1.\" Copyright (c) 2007 The DragonFly Project. All rights reserved. 2.\" 3.\" This code is derived from software contributed to The DragonFly Project 4.\" by Matthew Dillon <dillon@backplane.com> 5.\" 6.\" Redistribution and use in source and binary forms, with or without 7.\" modification, are permitted provided that the following conditions 8.\" are met: 9.\" 10.\" 1. Redistributions of source code must retain the above copyright 11.\" notice, this list of conditions and the following disclaimer. 12.\" 2. Redistributions in binary form must reproduce the above copyright 13.\" notice, this list of conditions and the following disclaimer in 14.\" the documentation and/or other materials provided with the 15.\" distribution. 16.\" 3. Neither the name of The DragonFly Project nor the names of its 17.\" contributors may be used to endorse or promote products derived 18.\" from this software without specific, prior written permission. 19.\" 20.\" THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 21.\" ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 22.\" LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 23.\" FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 24.\" COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 25.\" INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING, 26.\" BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 27.\" LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 28.\" AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 29.\" OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 30.\" OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31.\" SUCH DAMAGE. 32.\" 33.Dd October 7, 2011 34.Dt NEWFS_HAMMER 8 35.Os 36.Sh NAME 37.Nm newfs_hammer 38.Nd construct a new HAMMER file system 39.Sh SYNOPSIS 40.Nm 41.Fl L Ar label 42.Op Fl \&Ef 43.Op Fl b Ar bootsize 44.Op Fl m Ar savesize 45.Op Fl u Ar undosize 46.Op Fl V Ar version 47.Ar special ... 48.Sh DESCRIPTION 49The 50.Nm 51utility creates a 52.Nm HAMMER 53file system on device(s) 54.Ar special . 55If multiple devices are specified a single 56.Nm HAMMER 57file system is created 58which spans all of them. 59Each 60.Ar special 61will constitute a volume which the 62.Nm HAMMER 63file system is built on. 64.Nm HAMMER 65file systems are sector-size agnostic, however the 66.Dx 67implementation requires the sector size to be no larger than 16K. 68.Nm HAMMER 69file systems start at a relative offset of 0 and may only be created 70under out-of-band disk labels 71.Po 72.Xr disklabel64 5 73or 74.Xr gpt 8 75labels 76.Pc , 77or in 78.Xr disklabel32 5 79partitions which do not overlap the label area (have a starting sector 80greater than 16). 81.Pp 82.Nm HAMMER 83file systems are designed for large storage systems, up to 1 Exabyte, and 84will not operate efficiently on small storage systems. 85The minimum recommended file system size is 50GB. 86.Nm HAMMER 87must reserve 500MB to 1GB of its storage for reblocking and UNDO/REDO. 88In addition, 89.Nm HAMMER 90file systems operating normally, with full history 91retention and daily snapshots, do not immediately reclaim space when 92files are deleted. 93A regular system maintenance job runs once a day by 94.Xr periodic 8 95to handle reclamation. 96.Pp 97.Nm HAMMER 98works best when the machine's normal workload would not otherwise fill 99the file system up in the course of 60 days of operation. 100.Pp 101The options are as follows: 102.Bl -tag -width indent 103.It Fl L Ar label 104All 105.Nm HAMMER 106file systems must be named and names should be unique on a 107per-machine basis. 108.It Fl b Ar bootsize 109Specify a fixed area in which a boot related kernel and data can be stored. 110The 111.Ar bootsize 112is specified in bytes. 113By default a boot area of approximately 4MB will be created. 114.It Fl f 115Force operation. 116This is needed for the creation of a 117.Nm HAMMER 118file system less than 10GB size or 119with less than 500MB UNDO/REDO FIFO. 120This should not be used under normal circumstances. 121.It Fl E 122Use TRIM to erase the device's data before creating the file system. 123The underlying device must have the TRIM sysctl enabled. 124Only devices that support TRIM will have such a sysctl option 125.Va ( kern.cam.da.X.trim_enabled ) . 126.It Fl m Ar savesize 127Specify a fixed area which 128.Nm HAMMER 129may use as a memory log. 130This area is currently unused. 131The 132.Ar savesize 133is specified in bytes. 134.It Fl u Ar undosize 135Specify the size of the fixed UNDO/REDO FIFO. 136The 137.Ar undosize 138is specified in bytes. 139By default 0.1% of the root 140volume's size is used, with a reasonable minimum and a reasonable cap. 141The UNDO/REDO FIFO is used to sequence meta-data out to the media for 142instant crash recovery. 143.It Fl V Ar version 144Specify the 145.Nm HAMMER 146file system version to format. 147By default 148.Nm 149formats the file system using the highest production version number 150supported by the 151.Nm HAMMER 152VFS by checking the 153.Va vfs.hammer.supported_version 154sysctl. 155If you need to maintain compatibility with an older version of 156.Nm HAMMER 157you may specify the version with this option. 158.El 159.Pp 160The 161.Ar bootsize , 162.Ar savesize 163and 164.Ar undosize 165must be given with a suffix of 166.Cm K , M , G 167or 168.Cm T 169meaning kilobyte, megabyte, gigabyte and terabyte. 170Lower case can also be used for suffix. 171.Sh EXAMPLES 172.Bd -literal -offset indent 173newfs_hammer -L Home /dev/ad0s1d 174.Ed 175.Pp 176Create a file system named 177.Sq Home 178on 179.Pa /dev/ad0s1d . 180.Sh DIAGNOSTICS 181Exit status is 0 on success and 1 on error. 182.Sh SEE ALSO 183.Xr disklabel32 5 , 184.Xr disklabel64 5 , 185.Xr HAMMER 5 , 186.Xr fdisk 8 , 187.Xr gpt 8 , 188.Xr newfs 8 189.Sh HISTORY 190The 191.Nm 192utility first appeared in 193.Dx 1.11 . 194.Sh AUTHORS 195.An Matthew Dillon Aq Mt dillon@backplane.com 196