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

From: J. Bruce Fields <bfields@fieldses.org>
Date: Aug 25, 2008, 21:18 UTC
Message-ID: <20080825211830.GH2213@fieldses.org>
In-Reply-To: <alpine.LFD.1.10.0808251445090.1624@xanadu.home>

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

Show 16 quoted lines

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