I'm launching a rsync simple command between two servers. Both servers have two eth interfaces on bonding. When I send a big file from one server to the other with rsync I reach 130M/s transfer rate.
But, and here is the problem, when I send a directory with lots of small files the transfer is 1M/s at its best.
I've checked both cpu loads(8cpu i7), and they are at 10% maximum.
Knowing that what makes all the transfer slow down is the open/close of the files, and this 'theoretically' goes on the cpu, I understand that this can be easily tuned. But I do not know how to tune that.
Any tip on how to make rsync use all CPUs?