most features can be enabled independently of each other the on\-disk
33 34 format of the pool is specified by the set of all features marked as
34 35 \fBactive\fR on the pool. If the pool was created by another software version
35 36 this set may include unsupported features.
36 37 .SS "Identifying features"
37 38 .sp
38 39 .LP
39 40 Every feature has a guid of the form \fIcom.example:feature_name\fR. The reverse
40 41 DNS name ensures that the feature's guid is unique across all ZFS
41 42 implementations. When unsupported features are encountered on a pool they will
42 43 be identified by their guids. Refer to the documentation for the ZFS
43 44 implementation that created the pool for information about those features.
44 45 .sp
45 46 .LP
46 47 Each supported feature also has a short name. By convention a feature's short
47 48 name is the portion of its guid which follows the ':' (e.g.
48 49 \fIcom.example:feature_name\fR would have the short name \fIfeature_name\fR),
49 50 however a feature's short name may differ across ZFS implementations if
50 51 following the convention would result in name conflicts.
51 52 .SS "Feature states"
52 53 .sp
53 54 .LP
54 55 Features can be in one of three states:
55 56 .sp
56 57 .ne 2
57 58 .na
58 59 \fB\fBactive\fR\fR
59 60 .ad
60 61 .RS 12n
61 62 This feature's on\-disk format changes are in effect on the pool. Support for
62 63 this feature is required to import the pool in read\-write mode. If this
63 64 feature is not read-only compatible, support is also required to import the pool
64 65 in read\-only mode (see "Read\-only compatibility").
65 66 .RE
66 67
67 68 .sp
68 69 .ne 2
69 70 .na
70 71 \fB\fBenabled\fR\fR
71 72 .ad
72 73 .RS 12n
73 74 An administrator has marked this feature as enabled on the pool, but the
74 75 feature's on\-disk format changes have not been made yet. The pool can still be
75 76 imported by software that does not support this feature, but changes may be made
76 77 to the on\-disk format at any time which will move the feature to the
77 78 \fBactive\fR state. Some features may support returning to the \fBenabled\fR
78 79 state after becoming \fBactive\fR. See feature\-specific documentation for
79 80 details.
80 81 .RE
81 82
82 83 .sp
83 84 .ne 2
84 85 .na
85 86 \fBdisabled\fR
86 87 .ad
87 88 .RS 12n
88 89 This feature's on\-disk format changes have not been made and will not be made
89 90 unless an administrator moves the feature to the \fBenabled\fR state. Features
90 91 cannot be disabled once they have been enabled.
91 92 .RE
92 93
93 94 .sp
94 95 .LP
95 96 The state of supported features is exposed through pool properties of the form
96 97 \fIfeature@short_name\fR.
97 98 .SS "Read\-only compatibility"
98 99 .sp
99 100 .LP
100 101 Some features may make on\-disk format changes that do not interfere with other
101 102 software's ability to read from the pool. These features are referred to as
102 103 "read\-only compatible". If all unsupported features on a pool are read\-only
103 104 compatible, the pool can be imported in read\-only mode by setting the
104 105 \fBreadonly\fR property during import (see \fBzpool\fR(1M) for details on
105 106 importing pools).
106 107 .SS "Unsupported features"
107 108 .sp
108 109 .LP
109 110 For each unsupported feature enabled on an imported pool a pool property
110 111 named \fIunsupported@feature_guid\fR will indicate why the import was allowed
111 112 despite the unsupported feature. Possible values for this property are:
112 113
113 114 .sp
114 115 .ne 2
115 116 .na
116 117 \fB\fBinactive\fR\fR
117 118 .ad
118 119 .RS 12n
119 120 The feature is in the \fBenabled\fR state and therefore the pool's on\-disk
120 121 format is still compatible with software that does not support this feature.
121 122 .RE
122 123
123 124 .sp
124 125 .ne 2
125 126 .na
126 127 \fB\fBreadonly\fR\fR
127 128 .ad
128 129 .RS 12n
129 130 The feature is read\-only compatible and the pool has been imported in
130 131 read\-only mode.
131 132 .RE
132 133
133 134 .SS "Feature dependencies"
134 135 .sp
135 136 .LP
136 137 Some features depend on other features being enabled in order to function
137 138 properly. Enabling a feature will automatically enable any features it
138 139 depends on.
139 140 .SH FEATURES
140 141 .sp
141 142 .LP
142 143 The following features are supported on this system:
143 144 .sp
144 145 .ne 2
145 146 .na
146 147 \fB\fBasync_destroy\fR\fR
147 148 .ad
148 149 .RS 4n
149 150 .TS
150 151 l l .
151 152 GUID com.delphix:async_destroy
152 153 READ\-ONLY COMPATIBLE yes
153 154 DEPENDENCIES none
154 155 .TE
155 156
156 157 Destroying a file system requires traversing all of its data in order to
157 158 return its used space to the pool. Without \fBasync_destroy\fR the file system
158 159 is not fully removed until all space has been reclaimed. If the destroy
159 160 operation is interrupted by a reboot or power outage the next attempt to open
160 161 the pool will need to complete the destroy operation synchronously.
161 162
162 163 When \fBasync_destroy\fR is enabled the file system's data will be reclaimed
|
↓ open down ↓ |
137 lines elided |
↑ open up ↑ |
163 164 by a background process, allowing the destroy operation to complete without
164 165 traversing the entire file system. The background process is able to resume
165 166 interrupted destroys after the pool has been opened, eliminating the need
166 167 to finish interrupted destroys as part of the open operation. The amount
167 168 of space remaining to be reclaimed by the background process is available
168 169 through the \fBfreeing\fR property.
169 170
170 171 This feature is only \fBactive\fR while \fBfreeing\fR is non\-zero.
171 172 .RE
172 173
174 +.sp
175 +.ne 2
176 +.na
177 +\fB\fBdataset_quota\fR\fR
178 +.ad
179 +.RS 4n
180 +.TS
181 +l l .
182 +GUID com.joyent:dataset_quota
183 +READ\-ONLY COMPATIBLE yes
184 +DEPENDENCIES none
185 +.TE
186 +
187 +This feature enables dataset quotas and snapshot quotas. These quotas
188 +can be used to limit how many datasets and/or snapshots can be created
189 +under the dataset on which the quotas are set.
190 +
191 +This feature is \fBactive\fR once either of the quota properties has been
192 +set on a dataset.
193 +.RE
194 +
173 195 .sp
174 196 .ne 2
175 197 .na
176 198 \fB\fBempty_bpobj\fR\fR
177 199 .ad
178 200 .RS 4n
179 201 .TS
180 202 l l .
181 203 GUID com.delphix:empty_bpobj
182 204 READ\-ONLY COMPATIBLE yes
183 205 DEPENDENCIES none
184 206 .TE
185 207
186 208 This feature increases the performance of creating and using a large
187 209 number of snapshots of a single filesystem or volume, and also reduces
188 210 the disk space required.
189 211
190 212 When there are many snapshots, each snapshot uses many Block Pointer
191 213 Objects (bpobj's) to track blocks associated with that snapshot.
192 214 However, in common use cases, most of these bpobj's are empty. This
193 215 feature allows us to create each bpobj on-demand, thus eliminating the
194 216 empty bpobjs.
195 217
196 218 This feature is \fBactive\fR while there are any filesystems, volumes,
197 219 or snapshots which were created after enabling this feature.
198 220 .RE
199 221
200 222 .SH "SEE ALSO"
201 223 \fBzpool\fR(1M)
|
↓ open down ↓ |
19 lines elided |
↑ open up ↑ |
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX