After installing a wired gigabit network in my house, due to the WIFI being bogged down by 14 wireless clients, I tested the performance in the network. I got around 500-600MBit/sec in read speeds and about 600-700MBit/sec in write speeds. But when I tried against the Amahi server I found that I only got 56MBit/sec in read speeds.
After looking at the samba configuration file I saw that Async IO ('''AIO''') was not enabled by Amahi. What AIO does is that it let's Samba create multiple threads to handle several file operationsasynchronously. This can, at the expense of some CPU cycles, increase the performance quite a lot.
I increased the read speed to 500-600MBit/sec by enabling AIO and saw Samba using around 1-4% CPU on a Intel E2200.