> Under boost_1_36_0\libs\serialization\example there are some hpp and
> cpp files for portable binary format (portable_binary_archive.hpp,
> portable_binary_iarchive.cpp ...) and I am wondering how performant
> the code is.

This was actually tested on various platforms of different 32/64 endian
combinations.  And the test consisted of running ALL serialization
tests as is done with the "official" archive implementations.  To me,
the main proble is that its missing support for floating point types.
Including such support in a definitive, portable manner would
be a significant effort which so far no one has deigned to undertake.