id summary reporter owner description type status milestone component version severity resolution keywords cc 4228 Associative containers performance Domagoj Šarić Joel de Guzman "The Boost.Fusion documentation states that associative containers provide efficient key-based access while this seems not to be so in reality (AFAICT the associative containers actually use vectors for their implementation). As reported in this post http://lists.boost.org/Archives/boost/2010/05/166358.php I have achieved meassurably better compile-time performance when using plain fusion::vectors with linear searches than with fusion::maps. Attached are two simple tests that try to demonstrate this (Steven Watanabe's template profiler 'says' that both approaches yield the same number of template instantiations). The reason that in my real life (much more complicated) project I get not only same but better performance with vectors might perhaps be that the find<> (linear search) on the 'main vector' might already be 'cached'/instantiated by some other operation." Bugs new Boost 1.43.0 fusion Boost 1.44.0 Optimization