Re: GUILE 2/3 and string encoding cost

[Han-Wen Nienhuys]

On Wed, Jan 22, 2020 at 11:43 PM David Kastrup <address@hidden> wrote:

> > Actually, the I was comparing the -O2 build with the -O0 build.
> >
> > When recompiling, the Scheme init (reading .scm files) takes 0.31s in 1.8
> > vs. 2.7s in 2.0, a 9x slowdown.
>
> The Guile-2 compiler is doing a lot of optimisations, and LilyPond's
> startup code switches off byte compilation because the dependencies are
> hard to get under control.


where does this happen?

The current codebase at least manages to
> avoid to compile code with as-yet undefined macros, something that
> Guile-1.8 had no problems with but Guile-2.0 refuses.
>

Do you mean that we don't have them anymore, or is there something else
going on?


>
> So the Scheme loading speed is sort-of expected due to Guile relying on
> byte compilation for speed and we switch it off.
>
>
Much to the contrary. Byte-compiling is slow (but running it should be
faster), something you can see from building guile. If it is switched off,
we are getting the "fast" experience.

-- 
Han-Wen Nienhuys - address@hidden - http://www.xs4all.nl/~hanwe
<http://www.xs4all.nl/~hanwen>?