Re: Post release texi2any performance regression

[Gavin Smith]

On Sun, Oct 29, 2023 at 03:18:14PM +0100, Patrice Dumas wrote:
> In commit
> https://git.savannah.gnu.org/cgit/texinfo.git/commit/?id=7f1b750038f13a58bbd513a6f2f07dda5e87ad3f
> I have modified the code such that with XS the first document built
> out of the parser is a minimal document, without indices/tree, only
> information allowing following XS code to find C data, information
> on errors and some document information (adding novalidate and
> documentlanguage), as there is no perl code needing that information in
> the default XS case.  The document/tree usable in perl is obtained by
> the Texinfo::Structuring::rebuild_document call.

This seems like what was needed - building information on demand.  It
appears to have sped up processing significantly and appears to have
reversed most of if not all of the slowdown.  This is a relief - thanks
for working on this.

I would like to test it more and understand if further optimisations are
possible and understand the changes better but have limited time at the
moment to work on this - hopefully I'll get to it soon.

I don't think that the removal of 'simple_parser' should be significant
for XS; it was a simple synonym for 'parser' in the XS code.  I remember
that using 'simple_parser' was one of the first optimisations we made
to texi2any (from 5.2 onwards) and it made a very significant difference,
but it appears this would only be for non-XS processing.