Wanderlust speed [was: About Wanderlust threading]

[Juliusz Chroboczek <jch@pps.univ-paris-diderot.fr>]

> vi/m guy for 20+ years.  Only been using Emacs for a couple

That's okay -- all is forgiven.

>> Heh.  It's not the ELisp that's a problem, it's elmo and wl, which
>> seem designed to handle tens of thousands of messages on a pocket
>> calculator.  Some of the micro-optimisations are impressive.

> True, that.  Wanderlust is by far the most capable mua I've ever used
> when it comes to handling high volume.

Certainly not.  Trojitá[1] or even the venerable Pine are way more
responsive than Wanderlust on large mailboxen.

The way these mailers work is that they never actually compute a full
summary -- they only compute the part of the summary that is visible
at a given time.  As you scroll through the summary, other parts are
computed as they become visible.  (Trojitá adds background prefetching
and an elmo-style cache -- try it on a large folder sometime, you'll
be impressed.)

Where Wanderlust certainly shines is in the amount of work that it
manages to cache -- have a look at one of the .wl-summary-cache files
under ~/.elmo at some point, you'll be suprised.  Unfortunately, that
code is complex, undocumented, and there doesn't appear to be any
automatic cache management -- you need to either insert cache
invalidation code at the right points, or require the users to type
"s all" or "C-u ." when they change something.

>> (Seriously, though -- I'm sure there's people willing to contribute,
>> but we need a stable, maintained repository that is regularly pushed
>> into the package repositories.)
>
> I think Erik is pretty close to making this happen, no?

(Crosses fingers and starts hacking.)

-- Juliusz

[1] http://trojita.flaska.net/