The good news is that lxc is almost the same as native considering performance tests!
Comparing with the VM (kvm), we have some basic results here:
CPU:native(lxc)and vm are almost the same
MEM:VM performance is about 1/2 of native (lxc)
DISK:VM write performance is 2/3 of native, read performance 1/2
NETWORK:VM has twice network latency than native