[Ocfs2-tools-devel] [PATCH 0/3] Add extent list check for discontig block group.

[Joel Becker]

On Thu, Jul 22, 2010 at 10:50:37AM +0800, Tao Ma wrote:
> On 07/22/2010 10:30 AM, Joel Becker wrote:
> >On Thu, Jul 22, 2010 at 09:45:37AM +0800, Tao Ma wrote:
> >>On 07/22/2010 09:18 AM, Joel Becker wrote:
> >>>On Wed, Jul 21, 2010 at 03:24:45PM +0800, Tao Ma wrote:
> >>>>6. if one extent record looks broken while all the others look
> >>>>    sane and complete, remove it(can we ever meet with it?).
> >>>
> >>>	Do you mean that you have 5 records, but the first four add up
> >>>to cpg, so you drop the 5th?
> >>yes, that is what I mean, but it isn't limited to the 5th. So if the 1st
> >>one has a e_leaf_clusters>  total_clusters_in_the_volume, we will
> >>record it as to be fixed, and if the other 4 add up to cpg, we will
> >>remove the 1st. if the other 4 e_leaf_cluster's sum is less than
> >>cpg, we will update 1st e_leaf_clusters accordingly.
> >
> >	I see that in the code, and you coded it correctly, but I'm not
> >sure we want to handle this.  I mean, it's a really weird corruption,
> >and pretending it is OK kind of scares me.  What are the odds the other
> >ones, which look sane, are actually sane?
> So what do you think? Remove the total group? I am fine with it,
> just don't know whether it can really happen.

	Not sure, really.  But if we're going to drop a group for a
slightly-too-larger final extent, we should definitely drop it for
shifted extents.  So drop it.

Joel

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Life's Little Instruction Book #80

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Joel Becker
Consulting Software Developer
Oracle
E-mail: joel.becker at oracle.com
Phone: (650) 506-8127