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[juno-ovs-gre] low bandwidth for network node 10Gb nic (but around 3Gb/s only)

asked 2015-07-16 22:42:04 -0600

vuquangkha gravatar image

updated 2015-07-20 16:31:03 -0600

smaffulli gravatar image

Hi all,


I am using juno version, and neutron + openvswitch gre.

This is my diagram:

image description

Network node: external network, data network in a nic.

i tested bandwidth:

from physical network node to multiple physical compute node enough 10Gb/s. image description

But network node to multiple instance around 4Gb/s image description

And external server to multiple instance around 3Gb/s image description

(from network node to a instance enough 1Gb/s)

All not enough 10Gb/s

I searched multiple days, try MTU 9000,...

but can not, i don't know why.



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answered 2015-07-20 14:51:44 -0600

don gravatar image

I would set the MTU on both the eth* and the br-ex/tun/int bridges to 2000. The reason is, some network equipment has 3 buffer sizes: 0-64 bytes, 64-2K, 2K-9K. And the latter is much smaller.

Also, its not clear on what you are expecting. One host lists 10G, and the others 1G. Is it that the sum of the servers cannot exceed 3G and there are > 3 of them? Why would you expect Compute01 <-> Compute02 to be > 1Gbps? The show as having 1Gbps nic.

So is it these hosts > the world that is < 3Gbps?

Your diagram doesn't show what the blue-wire is, but make sure that switch also has 2K MTU [e.g. its not just eth2+br-ex, you need it on the switch ports as well].

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Thanks you for answer. I have 14 compute node, each compute node have a 1Gb nic. Network node have a 10Gb nic. But total throughput instance through network node to external network only around 3Gb/s i think similar (this link)

vuquangkha gravatar imagevuquangkha ( 2015-07-21 03:13:00 -0600 )edit

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Asked: 2015-07-16 22:42:04 -0600

Seen: 232 times

Last updated: Jul 20 '15