What is the purpose of split info files?

[Stefano Lattarini]

Hello everybody.

In Automake, the need to support split '.info' output files adds some
annoying complexity in several places; and for backward-compatibility,
that is sadly bound not to change, surely not in the near future, and
probably not even in the distant one.

But in the Automake-NG fork we are breaking backward compatibility in
several places already, so I'd like to grab the occasion and get rid of
the support for split info files there.  But I'm not sure if this would
be a good move, because I'm not aware of what the purpose of splitting
info files in the first place.  Is that done for performance or memory
saving reasons (which I assume were relevant in the past, but that,
with today's powerful machines, will get less and less important in the
future, shrinking to irrelevance soon enough)?  Or is there some more
subtle and fundamental reason?

Thanks,
  Stefano