Hello all.

We are moving from Xenserver 6.5 environment to KVM because we can't use 10gbe speed in our VM's so we decided to test KVM.

To inicial test I've create script, using qemu commands, to build two VM's and test the nic speed.

Each VM has one nic, using virtio, into it own bridge. In this bridge we associate one 10gbe physical nic.

They can communicate each other.

When we try do a copy, through SCP, the speed is 300mbps. And if we open another copy this speed been the half.

What we are using:

S.O:

CentOS 7

Kernel 3.10.0-123.el7.x86_64

qemu-kvm.x86_64 10:1.5.3-60.el7

libvirt-daemon.x86_64 1.1.1-29.el7

Hardware:

Dell PowerEdge R720

16GB RAM

2TB SAS

Two Broadcom Corporation NetXtreme II BCM57810 10 Gigabit

Command to start VM's:

/usr/libexec/qemu-kvm -m 1024 -enable-kvm -k en-us -hda teste1.img -net nic,model=virtio,macaddr=00:01:02:aa:bb:cc -net tap,ifname=tap1,script=no,downscript=no -vnc :0

What Do I doing wrong?

Is my test right?

Is my interpretation right?

Is my enviroment correct?

Can I improve or fix any think with my libvirt or command arguments?

Best regards

Atenciosamente,

Kalil de A. Carvalho