Re: [PATCH 11/11] tree-diff: reuse base str(buf) memory on sub-tree recursion

From: Kirill Smelkov <kirr@mns.spb.ru>
Date: Feb 13, 2014, 13:25 UTC
Message-ID: <20140213132524.GA15450@tugrik.mns.mnsspb.ru>
In-Reply-To: <645beb40c13912e87f6fe67d46af2b5e81dcaaca.1391794688.git.kirr@mns.spb.ru>

On Fri, Feb 07, 2014 at 09:48:52PM +0400, Kirill Smelkov wrote:

Show 12 quoted lines

> instead of allocating it all the time for every subtree in
> __diff_tree_sha1, let's allocate it once in diff_tree_sha1, and then all
> callee just use it in stacking style, without memory allocations.
> 
> This should be faster, and for me this change gives the following
> slight speedups for `git log --raw --no-abbrev --no-renames`
> 
>                 navy.git    linux.git v3.10..v3.11
> 
>     before      0.547s      1.791s
>     after       0.541s      1.777s
>     speedup     1.1%        0.8%

The timings above was done with

    `git log --raw --no-abbrev --no-renames --format='%H'`
                                            ^^^^^^^^^^^^^

Please change them to correct timings:

                navy.git    linux.git v3.10..v3.11

    before      0.618s      1.903s
    after       0.611s      1.889s
    speedup     1.1%        0.7%

Thanks, Kirill