running time for a full fsck. It also reduces the random access time
for large files and speeds the traversal time for directory tree walks.
The key idea is to reserve a small area in each cylinder group
immediately following the inode blocks for the use of metadata,
specifically indirect blocks and directory contents. The new policy
is to preferentially place metadata in the metadata area and
everything else in the blocks that follow the metadata area.
The size of this area can be set when creating a filesystem using
newfs(8) or changed in an existing filesystem using tunefs(8).
Both utilities use the `-k held-for-metadata-blocks' option to
specify the amount of space to be held for metadata blocks in each
cylinder group. By default, newfs(8) sets this area to half of
minfree (typically 4% of the data area).
This work was inspired by a paper presented at Usenix's FAST '13:
www.usenix.org/conference/fast13/ffsck-fast-file-system-checker
Details of this implementation appears in the April 2013 of ;login:
www.usenix.org/publications/login/april-2013-volume-38-number-2.
A copy of the April 2013 ;login: paper can also be downloaded
from: www.mckusick.com/publications/faster_fsck.pdf.
Reviewed by: kib
Tested by: Peter Holm
MFC after: 4 weeks
operate on one type of filesystem, mention this.
While here, capitalise the use of "UFS" in growfs.8 to match other uses of
the term in other man pages.
MFC after: 1 week
brings in support for an optional intent log which eliminates the need
for background fsck on unclean shutdown.
Sponsored by: iXsystems, Yahoo!, and Juniper.
With help from: McKusick and Peter Holm
command, permitting it to set FS_ACLS and FS_MULTILABEL administrative
flags on UFS file systems.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
filesystem expands the inode to 256 bytes to make space for 64-bit
block pointers. It also adds a file-creation time field, an ability
to use jumbo blocks per inode to allow extent like pointer density,
and space for extended attributes (up to twice the filesystem block
size worth of attributes, e.g., on a 16K filesystem, there is space
for 32K of attributes). UFS2 fully supports and runs existing UFS1
filesystems. New filesystems built using newfs can be built in either
UFS1 or UFS2 format using the -O option. In this commit UFS1 is
the default format, so if you want to build UFS2 format filesystems,
you must specify -O 2. This default will be changed to UFS2 when
UFS2 proves itself to be stable. In this commit the boot code for
reading UFS2 filesystems is not compiled (see /sys/boot/common/ufsread.c)
as there is insufficient space in the boot block. Once the size of the
boot block is increased, this code can be defined.
Things to note: the definition of SBSIZE has changed to SBLOCKSIZE.
The header file <ufs/ufs/dinode.h> must be included before
<ufs/ffs/fs.h> so as to get the definitions of ufs2_daddr_t and
ufs_lbn_t.
Still TODO:
Verify that the first level bootstraps work for all the architectures.
Convert the utility ffsinfo to understand UFS2 and test growfs.
Add support for the extended attribute storage. Update soft updates
to ensure integrity of extended attribute storage. Switch the
current extended attribute interfaces to use the extended attribute
storage. Add the extent like functionality (framework is there,
but is currently never used).
Sponsored by: DARPA & NAI Labs.
Reviewed by: Poul-Henning Kamp <phk@freebsd.org>
We need to parse the arguments first, then open the device (if
specified) and then apply the changes. This change will disallow the
(undocumented) use of multiple instances of the same argument on the
same command line for the sack of a better error message.
Other changes are:
1) the softupdates (-n) now issue a warning about remaining unchanged
2) the usage and man page is changed to specify "space | time" instead of
"optimization preference".
PR: bin/23335
Submitted by:Mark Peek <mark@whistle.com>
parameters are. You can use dumpfs, but that's not obvious which settings
are tuneable, and is far from clear to the non-guru (it's like using a
hexdump of a tar archive to get a table-of-contents).
There is also an undocumented option in the man page that can be dangerous.
Suppose your disk driver decides to scramble all writes while you tell
tunefs to update all backup superblocks.
This suggested change adds a '-p' (print) switch to bring it in
line with some SVR4 systems.
(Slightly changed by me, mostly for optics. - joerg)
Submitted by: peter@haywire.dialix.com
