Rust implementation too slow

[akhilsb]

I was looking at the CPP implementation of Glow-DVRF beacons at https://github.com/fetchai/research-dvrf/, which takes ~ 4 milliseconds per beacon generation(n=4,t=2) on an 8-core Ubuntu 20.04 machine. The rust implementation of the current repository takes around 25 milliseconds per beacon generation for the same config. Any potential reasons that I should be wary of?