Re: 78% speed up in CC Mode scrolling.

[Alan Mackenzie]

Hello, Martin.

On Thu, Jul 07, 2016 at 06:17:32PM +0200, martin rudalics wrote:
>  > Scrolling through emacs-25's xdisp.c, I get the following timings:
>  >    emacs-25 branch: 45.529s
>  >    master branch:   25.529s

>  > This is a speedup of around 78%.

> Thank you.  Using the attached test2.el on frame.c, I get the following
> results for emacs -Q (‘foofoo’ scrolls up profiling ‘foo-1’, ‘foobar’
> scrolls down profiling ‘bar-1’).

> emacs-25:

>                 Call Count  Elapsed Time  Average Time
> foo-1          169         109.15699999  0.6458994082
> bar-1          169         113.032       0.6688284023

> master:

> foo-1          169          45.28100000  0.2679349112
> bar-1          169          53.406       0.3160118343

> These look even better than yours (I have no idea which formula you used
> to derive a speedup of "78%" though).

Simply 45.529 / 25.529 = 1.78.

In your timings I see a speed increase of 141% and 112% respectively.
It'd be nice if your results were more typical than mine.

What is pure coincidence (I hope) is how similar the digits in my two
timings were.

> martin

-- 
Alan Mackenzie (Nuremberg, Germany).