path: root/sbin/dumpfs
diff options
authorKirk McKusick <mckusick@FreeBSD.org>2013-03-22 21:45:28 +0000
committerKirk McKusick <mckusick@FreeBSD.org>2013-03-22 21:45:28 +0000
commitbaa12a84a7aefc1a1932a7568eaf7d2d55b5d21c (patch)
tree4dd79ec73ca7a215a3694baba70bbfe162604d09 /sbin/dumpfs
parent209dddb90e6ee833590836dc48a58957fd6f3026 (diff)
The purpose of this change to the FFS layout policy is to reduce the
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
Notes: svn path=/head/; revision=248623
Diffstat (limited to 'sbin/dumpfs')
1 files changed, 2 insertions, 2 deletions
diff --git a/sbin/dumpfs/dumpfs.c b/sbin/dumpfs/dumpfs.c
index a41ca4dda719..6669d532d62e 100644
--- a/sbin/dumpfs/dumpfs.c
+++ b/sbin/dumpfs/dumpfs.c
@@ -241,8 +241,8 @@ dumpfs(const char *name)
afs.fs_sblkno, afs.fs_cblkno, afs.fs_iblkno, afs.fs_dblkno);
afs.fs_cgrotor, afs.fs_fmod, afs.fs_ronly, afs.fs_clean);
- printf("avgfpdir %d\tavgfilesize %d\n",
- afs.fs_avgfpdir, afs.fs_avgfilesize);
+ printf("metaspace %jd\tavgfpdir %d\tavgfilesize %d\n",
+ afs.fs_metaspace, afs.fs_avgfpdir, afs.fs_avgfilesize);
if (afs.fs_old_flags & FS_FLAGS_UPDATED)
fsflags = afs.fs_flags;