[linux-lvm] What todo if metadata grows faster than pool data

[linux-lvm] What todo if metadata grows faster than pool data

[Oliver Rath]

Hi list,

in my thinpool-volume the used data is now 50% but the used metadata
size is 82%. What happens, if the metadata a running full, bevor data is
full? Do I have to modify metadata size explicitly or does lvm this
automaticly? How can I do this?

At the moment 78 volumes or snaps had been created from this
winthinpool, mostly with size about 100GB.

Tfh,
OIiver 

--- Logical volume ---
  LV Name                winthinpool
  VG Name                dmivg
  LV UUID                gDGkhM-jGQq-hSuZ-g4CZ-JtcQ-JcdX-DqD7bi
  LV Write Access        read/write
  LV Creation host, time dmicn20, 2014-10-07 23:54:45 +0200
  LV Pool metadata       winthinpool_tmeta
  LV Pool data           winthinpool_tdata
  LV Status              available
  # open                 73
  LV Size                930,00 GiB
  Allocated pool data    50,73%
  Allocated metadata     82,61%
  Current LE             238080
  Segments               1
  Allocation             inherit
  Read ahead sectors     auto
  - currently set to     256
  Block device           252:18

Re: [linux-lvm] What todo if metadata grows faster than pool data

[Mike Snitzer]

On Fri, Oct 24 2014 at 10:08am -0400,
Oliver Rath <rath@mglug.de> wrote:

> Hi list,
> 
> in my thinpool-volume the used data is now 50% but the used metadata
> size is 82%. What happens, if the metadata a running full, bevor data is
> full? Do I have to modify metadata size explicitly or does lvm this
> automaticly? How can I do this?

You'll want to grow the metadata volume.  Newer versions of the
dm-thinp kernel code and lvm2 userspace code make this possible.

See the "Manually manage free metadata space of a thin pool LV" section
of the lvmthin.7 manpage in a recent lvm2 release.

[linux-lvm] SOLVED [was Re: What todo if metadata grows faster than pool data]

[Oliver Rath]

Hi Mike!

Im using lvim 2.02.110 with kernel 3.16.


Am 24.10.2014 um 16:18 schrieb Mike Snitzer:
> On Fri, Oct 24 2014 at 10:08am -0400,
> You'll want to grow the metadata volume.  Newer versions of the
> dm-thinp kernel code and lvm2 userspace code make this possible.
>
> See the "Manually manage free metadata space of a thin pool LV" section
> of the lvmthin.7 manpage in a recent lvm2 release.

Hour hint to the tmvthin-manpage was right:

lvextend -L+96M dmivg/winthinpool_tmeta

worked!

Now Metadata is safe:

  --- Logical volume ---
  LV Name                winthinpool
  VG Name                dmivg
  LV UUID                gDGkhM-jGQq-hSuZ-g4CZ-JtcQ-JcdX-DqD7bi
  LV Write Access        read/write
  LV Creation host, time dmicn20, 2014-10-07 23:54:45 +0200
  LV Pool metadata       winthinpool_tmeta
  LV Pool data           winthinpool_tdata
  LV Status              available
  # open                 73
  LV Size                930,00 GiB
  Allocated pool data    50,85%
  Allocated metadata     45,91%
  Current LE             238080
  Segments               1
  Allocation             inherit
  Read ahead sectors     auto
  - currently set to     256
  Block device           252:18


Tfh!

Oliver