[pve-devel] win8r2 virtio net problems

[Daniel Hunsaker]

Ultimately, the Windows network stack is pretty terrible.  You'll get some
improvements from tweaking things (and it would be nice to have those
tweaks applied automatically wherever possible), but it'll never be near as
efficient as a Linux or BSD guest.  Microsoft hasn't done much with it
since they adapted it (poorly) from BSD's back around the time of NT4 (or
earlier), aside from fixing a few of the more major bugs.  Personally, I'd
avoid using Windows servers for anything network-heavy, whenever possible.
On Mar 29, 2014 9:36 PM, "Alexandre DERUMIER" <aderumier at odiso.com> wrote:

> I have done test with win2012 + virtio-net, no tuning, last virtio driver.
>
> on a small 2core 5110  @ 1.60GHz, I can achieve around 500mbit/s
>
> But the cpu is limiting the speed.  (so 500mbits vm<->host, or 250mbits
> vm<->vm)
>
> (seem that virtio-net windows use a lot more cpu than linux)
>
> I try to play with offloading to see if I can improve performance.
>
>
> ----- Mail original -----
>
> De: "Alexandre DERUMIER" <aderumier at odiso.com>
> À: "Dietmar Maurer" <dietmar at proxmox.com>
> Cc: pve-devel at pve.proxmox.com
> Envoyé: Samedi 29 Mars 2014 13:22:21
> Objet: Re: [pve-devel] win8r2 virtio net problems
>
> Hi, I never reach myself more than 900Mbits with windows guest. (2003 >
> 2012, any virito driver
>
> But 30mbit/s seem very slow.
>
> Maybe trying to play with disabling offloading options (in windows guest
> driver options) ? gro,gso,...
>
>
> ----- Mail original -----
>
> De: "Dietmar Maurer" <dietmar at proxmox.com>
> À: pve-devel at pve.proxmox.com
> Envoyé: Vendredi 28 Mars 2014 15:07:23
> Objet: [pve-devel] win8r2 virtio net problems
>
>
>
> Hi all,
>
> we just observed bad performance values with virtio network on win8r2
> guests.
>
> A simple iperf from a VM to the host shown about 700Mbit/s.
>
> Even worse, iperf between 2 win8r2 guests on the same bridge shown below
> 30Mbit/s.
>
> Using linux VMs, I am able to get > 9Gbit/s.
>
> I already made all optimizations suggested at:
>
> http://pve.proxmox.com/wiki/Paravirtualized_Network_Drivers_for_Windows
>
> Any ideas?
>
> _______________________________________________
> pve-devel mailing list
> pve-devel at pve.proxmox.com
> http://pve.proxmox.com/cgi-bin/mailman/listinfo/pve-devel
> _______________________________________________
> pve-devel mailing list
> pve-devel at pve.proxmox.com
> http://pve.proxmox.com/cgi-bin/mailman/listinfo/pve-devel
> _______________________________________________
> pve-devel mailing list
> pve-devel at pve.proxmox.com
> http://pve.proxmox.com/cgi-bin/mailman/listinfo/pve-devel
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.proxmox.com/pipermail/pve-devel/attachments/20140329/cb17bb70/attachment.htm>