From mboxrd@z Thu Jan  1 00:00:00 1970
From: Philippe De Muyter <phdm@macq.eu>
Subject: Re: identical hashes on two branches, but holes in git log
Date: Thu, 21 May 2015 09:05:23 +0200
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References: <20150519132958.GA21130@frolo.macqel> <20150519233925.GA22748@peff.net> <20150520131359.GA7043@frolo.macqel> <20150520132534.GI10518@serenity.lan> <20150520141238.GA13990@frolo.macqel> <20150520161815.GA12521@peff.net>
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Cc: John Keeping <john@keeping.me.uk>, git@vger.kernel.org
To: Jeff King <peff@peff.net>
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On Wed, May 20, 2015 at 12:18:15PM -0400, Jeff King wrote:
> On Wed, May 20, 2015 at 04:12:38PM +0200, Philippe De Muyter wrote:
> 
> > After reading the man page of 'git log', should --topo-order not be the
> > default log order ?
> 
> The problem with --topo-order is that it has to traverse all of the
> commits before starting output. So:
> 
>   $ time git log | head -1
>   commit 64fb1d0e975e92e012802d371e417266d6531676
> 
>   real    0m0.038s
>   user    0m0.032s
>   sys     0m0.008s
> 
>   $ time git log --topo-order | head -1
>   commit 64fb1d0e975e92e012802d371e417266d6531676
> 
>   real    0m4.247s
>   user    0m4.140s
>   sys     0m0.108s
> 
> -Peff

So we trade correctness for speed :(

Is there a way to set topo-order as the default log order via git config ?

Is topo-order already implemented as starting with the default order followed
by an ancestor check or does it switch immediately to topological sort ?

Philippe