Im running 5 Mbits mid node on Pi3. Cpu load is 25-30% on 1 core with full steady traffic - no aes-ni here. <br />Things should improve greatly when this ticket will go live in 0.2.9.x<br /><a href="https://trac.torproject.org/projects/tor/ticket/7572">https://trac.torproject.org/projects/tor/ticket/7572</a>