What is the transmission rate between virtual machines connected to the same virtual switch?

[mkats]

Hi Guys,

I am trying to determine if the data transmission rate between virtual machines connected to the same virtual switch is equivocal to 10gb ethernet or faster.

Thanks

MK

[Troy_Clavell]

here's something worth checking out

http://communities.vmware.com/thread/199226

[jbruelasdgo · Accepted solution]

if it is the same vSwitch in the same ESX, should be bus speed

[VMmatty]

It should operate at bus speeds as others have said, but don't forget you have to account for the actual writing of that file to the disk. If both VMs are on the same iSCSI LUN (for example), then you are going to be limited to the speed of that connection. The same is true of any datastore type. Of course it will depend on what type of file you are copying or if you're streaming or performing some other kind of network operation.

[mkats]

Thank you Troy, the thread helped ouit. The discussion covered all the bases.

[mkats]

Thanks JB, That appears to be the consensus.

[mkats]

Good points, thank Matty

[mkats]

Alright Guys, Here are the netpef tests

Virtual Machine to Virtual Machine on the same physical host port to a virtual switch with two physical uplinks

TCP STREAM TEST to x.x.x.x

Recv Send Send

Socket Socket Message Elapsed

Size Size Size Time Throughput

bytes bytes bytes secs. 10^6bits/sec

8192 8192 8192 10.00 719.06

Virtual Machine to Virtual Machine on the same physical host ported to a virtual switch without any uplinks and jumbo frames enabled

TCP STREAM TEST to 10.10.10.1

Recv Send Send

Socket Socket Message Elapsed

Size Size Size Time Throughput

bytes bytes bytes secs. 10^6bits/sec

8192 8192 8192 10.00 0.31

[mkats]

Guys, my latest tests were at 2.16 Gbps and that is best I can do. I can honstely say it does not matter if its a dl380 g2 or a dl385 g5, with or without jumbo frames, or TSO.