Re: unpack a single object

From: tarmigan <tarmigan+lists@gmail.com>
Date: Aug 12, 2009, 05:34 UTC
Message-ID: <905315640908112234y18463675ja35a5b5798793052@mail.gmail.com>
In-Reply-To: <3e8340490908111349j323812dbmf2211e4cf454b8f1@mail.gmail.com>

On Tue, Aug 11, 2009 at 1:49 PM, Bryan Donlan<bdonlan@gmail.com> wrote:

Show 23 quoted lines

> On Tue, Aug 11, 2009 at 4:48 PM, Bryan Donlan<bdonlan@gmail.com> wrote:
>> On Tue, Aug 11, 2009 at 4:15 PM, tarmigan<tarmigan+lists@gmail.com> wrote:
>>> 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.
>>
>
> Err, that should read git hash-object, not git read-file.
>

Thanks, and thanks to Junio who also responded with something similar off-list. I was vaguely familiar with cat-file and hash-object before but didn't realize how they could be used to do what I wanted, so thanks for the lesson.

As Junio suspected, I after the next fsck, I also had problems with the tree associated with that commit and also the commits behind that one. Each fsck takes around 12 minutes, so replacing one commit at a time seemed not very productive. So now I am doing another svn clone from scratch and letting it run for a few hours (it was a straight mirror, so nothing is lost). It seems somewhat wasteful, but I guess better a few hours of cpu time than a few hours of my time.

Thanks, Tarmigan