Fix calcMem for Vulcan
Fix calcMem for Vulcan

Fixes #39
vishr/go-http-routing-benchmark,sunisdown/go-http-routing-benchmark,twanies/go-http-routing-benchmark,julienschmidt/go-http-routing-benchmark,wmydz1/go-http-routing-benchmark,Waynelilns/go-http-routing-benchmark