Re: git-reflog 70 minutes at 100% cpu and counting

From: Steven Noonan <steven@uplinklabs.net>
Date: Dec 18, 2009, 04:26 UTC
Message-ID: <f488382f0912172026ye9950c9sd4f505d8db1e47d1@mail.gmail.com>
In-Reply-To: <alpine.LFD.2.00.0912172255500.23173@xanadu.home>

On Thu, Dec 17, 2009 at 7:57 PM, Nicolas Pitre <nico@fluxnic.net> wrote:

Show 45 quoted lines

> On Thu, 17 Dec 2009, Steven Noonan wrote:
>
>> On Thu, Dec 17, 2009 at 7:33 PM, Nicolas Pitre <nico@fluxnic.net> wrote:
>> > On Thu, 17 Dec 2009, Eric Paris wrote:
>> >
>> >> This alone almost certainly tells me how I broke it.
>> >>
>> >> For quite some time (a period of months) linux-next was broken and I had
>> >> to carry a patch to ACPI to make it boot.  I dropped that patch at the
>> >> head of my stgit trees in all of my repositories.  So I wouldn't be at
>> >> all surprised to learn that eventually kernel-2 found that object in
>> >> kernel-1.  Sometime when I dropped that patch from kernel-1 (because it
>> >> finally got fixed upstream) I can see how it broke.
>> >>
>> >> But now that patch shouldn't be needed by any tree since I have long
>> >> since dropped it from the stgit stack.  So if we cleaned up all of the
>> >> useless objects in this tree I bet this object wouldn't be needed.  Not
>> >> exactly a situation that I'd expect git to be able to dig out of itself
>> >> thought.
>> >
>> > I let the script I provided previously ran for a while.  And the commit
>> > I found to contain the missing object belongs to
>> > refs/patches/fsnotify/fsnotify-group-priorities.log.  So I simply
>> > deleted that branch entirely and now the repack can proceed.  And with a
>> > 'git gc --aggressive' the 1.2GB repository shrank to a mere 5.2 MB.  :-)
>> > Of course I didn't bring back all the reflogs though.  But I would
>> > have expected a repository reduction of the same magnitude even with
>> > them.
>> >
>>
>> Are we talking about the same Linux kernel repository as before?
>
> As before in this thread.
>
>> Because if so, that reduction in size doesn't make any sense to me.
>
> Sure it does.
>
>> The smallest size I've seen for the Linux kernel repository (in the
>> past year) is 250MB.
>
> Depends if you have an alternate repository from which you may borrow
> objects from, which was the case here.  In that context, 1.2 GB of disk
> space was completely insane.
>

Ahh. That makes sense. I should really read up on alternates then.

- Steven