Am 06.02.2014 12:37, schrieb Max Klyga:
Anti-GC crowd tries to promote ARC as an deterministic alternative for
memory management.
I noticed that people promoting ARC do not provide any disadvantages for
proposed approach.
The thing is in gamedev and other soft-realitime software background
only a handfull types of resources are really managed by RC and memory
usage patterns are VERY specific to their domain (mostly linear
allocation/deallocation and objects with non deterministic lifetime are
preallocated in pools).
Trying to use RC as a general method of memory management leads to some
problems.
A pretty detailed view by John Harrop (He is somewhat known for trolling
in PL community, but nonetheless knows what he is talking about) -
http://www.quora.com/Computer-Programming/How-do-reference-counting-and-garbage-collection-compare/answer/Jon-Harrop-1?srid=3Gvg&share=1#
So RC could also introduce unpredictable pause times at undesired places.
This is also confirmed by research from HP -
http://www.hpl.hp.com/personal/Hans_Boehm/popl04/refcnt.pdf
My point is that we should not ruin the language ease of use. We do need
to deal with Phobos internal allocations, but we should not switch to
ARC as a default memory management scheme. In practice people promoting
ARC will probably not use phobos anyway. Currently its just an excuse to
not use D.
Look at c++ and STL, etc. People will roll their own solutions no matter
what you try.
Full ACK! Reference counting should be well supported, but it shouldn't
be the default scheme or built-in at a low level. From my personal
experience it would be ideal to be able to customize certain types to be
reference counted (allowing the user full flexibility implementing the
actual reference counting and without ruling out weak references!), but
have them accessible using the same syntax and type conversion semantics
as normal references.
