[linux-lvm] Snapshots

[Stuart D. Gathman]

Long ago, Nostradamus foresaw that on Feb 16, Mike Snitzer would write:

>> An elegant part of the LVM system is that the device mapper kernel support is
>> very general, and new data structures can be experimented with entirely in user
>> code - with a script language even.  Metadata for experimental structures does
>> not have to stored with the main metadata.
>
> Please note that the dm-thinp code has metadata in the kernel (on-disk
> format for btrees, etc) much like a filesystem would have.  So there is
> both kernel and userspace (lvm2) metadata for dm-thinp.

Yes, but isn't this loaded into the kernel via userland tools like
device-mapper?  So while a kernel feature would be required for a new
type of kernel metadata, experimental uses of existing formats can
be done in userland.

--
 	      Stuart D. Gathman <stuart at bmsi.com>
     Business Management Systems Inc.  Phone: 703 591-0911 Fax: 703 591-6154
"Confutatis maledictis, flammis acribus addictis" - background song for
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