I am going to pass data up/down a 5-10 layered object using signals and slots. Which should result in a few thousand signal per sec. Which is far form "I clicked a button". All my object will also signal them self on a timer about every 100ms so they can do some processing.
What would be the fastest C++ Signal/Slot implementation which would be small and not require other library such as boost. (I need to keep the total size of my Binary very small).
I have seen libSigC++, sigSlot, Cpp-Events,
Often signal libraries are designed for ease of utilization, and not with a heavy performance in mind. You can check this article maybe helpful while pursuing fast execution.
In your case I'd start trying the more simple, like sigslot. But I'd not use a signal library under such circumstances... probably some kind of message queue, with a time stamp of some kind.
Even most complex and feature-rich signal/slot libraries are quite lightweight. The speed of signal emitting is in most cases comparable to virtual function call. In case of template-driven libraries such as boost::signals and libsigc++ you get essentially the same performance as you'd get passing function pointers around.