PXE issues

Hi,

I have the following issue with KVM and PXE booting:

System:

    CPU: Intel(R) Core(TM) i7-3770K
    KVM version: 1.1.4-1
    Kernel version: 3.11.6-1
    Arch: x86_64

Environment setup:

One ASUS router with DHCP on it
Guest 1: Windows 2008 R2 Core
Guest 2: Windows 2008 R2 Standard with Windows Deployment Services Guest 3: No OS installed, booting from network (PXE)

All servers have RTL8139 device model set for the NIC and the
network setup for KVM is bridged. The network conneciton is stable for all my virtual machines, but when I try to boot from the network the data transfer between Guest 2 and Guest 3 is poor. I did some investigation using wireshark on Guest 2 and it shoed that the Guest 3 has trouble responding to the TFTP packets sent by Guest 2.
I switched the device model for these 3 guests machines to virtio,
installed drivers on guest 1 and 2 and retried the process; the result was even worse that above. I made a calculation about the time it took to download a 3MB file (boot.sdi) and the result was about 12 hours, and the next file to download is about 1BG (that will take me several days).

In both cases guest 3 response with acknowledgement packets is very slow; guest 2 sends 5 to 10 data information between guest 3 responses and until it has responded to all guest 2 will resend the packets resulting in poor data transfer rate.

-- bug decription end ----

Any suggestions where I should post this bug?

Best regards,
Catalin Boldan.