[linux-lvm] LVM 0.8final for 2.2.15/2.2.16?
Michael Marxmeier
mike at msede.com
Thu Jun 8 02:22:14 UTC 2000
>
> On Wed, 7 Jun 2000, Jan Niehusmann wrote:
>
> > The snapshot logic simply doesn't know what a filesystem is. It just
> > clones the block device.
>
> this i knew.. :)
>
> > So the fs may be in en inconsistent state, if you do the snapshot
> > while some write operation is in progress on the cloned
> > filesystem.
>
> ok. so the solution is what? a call in the vfs to complete pending
> writes, and hold off on modifying any blocks?
IMHO when creating a snapshot LVM could simply sync all outstanding
buffers for the block device vialog block_fsync() (not sure if this
is already done -- Heinz care to comment?).
This should also take care of pending fs meta information thus
we should get a consistent state.
The question is how atomic this is? Since fsync_dev() currently
does a lock_kernel() is might even be sufficient.
Any reason why this is not suffiecient?
Michael
--
Michael Marxmeier Marxmeier Software AG
E-Mail: mike at msede.com Besenbruchstrasse 9
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