Re: "failed to read delta base object at..."

On Mon, Aug 25, 2008 at 02:58:05PM -0400, Nicolas Pitre wrote:

On Mon, 25 Aug 2008, J. Bruce Fields wrote:

quoted

Today I got this:

fatal: failed to read delta base object at 3025976 from
/home/bfields/local/linux-2.6/.git/objects/pack/pack-f7261d96cf1161b1b0a1593f673a67d0f2469e9b.pack

This has happened once before recently, I believe with a pack that had
just been created on a recent fetch.  (If I remember correctly, this was
soon after a failed suspend/resume cycle that might have interrupted an
in-progress fetch; could that possible explain the error?)  In that case
I reset origin/master, deleted a tag or two, and fetched, and the
problem seemed to be fixed.

The above error is indicative of a corrupted pack on disk.  To confirm 
it you could use 'git verify-pack' with the given pack file.

That gives:

	error: Packfile .git/objects/pack/pack-f7261d96cf1161b1b0a1593f673a67d0f2469e9b.pack SHA1 mismatch with itself

No surprise, I assume.

With a sufficiently recent git, you only need to copy over another pack 
containing the corrupted object, or the object itself in loose form, 
into your object store to "fix" it.

Yeah, I just did a git repack -a -d in a known good repository and
copied the resulting pack over.  Seems OK.  Thanks.

--b.

As to the source of disk corruptions... that's up to you to find the 
cause amongst many (including a failed suspend).