Re: Enlarge MAX_ALLOCA?

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

>> It makes the potential max increment of stack space "per
>> lisp-eval-depth" larger, and hence increases the risk that we'll eat up
>> our stack before we bump into max-lisp-eval-depth.
> Which functions relevant to max-lisp-eval-depth use SAFE_ALLOCA?

I don't know.  Maybe none, but that would surprise me.

>> I think it makes a lot of sense to try and allocate this space on the
>> stack when decoding file names, but why does it allocate such a huge
>> buffer just to en/decode a puny file name?
> That buffer is fixed in size, I don't know why.  Perhaps it's hard to
> know in advance how much we will need.

Supposedly, every coding system comes with a "blow up factor" (can't
remember the name we use) which should be usable to compute a safe
upper-bound.

> I hope Handa-san could explain.

Handa?

> Again, the problem is memory fragmentation and the resulting large
> footprint, not the cost of the allocation.

Is this memory fragmentation problem hypothetical, or have we seen
evidence of it?


        Stefan