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Re: ObjC configured --with-objc-gc needs external Boehm gc


Jeff Sturm wrote:
> Can you say much slowdown is due to the use of thread primitives in libobjc vs.
> how much is due to memory allocation?  Using boehm-gc might even be beneficial
> to the threaded runtime... I've observed poor performance from the standard
> (thread-safe) allocator on some systems, including glibc.

No, unfortunatly I can't, I didn't make any memory timings (except with
mingw32, where the default allocator is *extremly* slow).

If this is of interest to you, one major problem with the (GNU) libobjc
is that all operations referring class objects by name are compiled to
hashtable lookups instead of static references, eg

  [NSString alloc]

ends up int
  objc_msg_send(objc_class_lookup("NSString"),@sel(alloc));

And this objc_class_lookup is protected by a mutex ...

best regards
  Helge
-- 
SKYRIX Software AG  http://www.skyrix.com/

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