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diff --git a/share/man/man5/tmpfs.5 b/share/man/man5/tmpfs.5 deleted file mode 100644 index f3d6a2f6c2b5..000000000000 --- a/share/man/man5/tmpfs.5 +++ /dev/null @@ -1,229 +0,0 @@ -.\"- -.\" Copyright (c) 2007 Xin LI -.\" Copyright (c) 2017 The FreeBSD Foundation, Inc. -.\" -.\" Part of this documentation was written by -.\" Konstantin Belousov <kib@FreeBSD.org> under sponsorship -.\" from the FreeBSD Foundation. -.\" -.\" Redistribution and use in source and binary forms, with or without -.\" modification, are permitted provided that the following conditions -.\" are met: -.\" 1. Redistributions of source code must retain the above copyright -.\" notice, this list of conditions and the following disclaimer. -.\" 2. Redistributions in binary form must reproduce the above copyright -.\" notice, this list of conditions and the following disclaimer in the -.\" documentation and/or other materials provided with the distribution. -.\" -.\" THIS DOCUMENTATION IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR -.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES -.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. -.\" IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, -.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT -.\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, -.\" DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY -.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT -.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF -.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. -.\" -.\"- -.\" Copyright (c) 2005, 2006 The NetBSD Foundation, Inc. -.\" All rights reserved. -.\" -.\" Redistribution and use in source and binary forms, with or without -.\" modification, are permitted provided that the following conditions -.\" are met: -.\" 1. Redistributions of source code must retain the above copyright -.\" notice, this list of conditions and the following disclaimer. -.\" 2. Redistributions in binary form must reproduce the above copyright -.\" notice, this list of conditions and the following disclaimer in the -.\" documentation and/or other materials provided with the distribution. -.\" -.\" THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS -.\" ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED -.\" TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR -.\" PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS -.\" BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR -.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF -.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS -.\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN -.\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) -.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE -.\" POSSIBILITY OF SUCH DAMAGE. -.\" -.Dd September 18, 2023 -.Dt TMPFS 5 -.Os -.Sh NAME -.Nm tmpfs -.Nd "in-memory file system" -.Sh SYNOPSIS -To compile this driver into the kernel, -place the following line in your -kernel configuration file: -.Bd -ragged -offset indent -.Cd "options TMPFS" -.Ed -.Pp -Alternatively, to load the driver as a -module at boot time, place the following line in -.Xr loader.conf 5 : -.Bd -literal -offset indent -tmpfs_load="YES" -.Ed -.Sh DESCRIPTION -The -.Nm -driver implements an in-memory, or -.Nm -file system. -The filesystem stores both file metadata and data in main memory. -This allows very fast and low latency accesses to the data. -The data is volatile. -An umount or system reboot invalidates it. -These properties make the filesystem's mounts suitable for fast -scratch storage, like -.Pa /tmp . -.Pp -If the system becomes low on memory and swap is configured -.Po see -.Xr swapon 8 Pc , -the system can transfer file data to swap space, freeing memory -for other needs. -Metadata, including the directory content, is never swapped out by the -current implementation. -Keep this in mind when planning the mount limits, especially when expecting -to place many small files on a tmpfs mount. -.Pp -When -.Xr mmap 2 -is used on a file from a tmpfs mount, the swap VM object managing the -file pages is used to implement mapping and avoid double-copying of -the file data. -This quirk causes process inspection tools, like -.Xr procstat 1 , -to report anonymous memory mappings instead of file mappings. -.Sh OPTIONS -The following options are available when -mounting -.Nm -file systems: -.Bl -tag -width "maxfilesize" -.It Cm easize -Set the maximum memory size used by extended attributes in bytes. -The default is 16 megabytes. -.It Cm export -Accept the -.Cm export -option for compatibility with -.Xr nfsv4 4 . -This option does nothing. -.It Cm gid -Set the group ID of the root inode of the file system. -The default is the mount point's GID. -.It Cm inodes -Set the maximum number of nodes available to the file system. -If not specified, the file system chooses a reasonable maximum based on -the file system size, which can be limited with the -.Cm size -option. -.It Cm maxfilesize -Set the maximum file size in bytes. -The default is the maximum possible value. -.It Cm mode -Set the mode (in octal notation) of the root inode of the file system. -The default is the mount point's mode. -.It Cm nomtime -Disable the tracking of mtime updates caused by writes to the -shared mapped areas backed by -.Nm -files. -This option removes periodic scans, -which downgrade read-write-mapped pages to read-only to note the writes. -.It Cm nonc -Do not use namecache to resolve names to files for the created mount. -This saves memory, but currently might impair scalability for highly -used mounts on large machines. -.It Cm nosymfollow -Do not follow -.Xr symlink 7 Ap s -on the mounted file system. -.It Cm pgread -Enable pgcache read for the mount. -.It Cm size -Set the total file system size in bytes, unless suffixed -with one of k, m, g, t, or p, which denote byte, kilobyte, -megabyte, gigabyte, terabyte and petabyte respectively. -If zero (the default) or a value larger than SIZE_MAX - PAGE_SIZE -is given, the available amount of memory (including -main memory and swap space) will be used. -.It Cm uid -Set the user ID of the root inode of the file system. -The default is the mount point's UID. -.It Cm union -Refer to -.Xr mount 8 . -.El -.Sh SYSCTL VARIABLES -The following -.Xr sysctl 8 -variables are available: -.Bl -tag -width indent -.It Va vfs.tmpfs.memory_percent -The percentage of memory plus swap space available at kernel file system -initialization that can be used by a file system with a size of 0. -When this amount of space in use is reached, new files cannot be created -and files cannot be extended. -The default is 95%. -Changing this value also changes -.Va vfs.tmpfs.memory_reserved . -.It Va vfs.tmpfs.memory_reserved -The currently-reserved amount of memory plus swap space -based on the memory percentage. -The minimum is compiled into the system, and defaults to 4 MB. -.El -.Sh EXAMPLES -Mount a -.Nm -memory file system: -.Pp -.Dl "mount -t tmpfs tmpfs /tmp" -.Pp -Configure a -.Nm -mount via -.Xr fstab 5 : -.Bd -literal -offset indent -tmpfs /tmp tmpfs rw 0 0 -.Ed -.Sh SEE ALSO -.Xr procstat 1 , -.Xr mmap 2 , -.Xr nmount 2 , -.Xr unmount 2 , -.Xr fstab 5 , -.Xr mdmfs 8 , -.Xr mount 8 , -.Xr swapinfo 8 , -.Xr swapon 8 -.Sh HISTORY -The -.Nm -driver first appeared in -.Fx 7.0 . -.Sh AUTHORS -.An -nosplit -The -.Nm -kernel implementation was written by -.An Julio M. Merino Vidal Aq Mt jmmv@NetBSD.org -as a Google Summer of Code project. -.Pp -.An Rohit Jalan -and others ported it from -.Nx -to -.Fx . -.Pp -This manual page was written by -.An Xin LI Aq Mt delphij@FreeBSD.org . |