Re: unpack a single object
On Tue, Aug 11, 2009 at 4:15 PM, tarmigan<tarmigan+lists@gmail.com> wrote:
Show 44 quoted lines
> Hi,
>
> At work we use SVN. To deal with this I mirror the svn repo with
> git-svn and have a cron job that runs git svn rebase every hour, and
> then I rebase from that git repo.
>
> Unfortunately, on the computer that runs the cron job, /home ran out
> of space. After making more space and deleting the
> svn/trunk/.rev_map, my 'git svn rebase' dies with a
>> git svn rebase
> Rebuilding .git/svn/trunk/.rev_map.4279b43a-dd95-8640-b069-b0d2992e4ff2 ...
> error: Could not read 3d4c2b0225e7605a7e2a38ffc44dcb888589f4ce
> fatal: Failed to traverse parents of commit
> 31c4379db99f05d0942e7c204b38f7b587fb4d3b
> rev-list --pretty=raw --no-color --reverse refs/remotes/trunk --:
> command returned error: 128
>
> So I look for corruption with
>> git fsck --full --strict
> broken link from commit 31c4379db99f05d0942e7c204b38f7b587fb4d3b
> to commit 3d4c2b0225e7605a7e2a38ffc44dcb888589f4ce
> dangling blob a6027cd01178f19243342c0f6ccaef8fb798dcf4
> <snipped more dangling blobs>
> dangling blob 4348d7ebd189208716b44bcf4198c1f29d18e6c3
> missing commit 3d4c2b0225e7605a7e2a38ffc44dcb888589f4ce ******
> dangling blob 22757bac2e3433cccd9d7e32fa79d90031e14353
> dangling blob 1276575eca02976ff677b61a6873562db7db31d7
> dangling blob f98343007ac9d2f33a81fe25f4d446b045c3167a
> dangling blob d29043a6e2b87cd0be1f3fb39f0c88283b79409b
> dangling blob f7d08b39830709c044279d17d3d85cbe813998bb
> dangling blob 64f14b305164f65c788dc9970deb7dfc79ac7446
>
> Thankfully, I have copies of the repo and this object (3d4c2b) in
> other location and that passes git-fsck. Strangely, it is a commit
> object from about 18 month ago and should have been in a pack for a
> long time, so maybe running out of disk space was not the cause.
>
> I would rather not copy the whole good repo back to the one that ran
> out of space because it's multiple gigs. My plan is to just explode
> the bad pack on of the corrupted repo, explode good pack and then,
> copy the corrupted object back. So my question is how do I tell which
> pack contains that object? (I would rather not explode all the packs
> because of the repo size.) Is there a way to extract a single object
> from a pack without exploding the whole pack?
You should be able to just extract the single object in question:
goodrepo$ git cat-file commit 3d4c2b0225e7605a7e2a38ffc44dcb888589f4ce
> ~/commit.dat
goodrepo$ cd ~/badrepo
badrepo$ git read-file -t commit ~/commit.dat
(should output 3d4c2b0225e7605a7e2a38ffc44dcb888589f4ce)
At this point your repo should be repaired.