Re: [Chicken-hackers] [PATCH] Fix performance bottleneck in compiling large files, add profiling option

[Felix]

> 
> The attached patch adds this cutoff point, and provides for a compiler
> switch to tweak this limit (and disable it by passing in 0)
> This seems to produce mostly linear output and scales all the way
> up to 10.000 trivial toplevel forms without breaking a sweat.  See
> the nesting-settings.png for a comparison of what happens when using
> a limit of 10, 100 and 0.
> 
> At 3000 forms, the compilation time is 5 seconds on my laptop versus
> 45 seconds without the limit.
> 
> I think this option is generally useful since if the compiler reports
> a procedure nesting depth of more than about 10, this rapidly becomes
> useless to a user (it also reports procedure nesting when the
> scrutinizer finds a possible type error).
> 

Thanks for the patch and the investigation of this problem. I must
say that I would find such an option rather obscure. Couldn't we simply
do a cutoff, probably preserving starting and ending elements of the
nesting list?, in other words:

  "FOO in BAR in ... in YES in NO in PERHAPS" ?

With (say) 10 elements at the front and the back this should be more
than sufficient.


cheers,
felix