On Wed, Feb 5, 2020 at 5:23 PM Ludovic Courtès <ludo@gnu.org> wrote:

> Weird.  It would be interesting to see where the slowdown comes from.
> Overall, my recollection of the 1.8 to 2.0 transition (where we
> introduced libgc) is that GC was a bit faster, definitely not slower.
>
> That said, does LilyPond happen to use lots of bignums and/or lots of
> finalizers?  Finalizers, including those on bignums, end up being very
> GC-intensive, as discussed in my recent message.  Perhaps that’s what’s
> happening here, for instance if you create lots of SMOBs with a free
> function.
>

No, I think it's because in some phases of the program, there is a lot of
heap growth, with little garbage generation. This causes frequent
(expensive) GCs that don't reclaim anything.


-- 
Han-Wen Nienhuys - hanwenn@gmail.com - http://www.xs4all.nl/~hanwen