> Indeed. Emacs actually got a preliminary port to the Boehm generational, incremental, mark-sweep collector many years ago, with a complete lack of interest in pursuing it.
Ja have a link? Asking because I've interacted with the devs and they are highly focused on getting emacs better. They would not reject it if it offered solid value.
Also you have a link to this Boehm collector you mention as the only one I know of is the conservative one and I'd like to know more. TIA
You may not believe the history, but you weren't there; I don't know how much is in mail archives. There was, for instance, a bizarre campaign to keep the charset `unification' out of Emacs 22. For some reason rms went along with that even when eval showed the argument was bogus.
That looks like the boehm GC, but Boehm is conservative. In no way is the Boehm GC that I'm aware of is generational or incremental (though it is mark-sweep).
"I was poking at alloc.c recently and realized that the existing conservative GC code is somewhat unsafe. In particular,
1) mark_maybe_pointer looks only for exact matches on object start. It's perfectly legal for the compiler to keep an interior object pointer and discard the pointer to the object start.
2) INTERVAL is GCed, but it's not represented in the memory tree: struct interval isn't a real lisp object and it's allocated as MEM_TYPE_NON_LISP. Even a direct pointer to the start of an interval won't protect it from GC. Shouldn't we treat intervals like conses?
We've been getting by on dumb luck and the magnanimity of the compiler."
I don't have time to go over the thread - conservative seems dodgy. I'll have to take your word for it. As for your main point, much to my surprise, you're right although I don't understand how, it doesn't match what I've read of it. No matter, you're right.
Slow in the same way that the conservative stack scanning was bound to leak. I did actually run Emacs with it after experience elsewhere.
Edit: I wonder how Boehm is somehow "most conservative", compared with, say, the Memory Pool System which I'd also look at these days but wasn't an option then.
I think it's an option, but I admit not one I was aware of. AFAIK the MP is a framework, and this is an option not the only way... but still, you're again!
Ja have a link? Asking because I've interacted with the devs and they are highly focused on getting emacs better. They would not reject it if it offered solid value.
Also you have a link to this Boehm collector you mention as the only one I know of is the conservative one and I'd like to know more. TIA