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From: Andreas Krey <a.krey@gmx.de>
To: John Szakmeister <john@szakmeister.net>
Cc: "Carlos Martín Nieto" <cmn@elego.de>, neubyr <neubyr@gmail.com>,
	git@vger.kernel.org
Subject: Re: git repository size / compression
Date: Fri, 9 Sep 2011 19:49:37 +0200	[thread overview]
Message-ID: <20110909174937.GA6057@inner.h.iocl.org> (raw)
In-Reply-To: <CAEBDL5U5-1nBGbWtb6+CfBrESoy8+p0Qqw1t1n_5EKFmpq9NhA@mail.gmail.com>

On Fri, 09 Sep 2011 12:05:03 +0000, John Szakmeister wrote:
...
> will at times choose to self-compress the file, instead of doing a
> delta and compressing.  IIRC, there is some heuristics in there for
> determining when to do that, but I forget the exact method.

Don't know about the compression part, but subversion does a delta of the nth
version of a file (not the global revision number n) against the version m, where
m is (n & (n-1)), or the least significant '1' bit flipped to '0'. That way, there
are only O(log(n)) instead of O(n) deltas to apply to get at a specific version.

[Was on the svn users list just then. They described it differently,
 but in essence it's that.]

Andreas

-- 
"Totally trivial. Famous last words."
From: Linus Torvalds <torvalds@*.org>
Date: Fri, 22 Jan 2010 07:29:21 -0800

      reply	other threads:[~2011-09-09 17:50 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-09-09  2:37 git repository size / compression neubyr
2011-09-09  8:23 ` Carlos Martín Nieto
2011-09-09 14:04   ` neubyr
2011-09-09 14:25     ` Sverre Rabbelier
2011-09-09 14:28     ` Carlos Martín Nieto
2011-09-09 15:07       ` neubyr
2011-09-09 14:54     ` Jakub Narebski
2011-09-09 15:09       ` neubyr
2011-09-09 16:05   ` John Szakmeister
2011-09-09 17:49     ` Andreas Krey [this message]

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