[[!tag wishlist]]

[My ikiwiki instance](http://www.ipol.im/) is quite heavy. 674M of data in the source repo, 1.1G in its .git folder.
Lots of \[[!img ]] (~2200), lots of \[[!teximg ]] (~2700). A complete rebuild takes 10 minutes.

We could use a big machine, with plenty of CPUs. Could some multi-threading support be added to ikiwiki, by forking out all the external heavy  plugins (imagemagick, tex, ...) and/or by processing pages in parallel?

Disclaimer: I know nothing of the Perl approach to parallel processing.

> I agree that it would be lovely to be able to use multiple processors to speed up rebuilds on big sites (I have a big site myself), but, taking a quick look at what Perl threads entails, and taking into acount what I've seen of the code of IkiWiki, it would take a massive rewrite to make IkiWiki thread-safe - the API would have to be completely rewritten - and then more work again to introduce threading itself.  So my unofficial humble opinion is that it's unlikely to be done.
> Which is a pity, and I hope I'm mistaken about it.
> --[[KathrynAndersen]]

> > I have much less experience with the internals of Ikiwiki, much
> > less Multi-threading perl, but I agree that to make Ikiwiki thread
> > safe and to make the modifications to really take advantage of the
> > threads is probably beyond the realm of reasonable
> > expectations. Having said that, I wonder if there aren't ways to
> > make Ikiwiki perform better for these big cases where the only
> > option is to wait for it to grind through everything. Something
> > along the lines of doing all of the aggregation and dependency
> > heavy stuff early on, and then doing all of the page rendering
> > stuff at the end quasi-asynchronously? Or am I way off in the deep
> > end.
> >
> > From a practical perspective, it seems like these massive rebuild
> > situations represent a really small subset of ikiwiki builds. Most
> > sites are pretty small, and most sites need full rebuilds very
> > very infrequently. In that scope, 10 minute rebuilds aren't that
> > bad seeming. In terms of performance challenges, it's the one page
> > with 3-5 dependency that takes 10 seconds (say) to rebuild that's
> > a larger challenge for Ikiwiki as a whole. At the same time, I'd
> > be willing to bet that performance benefits for these really big
> > repositories for using fast disks (i.e. SSDs) could probably just
> > about meet the benefit of most of the threading/async work.
> >
> > --[[tychoish]]