[linux-lvm] Why does every lvm command insist on touching every pv?

[Takahiro Yasui]

On 06/16/10 05:30, Zdenek Kabelac wrote:
> Dne 16.6.2010 02:34, Phillip Susi napsal(a):
>> On 06/15/2010 04:41 PM, Takahiro Yasui wrote:
...
>> What if I don't want ANY devices to be scanned every time an lvm command
>> is run?  Shouldn't they be scanned once when udev first detects they
>> have been attached, and no more?  I thought removing /dev from the scan=
>> line would do that, but it didn't.
>>
> 
> I'd have say - this is work-in-progress for now - yes, udev should handle all 
> this for lvm - but we are not yet there...

Hi Zdenek,

Sorry I passed over your post.

May I ask you how you are going to handle this issue by udev? The problem
is *not* a scan of devices to update dev-cache but a scan of devices to
update lvm metadata cache in memory by lvm command. Currently lvm does
not have a kind of metadata cache on a device (e.g. /etc/lvm) and lvm
command has to get metadata information stored on each PV whenever it is
executed.

It is helpful if udev can handle this issue, but I'm wondering how it can
do it.

Thanks,
Taka