Re: MPS: weak hash tables

[Gerd Möllmann]

Pip Cet <pipcet@protonmail.com> writes:

>> We could also expose ramp allocation to Lisp for these kinds of things,
>> so that one doesn't drive the collector nuts by allocating objects in
>> this manner.
>
> We can and should expose that, but probably not use it in this case.
> It might be worth it for large vectors, but for strings it probably
> won't help:
>
> Ramp allocation is only supported by AMC (Automatic Mostly-Copying).

Oh, didn't remember that. Then ramp allocation is pretty worthless.

We could park the arena temporarily though. I used that already for
dumping which similarly creates tons of objects, and it had a very
noticeable effect.

> I've decided to go ahead with the ugly non-bitfield patch, mostly for
> one reason: I'd really like to record previous and current addresses
> of moved objects somewhere, and the exthdr thing seems perfect for
> that--it lives in xmalloc'd memory so we can modify it from the scan
> function. Sorry it took such a lot of sleeping over it :-)
>
> So, last chance to object there.

Not me :-).