Ideas

Member senf::Packet::annotation ()

Pool the annotation vectors: In the destructor swap the vector into a vector graveyard (swapping two vectors is an O(1) no allocation operation). In the constructor, if there is a vector in the graveyard, swap it in from there. Of course, it would be better to do away with the vector and just allocate the space together with the packet but that looks quite complicated to do ... especially considering that the packetimpl itself uses a pool.