HPKP only consists of an additional check which compares the fingerprint of the public key in the certificate against a known value. This is a very cheap operation compared to all the other operations which need also to be done on a full TLS handshake, like:
- validating the certificate chain is more expensive than checking the fingerprint only
- key exchange is way more expensive then validating the certificate chain
- and the costs of communication are usually way higher unless you have a low-latency connection or a very slow CPU
In summary: you will probably not be able to measure any performance impact caused by HPKP.