Re: [linux-lvm] bug in lvs reporting -- version 2.02.07 Debian

["Jun'ichi Nomura" <j-nomura ce jp nec com>]

Hi,

ben scott wrote:
> I have found a couple of times in testing that lvs will sometimes report the 
> same logical volume 2 or more times when output options are used. It seems to 
> happen with volumes that are a large percentage of the total group size. 
> Below I give an example. Notice how "lvs" with no options works fine but with 
> options doesn't.

lvs reports per-lv by default.
However, depending on the specified fields, it reports per-segments
as if '--segments' are given, for the fields are per-segment info.

# lvs
  LV    VG   Attr   LSize  Origin Snap%  Move Log Copy% 
  lvol4 mvg  -wi-a- 21.88G                

# lvs --segments
  LV    VG   Attr   #Str Type   SSize  
  lvol4 mvg  -wi-a-    1 linear  7.45G 
  lvol4 mvg  -wi-a-    1 linear  7.44G 
  lvol4 mvg  -wi-a-    1 linear  6.99G 

In this case, mvg/lvol4 consists of 3 segments.

# dmsetup table mvg-lvol4
0 15613952 linear 8:33 8576
15613952 15605760 linear 8:35 16768
31219712 14655488 linear 8:34 164224

With combination of LVM2 2.02.20 or newer and device-mapper 1.02.16
or newer, you can see which field belongs to which category by
'lvs -o help'.

Thanks,
-- 
Jun'ichi Nomura, NEC Corporation of America