How to get maximum network speed between CT/VM?

dominikp

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Aug 28, 2018
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I thought that network speed between CT/VMs which nic's are bridged to one physical nic is only limited by cpu/sata/pcie things. But lately someone told me that itsnot that simple. Physical NIC speed, virtual drivers choice and additional settings are also matter.

So if i have:
- CT (ubuntu + NFS server)
- VM (ubuntu + e1000 driver + NFS client)
- both bridged to 1Gbit physical nic (some HP card)

... how to get maximum speed between them? Am i capped by 1Gbit or not?
 
good morning, try to doing some test with iperf3, i do using a vmbr1 on a SAN area network between two Proxmox Servers:

- No issues on performance network.

iperf3 Server ( iperf3 -s ):

Captura de Tela 2019-12-31 às 09.55.52.png

Iperf client (iperf3 -c "IP destination Server"):

Captura de Tela 2019-12-31 às 09.55.31.png

Network Interfaces:

Captura de Tela 2019-12-31 às 09.55.15.png

Captura de Tela 2019-12-31 às 10.02.54.png
 
You didnt undestand.
I was asking about CT/VMs ON THE SAME machine and THE SAME bridge. And the goal is to get more than 1Gb speed - by that i mean to get close as much as possible to native machine speeds where you copy file from one folder to another. This is limited only by sata/sas/raid speeds (and NFS in this particular case).
 
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Hi,

If you use virtio nic on a vmbr network the speed is limited by the CPU/Memory.
On a current CPU without load, you should get about 20-40 GByte/s
e1000 is software emulated nic and ist with about 30 MBit very slow.
 
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Same question here... I have plenty of VMs on ONE host... How I have to configure the connection between these VMs that they can transfer files with fullspeed (and not routing over network switch etc)?

All VMs have virtio nic drivers. I want to copy files within one VM from network share (openmediavault VM) to another network share (same openmediavault VM but other share). Speed is still max. of 110 MByte/s. I want to reach maximum SATA-Speed/HDD-Speed (210 MB/s).

Is that possible?
 
Last edited:
Review your overalll network config.
Review your IPs, they have to be in the same network.
Maybe you have a stuck with your router (if you have) and have only 1Gbps instead of 10Gbps.

I have between all VMs and VM - host 10Gbps uplink. I don't know why 10,but actually i have no more than 9.8Gbps with iperf3, however cpu load is not greater than 20% and mem not more than 40%. (host on ryzen9 3950x,vms have 3 vcpu and 6Gb ram )