Date: Fri, 2 Feb 2007 21:05:48 +0100 (CET) From: Oliver Fromme <olli@lurza.secnetix.de> To: freebsd-fs@FreeBSD.ORG Subject: Mysterious block count (reproducible) Message-ID: <200702022005.l12K5mli017338@lurza.secnetix.de>
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Hi
The following is on a standard UFS2 file system under
FreeBSD 6.2, block size 16 KB, fragsize 2 KB. The
filesystems are perfectly ok and fsck-clean. There
haven't been any physical disk errors either.
I've got a file on my home partition that's 214848 bytes.
According to math it should occupy 14 blocks. However:
$ BLOCKSIZE=16K ls -s foo
15 foo
I copied the file to /tmp (which is an mdfs, also UFS2
with default parameters). Same result. I created a
fresh file from /dev/zero of 214848 bytes. The same.
Where does the 15th block come from? Those additional
16 KB must be used for _something_ somewhere ...
fsdb(8) isn't helpful either:
# fsdb -r /dev/md0
fsdb (inum: 2)> ls
[...]
slot 7 ino 5 reclen 20: regular, `foo'
fsdb (inum: 2)> inode 5
current inode: regular file
I=5 MODE=100600 SIZE=214848
BTIME=Feb 2 20:46:02 2007 [0 nsec]
MTIME=Feb 2 20:46:02 2007 [0 nsec]
CTIME=Feb 2 20:46:02 2007 [0 nsec]
ATIME=Feb 2 20:46:58 2007 [0 nsec]
OWNER=root GRP=wheel LINKCNT=1 FLAGS=0 BLKCNT=1e0 GEN=ffffffffe2ca5220
0x1e0 is 224 (== 14 * 16). So fsdb(8) doesn't see the
15th block either. To confirm:
fsdb (inum: 5)> blocks
Blocks for inode 5:
Direct blocks:
2136, 2144, 2152, 2160, 2168, 2176, 2184, 2192, 2248, 2256, 2264, 2272
Indirect blocks:
2280, 2288,
fsdb (inum: 5)>
It lists 12 direct blocks and 2 indirect blocks, that's
still 14 blocks, not 15.
Where did the 15th block go?!? Or is there a bug in
the calculation of ls -s output?
Best regards
Oliver
--
Oliver Fromme, secnetix GmbH & Co. KG, Marktplatz 29, 85567 Grafing b. M.
Handelsregister: Registergericht Muenchen, HRA 74606, USt-Id: DE204219783
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