From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Shawn O. Pearce" <spearce@spearce.org>
Subject: Re: People unaware of the importance of "git gc"?
Date: Fri, 7 Sep 2007 00:48:41 -0400
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Cc: Johannes Schindelin <Johannes.Schindelin@gmx.de>,
	Nicolas Pitre <nico@cam.org>, Nix <nix@esperi.org.uk>,
	Steven Grimm <koreth@midwinter.com>,
	Linus Torvalds <torvalds@linux-foundation.org>,
	Git Mailing List <git@vger.kernel.org>
To: Junio C Hamano <gitster@pobox.com>
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Junio C Hamano <gitster@pobox.com> wrote:
> Johannes Schindelin <Johannes.Schindelin@gmx.de> writes:
> 
> > On Wed, 5 Sep 2007, Junio C Hamano wrote:
> >>  static int aggressive_window = -1;
> >> +static int gc_auto_threshold = 6700;
> >
> > Please don't do that.
> >
> > When you share objects with another git directory, git-gc --auto can get 
> > rid of the objects when some objects go away in the referenced repository.  
> 
> I thought the whole point of "gc --auto" was to have something
> that does not lose/prune any objects, even the ones that do not
> seem to be referenced from anywhere.  That is why invocations of
> "git gc --auto" do not say --prune as you saw the second patch,
> and the repack command "gc --auto" runs is "repack -d -l"
> instead of "repack -a -d -l", which means that it does run
> git-prune-packed after repacking but not git-prune.
> 
> Maybe I am missing something...

No, you aren't Junio.  `gc --auto` as you defined it is safe.
It won't delete objects from the database.  So it won't impact shared
repositories, or readers that are actively running in parallel with
the gc.  Both of which are important.

-- 
Shawn.