Strange network issue on Win7 Guest

[bigmo]

Hello,

i use Proxmox on a dedicated server and iam running a windows 7 machine as guest.
The server is connected over gigabit and the guest has the virtio network card. From both, the guest and the host i transfer files to my home.
When transfering files from the host then i get full speed of 50Mbits (my home connection is 50Mbits) but when transfering files from the guest to my home pc over ftp the speed per transfer stucks at 15Mbit/s
If i transfer a second file simultan the second file also gets 15Mbits, so the connection seems not to be the problem. But why the speed stucks at 15Mbit per thread?

Someone any idea?

 

[wolfgang]

Hi,
What nic type do you are using?

 

[bigmo]

Hello Wolfgang,

in the host there ist a rtl8168f present.

Here you can see what i mean....

iperf from the host
xxx@xxx:~$ iperf -c xxx
------------------------------------------------------------
Client connecting to xxx, TCP port 5001
TCP window size: 19.6 KByte (default)
------------------------------------------------------------
[ 3] local xxx port 37399 connected with xxx port 5001
[ ID] Interval Transfer Bandwidth
[ 3] 0.0-10.0 sec 54.5 MBytes 45.6 Mbits/sec


iperf from the W7 guest:
C:\Users\xxx\Desktop\iperf>iperf -c xxx
------------------------------------------------------------
Client connecting to xxx, TCP port 5001
TCP window size: 63.0 KByte (default)
------------------------------------------------------------
[ 3] local xxx port 56815 connected with xxx port 5001
[ ID] Interval Transfer Bandwidth
[ 3] 0.0-10.1 sec 21.9 MBytes 18.2 Mbits/sec