Maximum speed for e1000 network card.

[labiol]

Situation:

* two HP blade server with FLEX (10Gbps) ethernet card ESXi 5u1.

* three virtual windows 2008 systems, e1000 network card

Last time I studied performance tab and network statistics on vCenter. The performance for network card was above 1Gbps. It was interested for me, because all my servers has e1000 (1Gb) network card installed

I made some test (using lan_speed-test and perfmon) and I discovered that the network card works a lot above 1Gbps.

I get above 5Gbps for os, when the windows works on the same ESXi server and about 2Gbps for windows placed on different ESXi (which is expected because my production network is limited to 2Gbps on flex card).

But the general question is, why I can get above 1Gbps network speed on e1000 card.

Regards

Kris

[Linjo]

This is the expected behavious, the advertised speed of the vNIC is not relevant since the transfer will be done in memory (on the same ESX) and over the 10G pNICS on different hosts.

// Linjo

[labiol]

So why the e1000 card is presented in operating system as 1Gb card and vmxnet3 as 10Gb card? Why Windows can use the 1Gb card with graeter speed. I undarstand that ESX can use full hardware/physical network card power but there is no limit in the operating system? Or it's because of vmtools?

[iw123]

Hi,

This might be worth a read for you i f you haven't come across it already: http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=100180...

There are other dfferences between the virtual adaptor types other than speed such as support for jumbo frames etc.

[labiol]

I know this article, but there is no explanetion about network speeds besides the 10Mbps for vlance. So the question is still open

[rickardnobel]

labiol wrote:

So why the e1000 card is presented in operating system as 1Gb card and vmxnet3 as 10Gb card?

That the e1000 is seen as a 1 Gbit Network Interface Card is likely because it emulates a certain real existing NIC (the Intel 82545EM), which almost all modern operating systems have a builtin driver for. As Linjo mentioned this does not limit the actual possible throughput.

Since the vmxnet3 adapter is a total madeup non-existing device it is more convenient to make it look like a 10Gbit adapter, since that removes some confusion.

[vGuy]

actually, the adapter with VM HW 8 is e1000e, nevertheless, as per my understanding the vNIC speed shown within the OS is irrelevant in the virtual word:

below is the excerpt from Pg 4. of VMware Networking Concepts paper:

"

The speed and duplex settings found in physical

networking are not relevant in the virtual network, because

all the data transfer takes place in the host system’s RAM,

nearly instantaneously and without the possibility of collisions or other signaling-related errors.

"

incase, if you want to limit the traffic for the VM traffic you can use traffic shaping at the portgroup layer OR port ID of vNIC (if using dvSwtich).

http://www.vmware.com/files/pdf/virtual_networking_concepts.pdf

[rickardnobel]

Obaid wrote:

actually, the adapter with VM HW 8 is e1000e

I have seen no one in the thread mention any specific VM Hardware version? Besides, the E1000E is only available to attach to a VM if it is running HW8 and the guest operating system is Windows 8.

For all other modern Guest Operating Systems the default is still E1000.

[vGuy]

I assumed HW 8 coz of vSphere5, but never realized the e1000e only supported above Win8, especially since 82574L drivers are included for Win2k8...thx for correcting, good to know!

[rickardnobel]

Obaid wrote:

I assumed HW 8 coz of vSphere5, but never realized the e1000e only supported above Win8, especially since 82574L drivers are included for Win2k8...thx for correcting, good to know!

It was a bit confusing when vSphere 5 was released and one of the new features that was presented was this new E1000E, however it was nowhere to be seen or available to be selected.. Just now in the latest updates with Win 8 support is it available in GUI.

It should be interesting to see if it performs any different than the original E1000.

[Linjo]

The performance should be about the same, the reason for the change is that Intel is not longer supporting the e1000 and the driver does not exist by default in Win8 and Server2012, the e1000e is supported and the driver is included with Win8 and Server2012

// Linjo

[labiol]

Thank for all respodns.

I undarstand that operating system (task manager) interprete incorectly network bandwich. For 1Gb card show 1Gb scale. The peacks is overscale.

The more trully statistics can be gathered from perfmon -> network interfaces etc. OK.

But why performance from vCenter (for particural virtual machine) shows me 1,2-1,4Gbps when the trully network traffic is above 5Gbps?

[Linjo]

vCenter does an average calculation over 5 min and get normalized over time so you probably do not get spikes there.

// Linjo

[rickardnobel]

labiol wrote:

But why performance from vCenter (for particural virtual machine) shows me 1,2-1,4Gbps when the trully network traffic is above 5Gbps?

If you want to study the network usage in more "real time" you could use the commandline tool ESXTOP in the "n" view. A bit hard to use at first, but there are many guides around the Internet.