Re: Native display of line numbers

[Stefan Monnier <monnier@iro.umontreal.ca>]

> nlinum performed so poorly in my benchmarks that I was ashamed of
> publishing the data.  The benchmark entails scrolling through xdisp.c
> one line at a time.

Oh, yes, I think this is the case where there are too many overlays.
There's hope that the new tree-based overlays representation would solve
this problem, but I haven't actually checked.

There are also other ways to circumvent this performance problem, by
flushing the undisplayed overlays every once in a while.  I have some
code for that in nlinum.el, tho it's commented out, because it ends up
triggering re-fontification of the code later on (because currently
jit-lock can't be told to refresh nlinum without also refreshing all
other clients such as font-lock).  It'd be good to improve jit-lock so
this can be done better, but clearly this is one of those cases where
the more you progress, the more work you have to do.


        Stefan