Network Speed Issues

[donkeh]

Hi all,

I've just started looking at proxmox with a view to switching from vmware esxi.

I have so far implemented a single node (Intel Xeon E31220 Quad Core @ 3.10Ghz, 16Gb Memory and 500Gb Disk), and also a FreeNAS iscsi target.

I have two virtual machines setup, both running Server 2008 R2, one residing on the node's local disk and the other residing on the NAS.

The VM which resides on the NAS, was first brought up on the local disk and then backed up and restored to the NAS. The copying process of the VM pushed the network speed to over 600Mb/s, which while it isn't quite Gigabit speed, is reasonable.

My issue starts inside my VM's. Downloading from a source on the local network (but connected at 100Mb/s), both VM's can only achieve a maximum download speed of around 3.2Mb/s.

On both virtual machines, I have tried the Realtek, the Intel and the Virtio network card types. I have also tried multiple protocols to make sure it wasn't overhead in the protocol.

The same hardware using esxi, is able to achieve expected network throughput.

Any suggestions please ?

Thanks,

Leon

 

[spirit]

My issue starts inside my VM's. Downloading from a source on the local network (but connected at 100Mb/s), both VM's can only achieve a maximum download speed of around 3.2Mb/s.

Are you sure that you are not in half-duplex ?

 

[donkeh]

Are you sure that you are not in half-duplex ?

Hi,

The host shows as being connected at..

eth0: negotiated 1000baseT-FD flow-control, link ok

I'm not sure there is a way in Windows to confirm ?

Leon

 

[donkeh]

Apologies for any delayed replies - seems I am currently under moderation as a new user.

I should add that I have created a linux kvm, which can download at expected speeds from the same source.

Leon

 

[spirit]

eth0: negotiated 1000baseT-FD flow-control, link ok

so you are connected in Gigabit ? Because you said 100MB in your post .

 

[donkeh]

so you are connected in Gigabit ? Because you said 100MB in your post .

The source from where the file is provided is connected only at 100Mb because it does not have Gigabit port.

 

[spirit]

oh, ok sorry.

And you get only 3.2Mb/s ? (so 400KB/s ?)

How much do you get between your host and your 100Mb/s source ?

 

[donkeh]

oh, ok sorry.

And you get only 3.2Mb/s ? (so 400KB/s ?)

How much do you get between your host and your 100Mb/s source ?

Sorry, the windows hosts achieve 3.2MB/s.

Between host and source, can achieve 10+MB/s.

Between linux KVM and source, can achieve 10+MB/s

Thanks,

Leon

 

[spirit]

try to tune your windows vm registry:
http://www.linux-kvm.org/page/WindowsGuestDrivers/kvmnet/registry

use virtio with last drivers
http://alt.fedoraproject.org/pub/alt/virtio-win/latest/images/bin/virtio-win-0.1-52.iso

I can achieve around 600-700mb/s with my windows guest.

 

[ebiss]

try to tune your windows vm registry:
http://www.linux-kvm.org/page/WindowsGuestDrivers/kvmnet/registry

use virtio with last drivers
http://alt.fedoraproject.org/pub/alt/virtio-win/latest/images/bin/virtio-win-0.1-52.iso

I can achieve around 600-700mb/s with my windows guest.

Thanks. mark

 

[donkeh]

Thanks for the suggestions - I have already followed some of them, but will take a look a little more.

I'm also going to stick a machine on the same network with gigabit connection, to see how that performs.

I did do another test, which was to download a file to the windows vm (located on local storage) from a linux vm (also on local storage) and this resulted in download speed of 30MB/s.

Not sure what I should expect to achieve intra-vm ?

Leon

 

[donkeh]

I seem to have cured this problem, although not really sure how.

I am now getting reasonable speeds of 400-600mb/s, and of my 2 test windows machines, I have applied the tuned settings to one machine but not the other.

I'll continue on with my PoC and see how it behaves - thanks for the suggestions.

Leon