id	summary	reporter	owner	description	type	status	milestone	component	version	severity	resolution	keywords	cc
4307	basic_oarchive optimization	anonymous	Robert Ramey	"attached are patches that optimizes memory allocation and runtime complexity of basic_oarchive.
it should not change any serialization behaviour, and archives by the patched basic_oarchive can be read by the unpatched basic_iarchive.

what the patch does in detail:
 - replace log(O) lookup of ""cobject"" class info for each
   serialized class with a log(1) vector lookup. avoids
   container node allocation.
 - replace log(O) lookup of ""aobject"" object tracking info
   with log(1) hashing. avoids container node allocation.
 - use allocation pools for ""aobject"" object tracking info
 - store whether a class was stored as a pointer inside
   the ""cobject"" class info, to remove std::set stored_pointers

before:
 - 4 allocations on construction
 - 1 allocation for each serialized class, tracked or not
 - 1 allocation for each tracked object
after:
 - 1 allocation on construction(PIMPL)
 - no allocation for classes if less than 256 classes are serialized.
   1 allocation for 512 classes, 2 for 1024, ...
 - no allocation for object tracking if less than 256 objects are serialized.
   after that, about 1 allocation for 16 tracked objects
"	Patches	new	Boost 1.43.0	serialization	Boost 1.44.0	Optimization