Re: git svn clone/fetch hits issues with gc --auto

From: Martin Langhoff <martin.langhoff@gmail.com>
Date: Oct 10, 2018, 11:01 UTC
Message-ID: <CACPiFCL0oTjN+-aYgKEDtKC0gYwkv6RLMwakdJV85PJ5XQej6g@mail.gmail.com>
In-Reply-To: <xmqqd0sims6s.fsf@gitster-ct.c.googlers.com>

Looking around, Jonathan Tan's "[PATCH] gc: do not warn about too many loose objects" makes sense to me.

- remove unactionable warning
- as the warning is gone, no gc.log is produced
- subsequent gc runs don't exit due to gc.log

My very humble +1 on that.

As for downsides... if we have truly tons of _recent_ loose objects, it'll ... take disk space? I'm fine with that.

For more aggressive gc options, thoughts:

 - Do we always consider git gc --prune=now "safe" in a "won't delete
stuff the user is likely to want" sense? For example -- are the
references from reflogs enough safety?

 - Even if we don't, for some commands it should be safe to run git gc
--prune=now at the end of the process, for example an import that
generates a new git repo (git svn clone).

cheers,

m On Tue, Oct 9, 2018 at 10:49 PM Junio C Hamano <gitster@pobox.com> wrote:

Show 39 quoted lines

>
> Forwarding to Jonathan, as I think this is an interesting supporting
> vote for the topic that we were stuck on.
>
> Eric Wong <e@80x24.org> writes:
>
> > Martin Langhoff <martin.langhoff@gmail.com> wrote:
> >> Hi folks,
> >>
> >> Long time no see! Importing a 3GB (~25K revs, tons of files) SVN repo
> >> I hit the gc error:
> >>
> >> warning: There are too many unreachable loose objects; run 'git prune'
> >> to remove them.
> >> gc --auto: command returned error: 255
> >
> > GC can be annoying when that happens... For git-svn, perhaps
> > this can be appropriate to at least allow the import to continue:
> >
> > diff --git a/perl/Git/SVN.pm b/perl/Git/SVN.pm
> > index 76b2965905..9b0caa3d47 100644
> > --- a/perl/Git/SVN.pm
> > +++ b/perl/Git/SVN.pm
> > @@ -999,7 +999,7 @@ sub restore_commit_header_env {
> >  }
> >
> >  sub gc {
> > -     command_noisy('gc', '--auto');
> > +     eval { command_noisy('gc', '--auto') };
> >  };
> >
> >  sub do_git_commit {
> >
> >
> > But yeah, somebody else who works on git regularly could
> > probably stop repack from writing thousands of loose
> > objects (and instead write a self-contained pack with
> > those objects, instead).  I haven't followed git closely
> > lately, myself.

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