Lilypond slow to start up on the Mac

[Arle Lommel]

I’ve noticed on the Mac for some time that the first time I invoke Lilypond 
from an external application after a reboot, it can take quite a while for it 
to respond. Normally this is something like a 40–60 second delay, after which 
Lilypond behaves normally. But a few days ago, after I updated to OS X 10.13.4, 
it seemed that Lilypond was totally unresponsive over much longer periods. 
After waiting about ten minutes, I finally walked away for dinner, and when I 
came back, it was working normally. This happened with the latest development 
build, but I’ve also had delays with the stable build (although never as long 
as this was).

I was invoking Lilypond through Frescobaldi, but I’ve had the same (shorter) 
initial delays on JEdit, and on multiple machines in the past.

During this longer wait, I could launch Lilypond.app and initiate a typesetting 
activity from within it with no problem, so it is not Lilypond itself that 
seems to be the problem, but rather something specific to external applications 
calling it.

Is this a known issue? If so, any ideas on ways to fix it other than 
typesetting something and walking away for 20 minutes before it responds?

-Arle