Lilypond speed (was Re: How to make GNU Guile more successful)

[Andy Wingo]

On Sun 05 Mar 2017 15:01, Thomas Morley <address@hidden> writes:

> Here some timing values
>
> (1)
> lilypond-2.19.52 using guile 1.8.7
> (I would have prefered to build lilypond with a guile-1.8.8 build from
> the guile-repository. Though my try to build it from the
> branch_release-1-8 failed. Instead attempting to fix it, I then used a
> released lilypond-version)
>
> real    8m16.191s
> user    6m39.864s
> sys    0m10.860s
>
> (2)
> guile-2.0.14 build from guile-git-repository, branch remotes/origin/stable-2.0
> lilypond-2.19.56, build from local branch dev/guile-v2.2-work
>
> real    34m11.762s
> user    45m11.316s
> sys    0m5.604s
>
> (3)
> guile-2.1.7 build from guile-git-repository, branch master
> (I've got this warning:
> configure: WARNING: *** GNU Readline is too old on your system.
> configure: WARNING: *** You need readline version 2.1 or later.
> No idea whether this may have an impact on lilyponds compiling-time
> I'll have to test.)
> lilypond-2.19.56, build from local branch dev/guile-v2.2-work
>
> real    67m29.132s
> user    93m14.812s
> sys    0m7.332s

Oh, that's interesting.  IME the only thing that is slower on 2.2
compared to 2.0 is the compiler; everything else is significantly
faster.  Could it be that Lilypond is spending time compiling things
somehow?  Perhaps via scm_load without disabling autocompilation or
something?  Guessing at this point tho.

But that's getting ahead of myself -- do you have a document that
exhibits a similar performance series (1.8 < 2.0 < 2.2) but which
doesn't take so long to run?  That can make perf investigation a bit
more tractable :)

Andy