Re: [PATCH] add the ability to create and retrieve delta objects

From: Geert Bosch <bosch@adacore.com>
Date: May 4, 2005, 21:47 UTC
Message-ID: <DE5D04E8-B182-45B1-AB9A-6AA178005FFD@adacore.com>
In-Reply-To: <200505041156.19499.mason@suse.com>

 From your tests it would seem that the zdelta version is the only one
to provide a uniform improvement over plain git. As it also seems the
simplest approach, I wonder why the consensus is that using xdiff
would be better?

   -Geert

On May 4, 2005, at 11:56, Chris Mason wrote:

Show 20 quoted lines

> I did two additional runs, first where I fixed the delta chain  
> length at 1 as
> in the zdelta patch.   In this mode, if it tried to diff against a  
> delta it
> would find the delta's parent and diff against that instead.  Even  
> though
> zdelta had the same speeds for applying patches as xdiff(1), zdelta  
> used
> significantly more cpu (53m vs 40m).
>
> The next run was with the patch I've attached below, it allows  
> chains up to 16
> deltas in length.
>                              git         zdelta       xdiff  
> (1)      xdiff(16)
> apply                  150m       117m       117m         104m
> checkout             4m30s      3m41      4m43s        7m11s
> checkout (hot)     56s           12s         14s             16s
> space usage        2.5G         1G           1.2G           800m
>