Is it possible to implement lock free map in C++

Question

We are developing a network application based C/S, we find there are too many locks adding to std::map that the performance of server became poor.

I wonder if it is

Answer 1

HashMap would suit? Have a look at Intel Threading Building Blocks, they have an interesting concurrent map. I'm not sure it's lock-free, but hopefully you're interested in good multithreading performance, not particularly in lock-freeness. Also you can check CityHash lib

EDIT:

Actually TBB's hash map is not lock-free