Subject: Re: Data corruption issues possibly involving cgd(4)
To: Daniel Carosone <dan@geek.com.au>
From: Nino Dehne <ndehne@gmail.com>
List: current-users
Date: 01/17/2007 06:38:32
On Wed, Jan 17, 2007 at 04:27:08PM +1100, Daniel Carosone wrote:
> Hmm.  I can only really suspect the filesystem at this point.  How large is it?

Filesystem         1K-blocks      Used     Avail Capacity  Mounted on
/dev/cgd0a         1173977144 1106331136   8947152    99%    /home

or

/dev/cgd0a           1.1T      1.0T      8.5G    99%    /home


> Hrm.  I suspect the filesystem at this point, since you seem to have
> eliminated seeking power and the cgd device.
> 
> Can you tell us more about the fs?  ufs1, ufs2? lfs? :-)
> What size, block and frag size, etc?

# dumpfs /dev/cgd0a
file system: /dev/cgd0a
endian  little-endian
location 65536  (-b 128)
magic   19540119 (UFS2) time    Wed Jan 17 06:29:04 2007
superblock location     65536   id      [ 44a83fa3 10976c51 ]
cylgrp  dynamic inodes  FFSv2   sblock  FFSv2   fslevel 5
nbfree  1055930 ndir    48350   nifree  35933852        nffree  8311
ncg     354     size    147896952       blocks  146747143
bsize   65536   shift   16      mask    0xffff0000
fsize   8192    shift   13      mask    0xffffe000
frag    8       shift   3       fsbtodb 4
bpg     52224   fpg     417792  ipg     103424
minfree 5%      optim   time    maxcontig 1     maxbpg  8192
symlinklen 120  contigsumsize 0
maxfilesize 0x00800400200bffff
nindir  8192    inopb   256
avgfilesize 16384       avgfpdir 64
sblkno  16      cblkno  24      iblkno  32      dblkno  3264
sbsize  8192    cgsize  65536
csaddr  3264    cssize  8192
cgrotor 0       fmod    0       ronly   0       clean   0x02
flags   soft-updates
fsmnt   /home
volname         swuid   0
cs[].cs_(nbfree,ndir,nifree,nffree):
[...]

I hope this includes the info you want. I initialized it back then using
a simple newfs -O 2 under 3.0 I think.


> Another thing you might do is compare sucessive dump(8)s of the
> filesystem.  

I will see what I can do. I never used dump(8) before.


> Oh, you wanted -fn not -pn.

Oops, I even checked the man page. No idea how I ended up with -p. I will
have another test session tomorrow morning when the box is not used as much.
It will have to serve some stuff over the day.


> You're most welcome, and have found at least one concrete problem
> already for your methodical efforts.  I'm very curious now what the
> other problem might be, keep at it..

I'll keep you posted. Thanks again.

Regards,

ND