alvaropedroni
Enthusiast
Enthusiast

bandwidth problems on network cards, perhaps the workstation limit?

hello

I have many computer with windows10 + workstation 15 pro + nic 10GB + switch 10gb

example pc1 with 10gb nic + workstation 15 pro + storage nvme 3000Mb/s

example pc2 with 10gb nic + workstation 15 pro + storage nvme 3000Mb/s

my transfer speed between pc1 and pc2 is around 800MB / s =  80% of 10GB nic "this is perfect"

but if running windows 2012r2 (or another OS) on pc1 a running w2012r2 on pc2 the speed il maximun 80..50 MB/s when trasfert file.

I use vmxnet3 and windows see network speed to 10GB but speed is equal to nic 1GB

Now running both virtual machine on the same pc1 and speed when copy file is 80...50MB/s "in this case the workstation not use nic but move file on internel program workstation"

and therefore the speed should be 10Gb but is block to 80...50MB/s

My virtual nic is configure in brige mode with phisican nic:

vmnet0 - bridge - intel1 10GB

vmnet1 - bridge - intel2 10GB

etc

I suspect that workstation when using nic always considers them to be 1gb as a design limitation, and not real use the true band of nic 10gb

For example I discovered that the jumbo frame is not supported by the pro workstation and maximun mtu support is 1600 and not 9000

I can not find documentation of these limitations

Do you have any news about this? or ideas on how to unlock the limitations of the nic?

thanks

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2 Replies
Parveen1988
Enthusiast
Enthusiast

Hi There,

Interesting scenario. Could you let me know if the file transfer is between VM on PC1 and PC2 or between VM on PC1 and VM on PC2?

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alvaropedroni
Enthusiast
Enthusiast

1) transfer speed for file 40gb for pc1 to pc2:   800MB/s  (80% of 10GB)

2) transfer speed for fie 40gb for vm1 on pc1    to         vm2 on pc2:   50/80MB/s  (5-8% of 10GB)

3) transfer speed for 40gb for vm1 on pc1    to        vm2 on pc1  50/80MB/s  (5-8% of 10GB)

workstation pro 15 no use nic in this case but move traffic internal program on pc1

in example 3 it is evident that vmware does not use physical nic, but that low speed depends on the pro workstation 15

so it's not a hardware problem or computers is a problem of undocumented wmware limits, : vmware allows the maximum 1GB network traffic speed. but I must be sure that this is true or find a way to overcome this limit

thanks

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