Re: Against sqlite3!!!

[Alexandre Garreau]

Le merkredo, 8-a de decembro 2021, 7-a horo kaj 11:19 CET Arthur Miller a 
écrit :
> Lars Ingebrigtsen <larsi@gnus.org> writes:
> 
> 
> 
> > David Engster <deng@randomsample.de> writes:
> 
> 
> >> Yes, and it's slow. The Gnus registry is saved/loaded this way, and
> >> this has annoyed me for years.
> 
> 
> 
> > Yup.  The Gnus registry would be well suited to use sqlite directly,
> > though -- it's basically hand-maintaining a (large) database, and
> > sqlite is a good fit for that.
> > 
> > That is, I don't think the new normal persistence method would be
> > ideal
> > for the registry.
> > 
> > But, yes, the Gnus registry is a good demonstration of why serialising
> > hash tables to disk is unworkable in practice.
> 
> Than implement a way for Emacs to dump lisp objects to files faster. It
> would be very useful for Emacs in general.
> 
> You will still have to serialize your gnus db to sqlite db, and write it
> to disk via sqlite, so disk access will still be there.

Well, I think, wrt writes, it’s impossible to go faster than just writing 
plaintext.  But sqlite is here to make *reads* faster, not writes.  The 
only way I can see to make writes faster without any form of serialization 
is just garbage collecting related data together, and directly dumping 
memory onto disk, in a native but non-portable format, along with metadata 
about the native format, and specific implementations to decode it from 
other platforms for each memory format.  I’d love to see that.  But I 
think writing is not the bottleneck that we try to improve here.