Bug#383080: lvm2: Excessive running time and disk IO of vgs/lvs/pvs

[Alasdair G Kergon]

On Tue, Aug 15, 2006 at 12:49:05AM +0200, R.J.G. wrote:
> I have run each with 4 '-v' options. Log files are included.
 
They appear truncated - the important bit at the end is missing:-)

But it looks like you have 15 PVs in the same VG and are maintaining
15 copies of the metadata which all have to be maintained in sync.

You should have created most of those PVs with '--metadatacopies 0'
(see the pvcreate man page).  One day this'll get handled automatically,
but the feature is not seen as a priority yet.
To change this now, you'll have to take an up-to-date metadata backup,
use pvcreate with --uuid and --restorefile on some of the PVs
reducing the number of metadatacopies, then vgcfgrestore to put the
metadata back.

Similarly while the code structure is ready to support full metadata
caching, it has not been implemented yet.

Alasdair