Intel 82576 Gigabit on Debian 7 slow speed.

[Mimiko <vbvbrj@gmail.com>]

Hello.

I've bonded two onboard Intel 82576 Gigabit networks on an supermicro 
server for load balancing (round-robin). It is working, but transfer 
rate is about 10-20MB/s, while on same type of server the same 
configuration in windows I get around 100MB/s.

cat /proc/net/bonding/bond0
Ethernet Channel Bonding Driver: v3.7.1 (April 27, 2011)

Bonding Mode: load balancing (round-robin)
MII Status: up
MII Polling Interval (ms): 100
Up Delay (ms): 200
Down Delay (ms): 200

Slave Interface: eth0
MII Status: up
Speed: 1000 Mbps
Duplex: full
Link Failure Count: 0
Slave queue ID: 0

Slave Interface: eth1
MII Status: up
Speed: 1000 Mbps
Duplex: full
Link Failure Count: 0
Slave queue ID: 0

I've tried disable bond and leave only eth0, same result. I've tried to 
update to backported newer kernel with no success. Copying with via ssh 
is same speed. If lots of users starts to use the samba shares, even ssh 
lags.

What could be the problem?

Thank you.