Re: [PATCHv5 00/14] git notes

[Johan Herland <johan@herland.net>]

On Tuesday 08 September 2009, Junio C Hamano wrote:
> Johan Herland <johan@herland.net> writes:
> > Furthermore, the following notes tree structures were tested:
> >
> > - "no-notes": Testing without any notes at all. This is only present as
> > a baseline, and to verify that the notes code does not negatively
> > affect performance when not in use.
> 
> Minor nit.
> 
> For this to be a baseline, you would need to have another algorithm
>  before "before", i.e., without any of these notes implementation.
> 
> Comparison with "before" alone is not meaningful.  That is like starting
> with a state with unknown performance regression compared to the stock
> version, and then boast improvements made by various variations.
> 
> You would need to compare overhead of various "algorithms" with the stock
> git in "no-notes" case as well.  It would give us the true performance
> cost of supporting notes.

True. Here is the same table with the baseline ('next') entry on top:


Algorithm / Notes tree   git log -n10 (x100)   git log --all
------------------------------------------------------------
next / no-notes                4.77s              63.84s

before / no-notes              4.78s              63.90s
before / no-fanout            56.85s              65.69s

16tree / no-notes              4.77s              64.18s
16tree / no-fanout            30.35s              65.39s
16tree / 2_38                  5.57s              65.42s
16tree / 2_2_36                5.19s              65.76s

flexible / no-notes            4.78s              63.91s
flexible / no-fanout          30.34s              65.57s
flexible / 2_38                5.57s              65.46s
flexible / 2_2_36              5.18s              65.72s
flexible / ym                  5.13s              65.66s
flexible / ym_2_38             5.08s              65.63s
flexible / ymd                 5.30s              65.45s
flexible / ymd_2_38            5.29s              65.90s
flexible / y_m                 5.11s              65.72s
flexible / y_m_2_38            5.08s              65.67s
flexible / y_m_d               5.06s              65.50s
flexible / y_m_d_2_38          5.07s              65.79s


...Johan

-- 
Johan Herland, <johan@herland.net>
www.herland.net