Open Stack

Hi Rick,

On 25 October 2013 13:44, Rick Jones <rick.jones2 at hp.com> wrote:

> On 10/25/2013 08:19 AM, Martinx - ジェームズ wrote:
>
>> I think can say... "YAY!!"    :-D
>>
>> With "LibvirtOpenVswitchDriver" my internal communication is the double
>> now! It goes from ~200 (with LibvirtHybridOVSBridgeDriver) to
>> *_400Mbit/s_* (with LibvirtOpenVswitchDriver)! Still far from 1Gbit/s
>>
>> (my physical path limit) but, more acceptable now.
>>
>> The command "ethtool -K eth1 gro off" still makes no difference.
>>
>
> Does GRO happen if there isn't RX CKO on the NIC?



Ouch! I missed that lesson...  hehe

No idea, how can I check / test this?

If I "disable RX CKO" (using ethtool?) on the NIC, how can I verify if the
GRO is actually happening or not?

Anyway, I'm goggling about all this stuff right now. Thanks for pointing it
out!

Refs:

* JLS2009: Generic receive offload - http://lwn.net/Articles/358910/


Can your NIC peer-into a GRE tunnel (?) to do CKO on the encapsulated
> traffic?
>


Again, no idea... No idea...   :-/

Listen, maybe this sounds too dumb from my part but, it is the first time
I'm talking about this stuff (like "NIC peer-into GRE" ?, or GRO / CKO...

GRE tunnels sounds too damn complex and problematic... I guess it is time
to try VXLAN (or NVP ?)...

If you guys say: VXLAN is a completely different beast (i.e. it does not
touch with ANY GRE tunnel), and it works smoothly (without GRO / CKO / MTU
/ lags / low speed troubles and issues), I'll move to it right now (is
VXLAN docs ready?).

NOTE: I don't want to hijack this thread because of other (internal
communication VS "Directional network performance issues with Neutron +
OpenvSwitch" thread subject) problems with my OpenStack environment,
please, let me know if this becomes a problem for you guys.



>  So, there is only 1 remain problem, when traffic pass trough L3 /
>> Namespace, it is still useless. Even the SSH connection into my
>> Instances, via its Floating IPs, is slow as hell, sometimes it just
>> stops responding for a few seconds, and becomes online again
>> "out-of-nothing"...
>>
>> I just detect a weird "behavior", when I run "apt-get update" from
>> instance-1, it is slow as I said plus, its ssh connection (where I'm
>> running apt-get update), stops responding right after I run "apt-get
>> update" AND, _all my others ssh connections also stops working too!_ For
>>
>> a few seconds... This means that when I run "apt-get update" from within
>> instance-1, the SSH session of instance-2 is affected too!! There is
>> something pretty bad going on at L3 / Namespace.
>>
>> BTW, do you think that a ~400MBit/sec intra-vm-communication (GRE
>> tunnel) on top of a 1Gbit ethernet is acceptable?! It is still less than
>> a half...
>>
>
> I would suggest checking for individual CPUs maxing-out during the 400
> Mbit/s transfers.


Okay, I'll.


>
>
> rick jones
>

Thiago
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.openstack.org/pipermail/openstack/attachments/20131025/29bbc323/attachment.html>