Network performance issues

[cbos@sth.nu]

Hello all,

I have two KVM Windows quest on the same ProxMox host.
The network between the quests are very slow.

This is my configuration:
[CODEroot@host:~# pveversion -v
pve-manager: 2.3-13 (pve-manager/2.3/7946f1f1)
running kernel: 2.6.32-18-pve
proxmox-ve-2.6.32: 2.3-88
pve-kernel-2.6.32-16-pve: 2.6.32-82
pve-kernel-2.6.32-18-pve: 2.6.32-88
pve-kernel-2.6.32-17-pve: 2.6.32-83
lvm2: 2.02.95-1pve2
clvm: 2.02.95-1pve2
corosync-pve: 1.4.4-4
openais-pve: 1.1.4-2
libqb: 0.10.1-2
redhat-cluster-pve: 3.1.93-2
resource-agents-pve: 3.9.2-3
fence-agents-pve: 3.1.9-1
pve-cluster: 1.0-36
qemu-server: 2.3-18
pve-firmware: 1.0-21
libpve-common-perl: 1.0-48
libpve-access-control: 1.0-26
libpve-storage-perl: 2.3-6
vncterm: 1.0-3
vzctl: 4.0-1pve2
vzprocps: 2.0.11-2
vzquota: 3.1-1
pve-qemu-kvm: 1.4-8
ksm-control-daemon: 1.1-1[/CODE]

iperf from host to quest1, looks okay

root@host:~# iperf -c 192.168.0.2                       
------------------------------------------------------------
Client connecting to 192.168.0.2, TCP port 5001
TCP window size: 23.8 KByte (default)
------------------------------------------------------------
[  3] local 192.168.0.5 port 59380 connected with 192.168.0.2 port 5001
[ ID] Interval       Transfer     Bandwidth
[  3]  0.0-10.0 sec  2.34 GBytes  2.01 Gbits/sec

iperf from quest2 to quest1, bad :-(

C:\Users\sth\Desktop\iperf>iperf.exe -c 192.168.0.2
------------------------------------------------------------
Client connecting to 192.168.0.2, TCP port 5001
TCP window size: 64.0 KByte (default)
------------------------------------------------------------
[  3] local 192.168.0.3 port 49276 connected with 192.168.0.2 port 5001
[ ID] Interval       Transfer     Bandwidth
[  3]  0.0-10.1 sec  17.4 MBytes  14.4 Mbits/sec

when choose for TCP Window size 64k, it's okay

C:\Users\sth\Desktop\iperf>iperf.exe -c 192.168.0.2 -w 64k
------------------------------------------------------------
Client connecting to 192.168.0.2, TCP port 5001
TCP window size: 64.0 KByte
------------------------------------------------------------
[  3] local 192.168.0.3 port 49280 connected with 192.168.0.2 port 5001
[ ID] Interval       Transfer     Bandwidth
[  3]  0.0-10.0 sec  1.69 GBytes  1.45 Gbits/sec

Both quest have a virtio network card om bridge vmbr0

Quest1:

root@host:~# cat /etc/pve/nodes/host/qemu-server/100.conf
bootdisk: ide0
cores: 8
ide0: StorVMs01:vm-100-disk-1,cache=none,size=450G
ide2: none,media=cdrom
memory: 24576
name: SBS01
net0: virtio=5A:2D:B2:D7:AE:19,bridge=vmbr0
onboot: 1
ostype: win7
sockets: 2

Quest 2:

root@host:~# cat /etc/pve/nodes/host/qemu-server/101.conf  
bootdisk: ide0
cores: 8
ide0: StorVMs01:vm-101-disk-1,cache=none,size=150G
ide2: cdrom,media=cdrom
memory: 16384
name: TS01
net0: virtio=22:8F:98:A0:B8:47,bridge=vmbr0
ostype: win7
sockets: 2
virtio1: StorVMs01:vm-101-disk-2,cache=none,size=50G

What's wrong or what do I wrong?

Christiaan

 

[dietmar]

Do you have 16 cores (2 sockets, 8 cores) on the host node?

 

[cbos@sth.nu]

Do you have 16 cores (2 sockets, 8 cores) on the host node?

No, the server have 1 CPU (socket), 6 cores = 12 thread

Now, I have quest1 and quest2 gives 1 socket and 6 cores. And tested it again.
But the outputs are the same.

Do you have another suggestion?

Christiaan

 

[dietmar]

You wrote: "when choose for TCP Window size 64k, it's okay"

But 64k window size is the default anyways?

 

[cbos@sth.nu]

But 64k window size is the default anyways?

C:\Users\sth\Desktop\iperf>iperf.exe -c 192.168.0.2
------------------------------------------------------------
Client connecting to 192.168.0.2, TCP port 5001
TCP window size: 64.0 KByte (default)
------------------------------------------------------------
[  3] local 192.168.0.3 port 57695 connected with 192.168.0.2 port 5001
[ ID] Interval       Transfer     Bandwidth
[  3]  0.0-10.1 sec  16.9 MBytes  14.1 Mbits/sec

C:\Users\sth\Desktop\iperf>iperf.exe -c 192.168.0.2 -w 64k
------------------------------------------------------------
Client connecting to 192.168.0.2, TCP port 5001
TCP window size: 64.0 KByte
------------------------------------------------------------
[  3] local 192.168.0.3 port 57705 connected with 192.168.0.2 port 5001
[ ID] Interval       Transfer     Bandwidth
[  3]  0.0-10.0 sec  1.77 GBytes  1.52 Gbits/sec

Yes, it say, it is the default size. Is it really?
I can explain the different.
Is it possible to set de tcp window size in Windows?