Re: [PATCH] Inline highlighting performance improvements

[Kai Willadsen <kai willadsen gmail com>]

On 30 April 2012 20:13, Piotr Piastucki <leech miranda gmail com> wrote:
> Hi,
>
> The attached patch introduces a new matcher class that provides additional
> optimizations more suitable for character-based matching. Some code
> refactoring is also included to make easier to extend preprocessing phase in
> MyersSequenceMatcher class. The optimization assumes that the minimum number
> of matching characters is 3. I ran some simple tests and
> InlineMyersSequenceMatcher seems to be up to 8 times faster when the files
> are almost completely different.

I just wanted to note that this *is* something I'm looking at. The
changes look good, but I'm trying to see whether I can unravel the
InlineMyersSequenceMatcher preprocessing to be somewhat more
understandable.

Also, the attached patch has a bug: InlineMyersSequenceMatcher is
derived from difflib.SequenceMatcher instead of MyersSequenceMatcher,
which is what was obviously intended.

Also, I do see significant performance gains from using the inline
optimisations, so if it doesn't affect the quality of matches too
much, I definitely want to get it in.

cheers,
Kai