[Samba] Full duplex read/write performance

[Hans-Kristian Bakke]

Hi

I have a setup where I regularily read from one share, process the
data, and write them back to another share, on the same samba server.
The issue I am seeing is that the speed levels out at about 55 MB/s,
or around 500 mbit/s in both directions.

The interesting thing is that if I create a KVM guest on the same
server with pass through to the same hard drives to host the share
that I read from I reach around 110 MB/s to the destination share
after a few seconds. In other words I then get full duplex gigabit
speeds from the fileserver.

Why is that? Is this the result of running samba in two different
processes (host and VM), and hence be able to process both reads and
writes in a parallell way?

Is there some way to make a single samba server process data at
1gbit/s read and write at the same time for two different shares, like
I can do if I put one share in a VM on the same host?

If I only do copies or writes in one direction from my workstation I
always max the gigabit at ~110MB/s.


// H-K