Re: ARC vs Manual Reference Counting
Re: ARC vs Manual Reference Counting
- Subject: Re: ARC vs Manual Reference Counting
- From: Jens Alfke <email@hidden>
- Date: Tue, 10 Sep 2013 21:04:34 -0700
On Sep 10, 2013, at 12:33 PM, Dave <email@hidden> wrote:
> You with all this talk of memory management, you'd think that Apple (or someone) would have come up with a hardware solution for this by now. In the 70's and 80's I worked on some firmware and hardware that would handle garbage collection in real time (with a little help from OS Software).
I’ve read through a lot of GC papers in the past, and I’m not sure what you’re talking about here, unless it’s something that allows extra tag bits to be stored in pointers. This was used a lot in old LISP systems; it can be useful with interpreted languages but I don’t think it’d be applicable to a C-based language. (A lot of the more sophisticated GC techniques simply don’t work with C-like code because it’s too low-level and makes too many assumptions about memory. For example, you can’t use compaction or copying collectors at all because objects can’t be relocated. The Obj-C garbage collector had to rely on inefficient conservative mark/sweep algorithms.)
> If Apple were to implement something like this I think there would be a massive increase in performance and reliability
Nothing personal, but I think you’re falling into the common fallacy of thinking that Apple engineers are naive and/or ignorant. It happens all the time on these lists. In general, you should assume that the people working on system software are pretty damn smart and experienced, and are aware of all the techniques that an interested but non-expert outsider would know of. If they’re not using them, there’s probably a good reason for it.
(This is a special case of the nearly universal engineer’s fallacy of dismissing any problem you haven’t personally worked on as trivial.)
—Jens
_______________________________________________
Cocoa-dev mailing list (email@hidden)
Please do not post admin requests or moderator comments to the list.
Contact the moderators at cocoa-dev-admins(at)lists.apple.com
Help/Unsubscribe/Update your Subscription:
This email sent to email@hidden