Corpus wrote:
Running two Win2008 r2 64bit test VMs with E1000
In general it is good to use the VMXNET3 adapter which is more optimized.
Making the parameter change to the cmd-line as sugested here, did the trick.
Why does windows make such poor performance in this test case? Can it be that this also applies to some file transfers and other network traffic as wel?
The iperf test might be somewhat "constructed" making the default Windows TCP behavior need to be tweaked with different options to have it open several sessions to be able to push through large amount of data.
However, it could be interesting to actually test some native Windows networking, like for example copy a large file from a VM to another and just watch in Task Manager what kind of bandwidth you get. (Do check that the storage will not be the bottleneck however.)